supercode-harness 0.4.2

//! Versioned, language-neutral service over persisted harness sessions.
//!
//! The service is transport-agnostic: [`HarnessSessionService::handle`] accepts
//! one JSON-RPC value and [`HarnessSessionService::poll`] produces subscription
//! notifications. The CLI exposes those primitives as NDJSON over stdio.

use std::collections::{BTreeMap, BTreeSet};
use std::path::{Path, PathBuf};
use std::time::Duration;

use serde::{Deserialize, Serialize};
use serde_json::{json, Value};

use crate::runtime::generated_session_id;
#[cfg(feature = "adapter-api")]
use crate::runtime::{HostedHarnessConnection, HostedHarnessRuntime};
use crate::sdk::{
    discover_session_page, load_session, load_session_with_fidelity, SdkCapabilities, SdkError,
    SdkErrorCode, SdkEvent, SdkOperation, SdkRequest, SdkRuntimeEvent, SdkService,
};
use crate::watch::{bound_session_view, message_json, normalized_session_json};
use crate::Fidelity;
#[cfg(feature = "adapter-api")]
use crate::SupercodeHttpRuntimeBackend;
use crate::{
    discover_live_runtime, harness_support_registry, AcpRuntimeBackend, ClaudeCodeRuntimeBackend,
    CodexRuntimeBackend, DiscoveryQuery, HarnessCatalog, HarnessId, ImplementationKind,
    LiveRuntimeEndpoint, LiveRuntimeSource, OpenCodeRuntimeBackend, PiRuntimeBackend, Role,
    RuntimeAttachRequest, RuntimeBackend, RuntimeConnection, RuntimeInput, RuntimeLaunch,
    RuntimeStartRequest, Session, SessionFollower, SessionFormat, SessionLocator, SessionSource,
};
use crate::{reduce, tokens};
#[cfg(feature = "adapter-api")]
use crate::{register_live_runtime, resolve_live_runtime, LiveRuntimeRegistration};

/// Protocol namespace implemented by this service.
pub const HARNESS_SERVICE_VERSION: &str = "harness.v1";
/// Notification method emitted for followed-session changes.
pub const SESSION_EVENT_METHOD: &str = "harness.v1.sessions.event";
/// Notification method emitted for live runtime events.
pub const RUNTIME_EVENT_METHOD: &str = "harness.v1.runtimes.event";

/// Stateful persisted-session service. Each instance owns its follow
/// subscriptions; discovery and loading remain read-only.
pub struct HarnessSessionService {
    catalog: HarnessCatalog,
    followers: BTreeMap<String, SessionFollower>,
    followed_sources: BTreeMap<String, FollowedSource>,
    next_subscription: u64,
    runtimes: BTreeMap<String, Box<dyn RuntimeConnection>>,
    terminal_launches: BTreeMap<String, StructuredLaunch>,
    runtime_sequences: BTreeMap<String, u64>,
    next_runtime: u64,
    reduction_store_root: Option<PathBuf>,
}

impl Default for HarnessSessionService {
    fn default() -> Self {
        Self::new()
    }
}

impl HarnessSessionService {
    /// Create an empty service instance.
    pub fn new() -> Self {
        Self {
            catalog: HarnessCatalog::new(),
            followers: BTreeMap::new(),
            followed_sources: BTreeMap::new(),
            next_subscription: 1,
            runtimes: BTreeMap::new(),
            terminal_launches: BTreeMap::new(),
            runtime_sequences: BTreeMap::new(),
            next_runtime: 1,
            reduction_store_root: None,
        }
    }

    /// Override the trusted, service-owned store used for durable reduction
    /// bundles. Embedders and tests use this to keep all writes inside an
    /// explicitly selected root; the CLI otherwise uses the normal
    /// `$SUPERCODE_HOME/sessions` location.
    pub fn with_reduction_store_root(mut self, root: impl Into<PathBuf>) -> Self {
        self.reduction_store_root = Some(root.into());
        self
    }

    /// Handle one JSON-RPC 2.0 request and return one JSON-RPC response.
    #[cfg(feature = "adapter-api")]
    pub fn handle(&mut self, request: Value) -> Value {
        let id = request.get("id").cloned().unwrap_or(Value::Null);
        if request.get("jsonrpc").and_then(Value::as_str) != Some("2.0") {
            return rpc_error(id, -32600, "expected a JSON-RPC 2.0 request");
        }
        let Some(method) = request.get("method").and_then(Value::as_str) else {
            return rpc_error(id, -32600, "request is missing `method`");
        };
        let params = request.get("params").cloned().unwrap_or_else(|| json!({}));
        match self.call(method, params) {
            Ok(result) => json!({"jsonrpc": "2.0", "id": id, "result": result}),
            Err(ServiceError::InvalidParams(message)) => rpc_error(id, -32602, &message),
            Err(ServiceError::MethodNotFound) => rpc_error(id, -32601, "method not found"),
            Err(ServiceError::UnsupportedAction(message)) => rpc_error(id, -32020, &message),
            Err(ServiceError::Operation(message)) => rpc_error(id, -32000, &message),
            Err(ServiceError::Sdk(error)) => sdk_rpc_error(id, &error),
        }
    }

    /// Handle either a persisted-session request or an asynchronous live
    /// runtime request.
    #[cfg(feature = "adapter-api")]
    pub async fn handle_async(&mut self, request: Value) -> Value {
        let method = request
            .get("method")
            .and_then(Value::as_str)
            .unwrap_or_default();
        if matches!(
            method,
            "harness.v1.harnesses.list" | "harness.v1.harnesses.probe"
        ) {
            let id = request.get("id").cloned().unwrap_or(Value::Null);
            if request.get("jsonrpc").and_then(Value::as_str) != Some("2.0") {
                return rpc_error(id, -32600, "expected a JSON-RPC 2.0 request");
            }
            let params = request.get("params").cloned().unwrap_or_else(|| json!({}));
            return match self.inventory_call(method, params).await {
                Ok(result) => json!({"jsonrpc": "2.0", "id": id, "result": result}),
                Err(ServiceError::InvalidParams(message)) => rpc_error(id, -32602, &message),
                Err(ServiceError::MethodNotFound) => rpc_error(id, -32601, "method not found"),
                Err(ServiceError::UnsupportedAction(message)) => rpc_error(id, -32020, &message),
                Err(ServiceError::Operation(message)) => rpc_error(id, -32000, &message),
                Err(ServiceError::Sdk(error)) => sdk_rpc_error(id, &error),
            };
        }
        if method == "harness.v1.sessions.message" {
            let id = request.get("id").cloned().unwrap_or(Value::Null);
            if request.get("jsonrpc").and_then(Value::as_str) != Some("2.0") {
                return rpc_error(id, -32600, "expected a JSON-RPC 2.0 request");
            }
            let params = request.get("params").cloned().unwrap_or_else(|| json!({}));
            return match self.message_call(params).await {
                Ok(result) => json!({"jsonrpc": "2.0", "id": id, "result": result}),
                Err(ServiceError::InvalidParams(message)) => rpc_error(id, -32602, &message),
                Err(ServiceError::MethodNotFound) => rpc_error(id, -32601, "method not found"),
                Err(ServiceError::UnsupportedAction(message)) => rpc_error(id, -32020, &message),
                Err(ServiceError::Operation(message)) => rpc_error(id, -32000, &message),
                Err(ServiceError::Sdk(error)) => sdk_rpc_error(id, &error),
            };
        }
        if let Some(operation) = SdkOperation::from_method(method) {
            let id = request.get("id").cloned().unwrap_or(Value::Null);
            if request.get("jsonrpc").and_then(Value::as_str) != Some("2.0") {
                return rpc_error(id, -32600, "expected a JSON-RPC 2.0 request");
            }
            let params = request.get("params").cloned().unwrap_or_else(|| json!({}));
            return match self.execute(SdkRequest { operation, params }).await {
                Ok(result) => json!({"jsonrpc": "2.0", "id": id, "result": result}),
                Err(error) => sdk_rpc_error(id, &error),
            };
        }
        if !method.starts_with("harness.v1.runtimes.") {
            return self.handle(request);
        }
        let id = request.get("id").cloned().unwrap_or(Value::Null);
        if request.get("jsonrpc").and_then(Value::as_str) != Some("2.0") {
            return rpc_error(id, -32600, "expected a JSON-RPC 2.0 request");
        }
        let params = request.get("params").cloned().unwrap_or_else(|| json!({}));
        match self.runtime_call(method, params).await {
            Ok(result) => json!({"jsonrpc": "2.0", "id": id, "result": result}),
            Err(ServiceError::InvalidParams(message)) => rpc_error(id, -32602, &message),
            Err(ServiceError::MethodNotFound) => rpc_error(id, -32601, "method not found"),
            Err(ServiceError::UnsupportedAction(message)) => rpc_error(id, -32020, &message),
            Err(ServiceError::Operation(message)) => rpc_error(id, -32000, &message),
            Err(ServiceError::Sdk(error)) => sdk_rpc_error(id, &error),
        }
    }

    /// Poll all active subscriptions once and return zero or more JSON-RPC
    /// notifications. Recoverable follower errors are delivered as events.
    #[cfg(feature = "adapter-api")]
    pub fn poll(&mut self) -> Vec<Value> {
        let mut notifications = Vec::new();
        for (subscription, follower) in &mut self.followers {
            match follower.poll() {
                Ok(Some(event)) => notifications.push(json!({
                    "jsonrpc": "2.0",
                    "method": SESSION_EVENT_METHOD,
                    "params": {
                        "subscription": subscription,
                        "event": event.to_json(),
                    }
                })),
                Ok(None) => {}
                Err(error) => notifications.push(json!({
                    "jsonrpc": "2.0",
                    "method": SESSION_EVENT_METHOD,
                    "params": {
                        "subscription": subscription,
                        "event": {
                            "type": "watch_error",
                            "recoverable": true,
                            "message": error.to_string(),
                        },
                    }
                })),
            }
        }
        notifications
    }

    /// Report each followed session's live-runtime lifecycle state on that
    /// session's own subscription, emitting only when the state changes.
    ///
    /// A growing transcript is not evidence that an agent is working, so the
    /// state comes from the live-runtime registry and nowhere else. A followed
    /// session with no registered Supercode runtime — a harness running outside
    /// Supercode — reports `persisted`, which says plainly that its activity is
    /// unknown rather than guessing at it. These events carry no sequence
    /// number and no transcript content; they never interleave with the
    /// content follower's sequenced stream.
    #[cfg(feature = "adapter-api")]
    pub async fn poll_session_runtime_states(&mut self) -> Vec<Value> {
        let registry = crate::LocalRuntimeRegistry::new();
        let authorization = crate::RuntimeAuthorization::observer();
        let mut notifications = Vec::new();
        for (subscription, source) in &mut self.followed_sources {
            let state = match registry
                .source_state(&source.harness, &source.session_id, &authorization)
                .await
            {
                Ok(Some(state)) => state,
                Ok(None) => crate::RuntimeRegistryState::Persisted,
                // A failed registry read is not evidence of a state change.
                Err(_) => continue,
            };
            if source.reported.as_deref() == Some(state.as_str()) {
                continue;
            }
            source.reported = Some(state.as_str().to_string());
            notifications.push(json!({
                "jsonrpc": "2.0",
                "method": SESSION_EVENT_METHOD,
                "params": {
                    "subscription": subscription,
                    "event": {"type": "runtime_state", "state": state.as_str()},
                },
            }));
        }
        notifications
    }

    /// Non-blockingly sample one event from every connected live runtime.
    #[cfg(feature = "adapter-api")]
    pub async fn poll_runtimes(&mut self) -> Vec<Value> {
        self.poll_sdk_events()
            .await
            .into_iter()
            .map(|(connection, runtime_event)| {
                json!({
                    "jsonrpc": "2.0",
                    "method": RUNTIME_EVENT_METHOD,
                    "params": {
                        "connection": connection,
                        "session_id": runtime_event.session_id,
                        "sequence": runtime_event.event.sequence,
                        "event": {
                            "kind": runtime_event.event.kind,
                            "payload": runtime_event.event.payload,
                        },
                    },
                })
            })
            .collect()
    }

    async fn poll_sdk_events(&mut self) -> Vec<(String, SdkRuntimeEvent)> {
        let mut events = Vec::new();
        let mut closed = Vec::new();
        for (connection, runtime) in &mut self.runtimes {
            let session_id = runtime.handle().runtime_id.clone();
            match tokio::time::timeout(Duration::from_millis(1), runtime.next_event()).await {
                Ok(Ok(Some(event))) => {
                    let terminal = event.kind == "transport_closed";
                    let next_sequence = self
                        .runtime_sequences
                        .entry(session_id.clone())
                        .or_insert(0);
                    let sequence = event.sequence.unwrap_or_else(|| {
                        *next_sequence = next_sequence.saturating_add(1);
                        *next_sequence
                    });
                    *next_sequence = (*next_sequence).max(sequence);
                    events.push((
                        connection.clone(),
                        SdkRuntimeEvent {
                            session_id: session_id.clone(),
                            event: SdkEvent {
                                sequence,
                                kind: event.kind,
                                payload: event.payload,
                            },
                        },
                    ));
                    if terminal {
                        closed.push(connection.clone());
                    }
                }
                Ok(Ok(None)) => {
                    let sequence = self
                        .runtime_sequences
                        .entry(session_id.clone())
                        .or_insert(0);
                    *sequence = sequence.saturating_add(1);
                    events.push((
                        connection.clone(),
                        SdkRuntimeEvent {
                            session_id,
                            event: SdkEvent {
                                sequence: *sequence,
                                kind: "transport_closed".into(),
                                payload: json!({"message": "Harness runtime transport closed."}),
                            },
                        },
                    ));
                    closed.push(connection.clone());
                }
                Err(_) => {}
                Ok(Err(error)) => {
                    let sequence = self
                        .runtime_sequences
                        .entry(session_id.clone())
                        .or_insert(0);
                    *sequence = sequence.saturating_add(1);
                    events.push((
                        connection.clone(),
                        SdkRuntimeEvent {
                            session_id,
                            event: SdkEvent {
                                sequence: *sequence,
                                kind: "transport_error".into(),
                                payload: json!({"message": error.to_string(), "terminal": true}),
                            },
                        },
                    ));
                    closed.push(connection.clone());
                }
            }
        }
        for connection in closed {
            if let Some(runtime) = self.runtimes.remove(&connection) {
                self.runtime_sequences.remove(&runtime.handle().runtime_id);
            }
            self.terminal_launches.remove(&connection);
        }
        events
    }

    fn call(&mut self, method: &str, params: Value) -> std::result::Result<Value, ServiceError> {
        match method {
            "harness.v1.capabilities" => Ok(json!({
                "version": HARNESS_SERVICE_VERSION,
                "sdk": self.capabilities(),
                "methods": [
                    "harness.v1.support.report",
                    "harness.v1.harnesses.list",
                    "harness.v1.harnesses.probe",
                    "harness.v1.sessions.discover",
                    "harness.v1.sessions.load",
                    "harness.v1.sessions.follow",
                    "harness.v1.sessions.unfollow",
                    "harness.v1.sessions.message",
                    "harness.v1.sessions.import",
                    "harness.v1.sessions.export",
                    "harness.v1.sessions.translate",
                    "harness.v1.sessions.reduce",
                    "harness.v1.sessions.branch",
                    "harness.v1.sessions.handoff",
                    "harness.v1.sessions.resume_instructions",
                    "harness.v1.runtimes.capabilities",
                    "harness.v1.runtimes.start",
                    "harness.v1.runtimes.resume",
                    "harness.v1.runtimes.attach_existing",
                    "harness.v1.runtimes.attach",
                    "harness.v1.runtimes.send_input",
                    "harness.v1.runtimes.interrupt",
                    "harness.v1.runtimes.steer",
                    "harness.v1.runtimes.respond",
                    "harness.v1.runtimes.terminal_instructions",
                    "harness.v1.runtimes.close",
                ],
                "notifications": [SESSION_EVENT_METHOD, RUNTIME_EVENT_METHOD],
                "harnesses": harness_support_registry()
                    .harnesses
                    .into_iter()
                    .map(|harness| harness.id)
                    .collect::<Vec<_>>(),
            })),
            "harness.v1.support.report" => serde_json::to_value(harness_support_registry())
                .map_err(|error| ServiceError::Operation(error.to_string())),
            "harness.v1.sessions.discover" => {
                let query = decode::<DiscoveryQuery>(params)?;
                let page = discover_session_page(&query).map_err(operation)?;
                // Claude Code is the one harness that publishes its RUNNING
                // sessions. The registry is read once per discovery and joined
                // by session id; every record in it has already survived a
                // `kill(pid, 0)` liveness check inside `read_registry`.
                let peers = if page
                    .sessions
                    .iter()
                    .any(|session| session.locator.harness.as_str() == HarnessId::CLAUDE_CODE)
                {
                    crate::claude_peer::read_registry(&crate::claude_peer::registry_dir(
                        &query.homes,
                    ))
                } else {
                    Vec::new()
                };
                let sessions = page
                    .sessions
                    .into_iter()
                    .map(|session| {
                        let mut value = serde_json::to_value(&session)
                            .map_err(|error| ServiceError::Operation(error.to_string()))?;
                        if let Some(workspace) = &session.cwd {
                            let source = LiveRuntimeSource {
                                harness: session.locator.harness.as_str().to_string(),
                                session_id: session.locator.session_id.clone(),
                                workspace: workspace.clone(),
                            };
                            if let Some(endpoint) = discover_live_runtime(&source)
                                .map_err(|error| ServiceError::Operation(error.to_string()))?
                            {
                                value["live_endpoint"] = json!(endpoint.as_str());
                            }
                        }
                        if let Some(peer) = peers.iter().find(|peer| {
                            session.locator.harness.as_str() == HarnessId::CLAUDE_CODE
                                && peer.session_id == session.locator.session_id
                        }) {
                            // A Supercode-hosted runtime is the richer
                            // attachment, so it keeps the endpoint slot; the
                            // peer endpoint fills it only when nothing else did.
                            if value.get("live_endpoint").is_none() {
                                value["live_endpoint"] = json!(peer.endpoint().as_str());
                            }
                            if let Some(status) = peer.status {
                                value["live_status"] = json!(status.as_str());
                            }
                        }
                        Ok(value)
                    })
                    .collect::<std::result::Result<Vec<_>, ServiceError>>()?;
                Ok(json!({"sessions": sessions, "next_cursor": page.next_cursor}))
            }
            "harness.v1.sessions.load" => {
                let params = decode::<LoadSessionParams>(params)?;
                if let Some(options) = &params.options {
                    options.validate()?;
                    return load_session(&params.read.locator)
                        .map(|session| projected_session_result(&session, options))
                        .map_err(operation);
                }
                let mut session = if params.read.display_history() {
                    self.catalog
                        .load_display_view(
                            &params.read.locator,
                            params.read.read_fidelity(),
                            params.read.tail_messages().unwrap_or(500),
                        )
                        .map_err(crate::Error::from)
                } else if params.read.include_subagents() {
                    load_session_with_fidelity(&params.read.locator, params.read.read_fidelity())
                } else {
                    self.catalog
                        .load_parent_with_fidelity(
                            &params.read.locator,
                            params.read.read_fidelity(),
                        )
                        .map_err(crate::Error::from)
                }
                .map_err(operation)?;
                params.read.bound_session(&mut session);
                Ok(json!({"session": normalized_session_json(&session)}))
            }
            "harness.v1.sessions.follow" => {
                let params = decode::<LocatorParams>(params)?;
                let mut follower = self
                    .catalog
                    .follow_read_view(
                        &params.locator,
                        params.read_fidelity(),
                        params.include_subagents(),
                        params.tail_messages(),
                        params.max_message_chars(),
                        params.display_history(),
                    )
                    .map_err(operation)?;
                let initial = follower
                    .poll()
                    .map_err(operation)?
                    .map(|event| event.to_json());
                let subscription = format!("sub-{}", self.next_subscription);
                self.next_subscription += 1;
                self.followers.insert(subscription.clone(), follower);
                self.followed_sources.insert(
                    subscription.clone(),
                    FollowedSource {
                        harness: params.locator.harness.as_str().to_string(),
                        session_id: params.locator.session_id.clone(),
                        reported: None,
                    },
                );
                Ok(json!({"subscription": subscription, "initial": initial}))
            }
            "harness.v1.sessions.unfollow" => {
                let params = decode::<UnfollowParams>(params)?;
                self.followed_sources.remove(&params.subscription);
                Ok(json!({
                    "removed": self.followers.remove(&params.subscription).is_some()
                }))
            }
            "harness.v1.sessions.import" => {
                let params = decode::<ImportSessionParams>(params)?;
                let session = Session::load_str(&params.content, params.source_harness.into())
                    .map_err(operation)?;
                Ok(json!({"session": normalized_session_json(&session)}))
            }
            "harness.v1.sessions.export" | "harness.v1.sessions.translate" => {
                let params = decode::<ExportSessionParams>(params)?;
                let session = load_session(&params.locator).map_err(operation)?;
                let artifact = session_artifact(&params.locator, &session, params.target_harness)?;
                Ok(json!({"artifact": artifact}))
            }
            "harness.v1.sessions.reduce" => {
                let params = decode::<ReduceSessionParams>(params)?;
                self.reduce_session(params)
            }
            "harness.v1.sessions.branch" => {
                let params = decode::<BranchSessionParams>(params)?;
                let session = load_session(&params.locator).map_err(operation)?;
                let storage = params.locator.storage.path().display().to_string();
                let bootstrap_prompt = format!(
                    "Continue as a new branch from {} session {}. The frozen parent transcript is at {}. Read or load that parent for context, summarize the relevant state, then continue independently without mutating the parent session.",
                    params.locator.harness.as_str(), params.locator.session_id, storage
                );
                let artifact = params
                    .target_harness
                    .map(|target| session_artifact(&params.locator, &session, target))
                    .transpose()?;
                Ok(json!({
                    "parent": params.locator,
                    "session": normalized_session_json(&session),
                    "bootstrap_prompt": bootstrap_prompt,
                    "artifact": artifact,
                }))
            }
            "harness.v1.sessions.handoff" => {
                let params = decode::<HandoffSessionParams>(params)?;
                let session = load_session(&params.locator).map_err(operation)?;
                let cwd = params
                    .cwd
                    .or_else(|| session.meta.cwd.clone())
                    .unwrap_or_else(|| PathBuf::from("."));
                let artifact =
                    handoff_artifact(&params.locator, &session, params.target_harness, &cwd)?;
                let target_session_id = artifact.session_id.as_deref().ok_or_else(|| {
                    ServiceError::Operation(
                        "handoff artifact omitted target session identity".into(),
                    )
                })?;
                let instructions =
                    handoff_instructions(params.target_harness, target_session_id, &cwd);
                Ok(json!({
                    "artifact": artifact,
                    "launch": instructions.launch,
                    "materialize": instructions.materialize,
                    "requires_materialization": instructions.requires_materialization,
                    "note": instructions.note,
                }))
            }
            "harness.v1.sessions.resume_instructions" => {
                let params = decode::<ResumeInstructionsParams>(params)?;
                let session = load_session(&params.locator).map_err(operation)?;
                let cwd = params
                    .cwd
                    .or(session.meta.cwd)
                    .unwrap_or_else(|| PathBuf::from("."));
                let launch = resume_launch(
                    params.locator.harness.as_str(),
                    &params.locator.session_id,
                    &cwd,
                    params.policy,
                )?;
                Ok(json!({"launch": launch}))
            }
            _ => Err(ServiceError::MethodNotFound),
        }
    }

    fn reduce_session(
        &self,
        params: ReduceSessionParams,
    ) -> std::result::Result<Value, ServiceError> {
        let session = load_session(&params.locator).map_err(operation)?;
        if session.messages.is_empty() {
            return Err(ServiceError::InvalidParams(
                "cannot reduce an empty session".into(),
            ));
        }
        let keep_last = params.keep_last.clamp(1, 128);
        let policy = reduce::ReductionPolicy {
            clear_turns_older_than: Some(keep_last),
            ..Default::default()
        };
        let (view, log) =
            reduce::project_messages(&session.messages, &policy, &reduce::ReductionLog::default());
        if log.reductions.is_empty() {
            return Err(ServiceError::UnsupportedAction(format!(
                "session `{}` is already too small for a meaningful reversible reduction",
                params.locator.session_id
            )));
        }
        let source_tokens = tokens::estimate_view_tokens(&session.messages);
        let reduced_tokens = tokens::estimate_view_tokens(&view);
        if reduced_tokens >= source_tokens {
            return Err(ServiceError::UnsupportedAction(format!(
                "session `{}` has no token-reducing reversible projection",
                params.locator.session_id
            )));
        }

        let store_root = self
            .reduction_store_root
            .clone()
            .unwrap_or_else(default_reduction_store_root);
        let store = crate::SessionStore::open(&store_root).map_err(operation)?;
        let rescue_id = format!("rescue-{}", generated_session_id());
        let imported = session
            .imported_message_count
            .unwrap_or(session.messages.len())
            .min(session.messages.len());
        let sidecar_jsonl = session.to_native_jsonl_v2(&session.messages[imported..]);
        let view_jsonl = messages_jsonl(&view)?;
        let title = format!(
            "Reduced {} continuation from {}",
            params.target_harness.id(),
            params.locator.session_id
        );

        // Durability order is intentional: the full source of truth lands
        // before either object that can refer to it. A crash may leave an
        // unused sidecar, but can never leave a reduced view whose originals
        // were not durably written first.
        store
            .save_sidecar(&rescue_id, &sidecar_jsonl)
            .map_err(operation)?;
        store
            .save_reduction_log(&rescue_id, &log)
            .map_err(operation)?;
        store
            .save(&rescue_id, &title, &view_jsonl)
            .map_err(operation)?;

        let source_bytes = serde_json::to_vec(&session.messages)
            .map_err(|error| ServiceError::Operation(error.to_string()))?
            .len() as u64;
        let reduced_bytes = serde_json::to_vec(&view)
            .map_err(|error| ServiceError::Operation(error.to_string()))?
            .len() as u64;
        store
            .set_reduction_stats(
                &rescue_id,
                &title,
                source_bytes,
                reduced_bytes,
                log.reductions.len() as u32,
            )
            .map_err(operation)?;

        // The receipt is issued only after a real disk reload. This proves
        // the exact files another process will consume, not the convenient
        // in-memory values that produced them.
        let reloaded_sidecar = store
            .load_sidecar(&rescue_id)
            .map_err(operation)?
            .ok_or_else(|| ServiceError::Operation("reduction sidecar disappeared".into()))?;
        let reloaded_sidecar = Session::from_sidecar_str(&reloaded_sidecar).map_err(operation)?;
        let reloaded_log = store
            .load_reduction_log(&rescue_id)
            .map_err(operation)?
            .ok_or_else(|| ServiceError::Operation("reduction log disappeared".into()))?;
        let reloaded_view = parse_messages_jsonl(&store.load(&rescue_id).map_err(operation)?)?;
        reduce::verify_log(&reloaded_log, &reloaded_sidecar).map_err(operation)?;
        // `sc.reduction` is deliberately in-memory-only metadata: it must
        // never leak onto a provider-facing transcript. Reapplying the
        // durable log to the durable sidecar restores those ids. Comparing
        // its wire form with the transcript reloaded above proves that the
        // persisted view is exactly the deterministic projection before we
        // use the restamped form for inversion.
        let (restamped_view, restamped_log) =
            reduce::project_messages(&reloaded_sidecar.messages, &policy, &reloaded_log);
        if messages_jsonl(&restamped_view)? != messages_jsonl(&reloaded_view)? {
            return Err(ServiceError::Operation(
                "persisted reduction view does not match its durable log and sidecar".into(),
            ));
        }
        if restamped_log != reloaded_log {
            return Err(ServiceError::Operation(
                "reapplying the durable reduction log changed its identity".into(),
            ));
        }
        let inverted =
            reduce::invert(&restamped_view, &reloaded_log, &reloaded_sidecar).map_err(operation)?;
        if inverted != session.messages {
            return Err(ServiceError::Operation(
                "reduction inversion did not restore the source messages byte-exactly".into(),
            ));
        }

        let ratio = source_tokens as f64 / reduced_tokens.max(1) as f64;
        let sidecar_path = store.sidecar_path(&rescue_id);
        let reduction_log_path = store.reduction_log_path(&rescue_id).map_err(operation)?;
        let bootstrap_prompt = reduced_bootstrap_prompt(
            &params.locator,
            params.target_harness,
            &view_jsonl,
            &sidecar_path,
            &reduction_log_path,
        );
        let mut reduced_session = session.clone();
        reduced_session.meta.session_id = Some(rescue_id.clone());
        reduced_session.messages = view;

        Ok(json!({
            "session": normalized_session_json(&reduced_session),
            "bootstrap_prompt": bootstrap_prompt,
            "receipt": {
                "id": rescue_id,
                "sidecar_id": rescue_id,
                "source_harness": params.locator.harness,
                "target_harness": params.target_harness.id(),
                "source_tokens": source_tokens,
                "reduced_tokens": reduced_tokens,
                "ratio": ratio,
                "source_bytes": source_bytes,
                "reduced_bytes": reduced_bytes,
                "reductions": reloaded_log.reductions.len(),
                "sidecar_path": sidecar_path,
                "reduction_log_path": reduction_log_path,
                "verified": true,
                "reversible": true,
            }
        }))
    }

    async fn runtime_call(
        &mut self,
        method: &str,
        params: Value,
    ) -> std::result::Result<Value, ServiceError> {
        match method {
            "harness.v1.runtimes.capabilities" => {
                let params = decode::<RuntimeBackendParams>(params)?;
                let backend = runtime_backend(&params)?;
                Ok(json!({
                    "harness": backend.harness(),
                    "capabilities": backend.capabilities(),
                }))
            }
            "harness.v1.runtimes.start" => {
                let params = decode::<RuntimeStartParams>(params)?;
                let backend = runtime_backend(&params.backend)?;
                let capabilities = backend.capabilities();
                let workspace = params.cwd.clone();
                let runtime = backend
                    .start(RuntimeStartRequest {
                        cwd: params.cwd,
                        launch: runtime_launch(&params.backend),
                    })
                    .await
                    .map_err(operation)?;
                self.insert_hosted_runtime(runtime, capabilities, workspace)
                    .await
            }
            "harness.v1.runtimes.resume" | "harness.v1.runtimes.attach" => {
                let params = decode::<RuntimeAttachParams>(params)?;
                let backend = runtime_backend(&params.backend)?;
                let capabilities = backend.capabilities();
                let workspace = params.cwd.clone().unwrap_or_else(|| {
                    std::env::current_dir().unwrap_or_else(|_| PathBuf::from("."))
                });
                let runtime = backend
                    .attach(RuntimeAttachRequest {
                        runtime_id: params.runtime_id,
                        cwd: params.cwd,
                        launch: runtime_launch(&params.backend),
                    })
                    .await
                    .map_err(operation)?;
                self.insert_hosted_runtime(runtime, capabilities, workspace)
                    .await
            }
            "harness.v1.runtimes.attach_existing" => {
                let params = decode::<RuntimeAttachParams>(params)?;
                let backend: Box<dyn RuntimeBackend> = match params
                    .backend
                    .base_url
                    .as_deref()
                    .and_then(|value| LiveRuntimeEndpoint::parse(value).ok())
                {
                    Some(endpoint) => {
                        #[cfg(not(feature = "adapter-api"))]
                        {
                            let _ = endpoint;
                            return Err(ServiceError::UnsupportedAction(
                                "live HTTP attachment adapter is not compiled".into(),
                            ));
                        }
                        #[cfg(feature = "adapter-api")]
                        {
                            let workspace = params.cwd.clone().ok_or_else(|| {
                                ServiceError::InvalidParams(
                                    "Supercode live attach requires the project cwd".into(),
                                )
                            })?;
                            let source = LiveRuntimeSource {
                                harness: params.backend.harness.as_str().to_string(),
                                session_id: params.runtime_id.clone(),
                                workspace,
                            };
                            let receipt = resolve_live_runtime(&endpoint, &source)
                                .map_err(|error| ServiceError::Operation(error.to_string()))?;
                            Box::new(SupercodeHttpRuntimeBackend::new(receipt))
                        }
                    }
                    None => runtime_backend(&params.backend)?,
                };
                if !backend.capabilities().attach_existing_process {
                    return Err(ServiceError::Operation(format!(
                        "{} cannot attach to an already-running process; use runtimes.resume for a persisted session",
                        backend.harness().as_str()
                    )));
                }
                let runtime = backend
                    .attach_existing(RuntimeAttachRequest {
                        runtime_id: params.runtime_id,
                        cwd: params.cwd,
                        launch: runtime_launch(&params.backend),
                    })
                    .await
                    .map_err(operation)?;
                self.insert_runtime(runtime)
            }
            "harness.v1.runtimes.send_input" => {
                let params = decode::<RuntimeInputParams>(params)?;
                let runtime = self.runtime_mut(&params.connection)?;
                let turn_id = runtime
                    .send_input(RuntimeInput { text: params.text })
                    .await
                    .map_err(operation)?;
                Ok(json!({"turn_id": turn_id}))
            }
            "harness.v1.runtimes.interrupt" => {
                let params = decode::<RuntimeConnectionParams>(params)?;
                self.runtime_mut(&params.connection)?
                    .interrupt()
                    .await
                    .map_err(operation)?;
                Ok(json!({}))
            }
            "harness.v1.runtimes.steer" => Err(ServiceError::UnsupportedAction(
                "steer is not supported by this harness-native runtime adapter".into(),
            )),
            "harness.v1.runtimes.respond" => {
                let params = decode::<RuntimeRespondParams>(params)?;
                self.runtime_mut(&params.connection)?
                    .respond(params.request_id, params.response)
                    .await
                    .map_err(operation)?;
                Ok(json!({}))
            }
            "harness.v1.runtimes.terminal_instructions" => {
                let params = decode::<RuntimeConnectionParams>(params)?;
                let launch = self
                    .terminal_launches
                    .get(&params.connection)
                    .ok_or_else(|| {
                        ServiceError::Operation(
                            "this runtime is not hosted for terminal attachment".into(),
                        )
                    })?;
                Ok(json!({"launch":launch}))
            }
            "harness.v1.runtimes.close" => {
                let params = decode::<RuntimeConnectionParams>(params)?;
                let Some(mut runtime) = self.runtimes.remove(&params.connection) else {
                    return Err(ServiceError::InvalidParams(format!(
                        "unknown runtime connection `{}`",
                        params.connection
                    )));
                };
                self.terminal_launches.remove(&params.connection);
                self.runtime_sequences.remove(&runtime.handle().runtime_id);
                runtime.close().await.map_err(operation)?;
                Ok(json!({"closed": true}))
            }
            _ => Err(ServiceError::MethodNotFound),
        }
    }

    /// Deliver one message into a session that is running right now.
    #[cfg(feature = "adapter-api")]
    async fn message_call(&self, params: Value) -> std::result::Result<Value, ServiceError> {
        let params = decode::<MessageSessionParams>(params)?;
        Ok(message_live_session(&params, &crate::claude_peer::ProcessCourierRunner).await)
    }

    fn insert_runtime(
        &mut self,
        runtime: Box<dyn RuntimeConnection>,
    ) -> std::result::Result<Value, ServiceError> {
        let connection = format!("runtime-{}", self.next_runtime);
        self.next_runtime += 1;
        let handle = runtime.handle().clone();
        self.runtime_sequences
            .entry(handle.runtime_id.clone())
            .or_insert(0);
        self.runtimes.insert(connection.clone(), runtime);
        Ok(json!({"connection": connection, "handle": handle}))
    }

    #[cfg(feature = "adapter-api")]
    async fn insert_hosted_runtime(
        &mut self,
        runtime: Box<dyn RuntimeConnection>,
        capabilities: crate::RuntimeCapabilities,
        workspace: PathBuf,
    ) -> std::result::Result<Value, ServiceError> {
        let (host, connection) = HostedHarnessRuntime::spawn(runtime, capabilities);
        let token: std::sync::Arc<str> = crate::server::generate_token().into();
        let server = crate::server::run_frontend_http(
            host.clone(),
            host.frontend_sender(),
            "127.0.0.1:0",
            token.clone(),
        )
        .await
        .map_err(|error| ServiceError::Operation(error.to_string()))?;
        let source = LiveRuntimeSource {
            harness: connection.handle().harness.as_str().to_string(),
            session_id: connection.handle().runtime_id.clone(),
            workspace: workspace.clone(),
        };
        let registration = register_live_runtime(
            connection.handle().runtime_id.clone(),
            source.clone(),
            format!("http://{}", server.address()),
            token.to_string(),
        )
        .map_err(|error| ServiceError::Operation(error.to_string()))?;
        let endpoint = registration.endpoint().to_string();
        let launch = StructuredLaunch {
            cwd: workspace,
            // Pin attachment to the executable hosting this runtime. A bare
            // `supercode` could resolve to an older global install whose CLI
            // does not understand the receipt it is being asked to open.
            program: std::env::current_exe()
                .ok()
                .map(|path| path.to_string_lossy().into_owned())
                .unwrap_or_else(|| "supercode".into()),
            arguments: vec![
                "harness".into(),
                "attach".into(),
                "--endpoint".into(),
                endpoint,
                "--harness".into(),
                source.harness,
                "--session".into(),
                source.session_id,
            ],
            env: BTreeMap::new(),
        };
        let lease = HostedRuntimeLease {
            connection,
            _host: host,
            _registration: registration,
            _server: server,
        };
        let opened = self.insert_runtime(Box::new(lease))?;
        let connection_id = opened["connection"]
            .as_str()
            .expect("insert_runtime returns a connection id")
            .to_string();
        self.terminal_launches.insert(connection_id, launch);
        Ok(opened)
    }

    #[cfg(not(feature = "adapter-api"))]
    async fn insert_hosted_runtime(
        &mut self,
        runtime: Box<dyn RuntimeConnection>,
        _capabilities: crate::RuntimeCapabilities,
        _workspace: PathBuf,
    ) -> std::result::Result<Value, ServiceError> {
        self.insert_runtime(runtime)
    }

    fn runtime_mut(
        &mut self,
        connection: &str,
    ) -> std::result::Result<&mut Box<dyn RuntimeConnection>, ServiceError> {
        self.runtimes.get_mut(connection).ok_or_else(|| {
            ServiceError::InvalidParams(format!("unknown runtime connection `{connection}`"))
        })
    }

    async fn inventory_call(
        &self,
        method: &str,
        params: Value,
    ) -> std::result::Result<Value, ServiceError> {
        let mut params = decode::<HarnessInventoryParams>(params)?;
        if method == "harness.v1.harnesses.probe" {
            let harness = params.harness.take().ok_or_else(|| {
                ServiceError::InvalidParams("harnesses.probe requires `harness`".into())
            })?;
            params.harnesses = vec![harness];
        }
        let selected = params
            .harnesses
            .iter()
            .map(HarnessId::as_str)
            .collect::<std::collections::BTreeSet<_>>();
        let supported = harness_support_registry()
            .harnesses
            .into_iter()
            .filter(|descriptor| selected.is_empty() || selected.contains(descriptor.id.as_str()))
            .collect::<Vec<_>>();
        if !params.harnesses.is_empty() && supported.len() != selected.len() {
            let known = supported
                .iter()
                .map(|harness| harness.id.as_str())
                .collect::<std::collections::BTreeSet<_>>();
            let missing = params
                .harnesses
                .iter()
                .filter(|id| !known.contains(id.as_str()))
                .map(HarnessId::as_str)
                .collect::<Vec<_>>();
            return Err(ServiceError::InvalidParams(format!(
                "unknown harness(es): {}",
                missing.join(", ")
            )));
        }
        let global_counts = params
            .include_sessions
            .then(|| self.session_counts(None, &params.harnesses));
        let workspace_counts = params.include_sessions.then(|| {
            params
                .workspace
                .as_deref()
                .map(|workspace| self.session_counts(Some(workspace), &params.harnesses))
        });
        let probes = supported.into_iter().map(|descriptor| {
            let global = global_counts
                .as_ref()
                .map(|counts| counts.get(descriptor.id.as_str()).copied().unwrap_or(0));
            let workspace = workspace_counts
                .as_ref()
                .and_then(Option::as_ref)
                .map(|counts| counts.get(descriptor.id.as_str()).copied().unwrap_or(0));
            self.probe_harness(descriptor, &params, global, workspace)
        });
        let harnesses = futures::future::join_all(probes).await;
        serde_json::to_value(HarnessInventoryReport {
            probe: params.probe,
            workspace: params.workspace,
            harnesses,
        })
        .map_err(|error| ServiceError::Operation(error.to_string()))
    }

    async fn probe_harness(
        &self,
        descriptor: crate::HarnessSupportDescriptor,
        params: &HarnessInventoryParams,
        global: Option<usize>,
        workspace: Option<usize>,
    ) -> LocalHarness {
        let launch = descriptor.runtime.default_launch.as_ref();
        let executable = launch.and_then(|launch| find_executable(&launch.program));
        let installed = executable.is_some();
        let version = if params.skip_versions {
            None
        } else {
            match executable.as_deref() {
                Some(path) => executable_version(path).await,
                None => None,
            }
        };
        let configured = auth_evidence(descriptor.id.as_str());
        let mut auth = if configured {
            HarnessAuthState::Configured
        } else {
            HarnessAuthState::Unknown
        };
        let mut runtime = if installed {
            HarnessRuntimeState::Degraded
        } else {
            HarnessRuntimeState::Unavailable
        };
        let mut reason = (!installed).then(|| {
            format!(
                "{} is supported but `{}` was not found on PATH",
                descriptor.display_name,
                launch
                    .map(|launch| launch.program.as_str())
                    .unwrap_or("executable")
            )
        });
        let mut repair = (!installed).then(|| {
            format!(
                "Install {} and ensure `{}` is on PATH.",
                descriptor.display_name,
                launch
                    .map(|launch| launch.program.as_str())
                    .unwrap_or("its executable")
            )
        });

        if installed && params.probe == HarnessProbeLevel::Handshake {
            let backend_params = RuntimeBackendParams {
                harness: descriptor.id.clone(),
                protocol: None,
                launch: None,
                base_url: None,
                policy: RuntimePolicy::Default,
            };
            match runtime_backend(&backend_params) {
                Ok(backend) => {
                    let cwd = params
                        .workspace
                        .clone()
                        .or_else(|| std::env::current_dir().ok())
                        .unwrap_or_else(|| PathBuf::from("."));
                    let isolated = descriptor
                        .runtime
                        .default_launch
                        .clone()
                        .and_then(|launch| {
                            IsolatedProbeHome::new(descriptor.id.as_str(), launch).ok()
                        });
                    let Some(isolated) = isolated else {
                        reason = Some(
                            "No-prompt runtime handshake could not create its isolated harness home."
                                .into(),
                        );
                        repair = Some(
                            "Check temporary-directory permissions, then run the handshake probe again."
                                .into(),
                        );
                        return LocalHarness {
                            id: descriptor.id,
                            display_name: descriptor.display_name,
                            supported: true,
                            installed,
                            executable: executable.map(|path| path.to_string_lossy().into_owned()),
                            version,
                            auth,
                            runtime,
                            protocol: descriptor.runtime.protocol,
                            capabilities: descriptor.runtime.capabilities.clone(),
                            effective_capabilities: descriptor.runtime.capabilities,
                            sessions: HarnessSessionCounts { global, workspace },
                            reason,
                            repair,
                        };
                    };
                    match tokio::time::timeout(
                        Duration::from_secs(30),
                        backend.start(RuntimeStartRequest {
                            cwd,
                            launch: Some(isolated.launch.clone()),
                        }),
                    )
                    .await
                    {
                        Ok(Ok(mut connection)) => {
                            match stabilize_handshake(connection.as_mut()).await {
                                Ok(()) => {
                                    auth = HarnessAuthState::Ready;
                                    runtime = HarnessRuntimeState::Ready;
                                    reason = Some(
                                        "No-prompt runtime handshake remained healthy through the startup stabilization window; no model request was sent."
                                            .into(),
                                    );
                                    repair = None;
                                }
                                Err(message) => {
                                    auth = if looks_like_auth_error(&message) {
                                        HarnessAuthState::Required
                                    } else if configured {
                                        HarnessAuthState::Configured
                                    } else {
                                        HarnessAuthState::Unknown
                                    };
                                    reason = Some(format!(
                                        "No-prompt runtime handshake became unhealthy during startup: {message}"
                                    ));
                                    repair = Some(if auth == HarnessAuthState::Required {
                                        format!(
                                            "Run `{}` interactively once and complete sign-in, then probe again.",
                                            launch.map(|launch| launch.program.as_str()).unwrap_or("the harness")
                                        )
                                    } else {
                                        "Run the harness directly to inspect its startup failure, then probe again."
                                            .into()
                                    });
                                }
                            }
                            let _ =
                                tokio::time::timeout(Duration::from_secs(3), connection.close())
                                    .await;
                        }
                        Ok(Err(error)) => {
                            let message = truncate_text(&error.to_string(), 500);
                            auth = if looks_like_auth_error(&message) {
                                HarnessAuthState::Required
                            } else if configured {
                                HarnessAuthState::Configured
                            } else {
                                HarnessAuthState::Unknown
                            };
                            reason = Some(format!("No-prompt runtime handshake failed: {message}"));
                            repair = Some(if auth == HarnessAuthState::Required {
                                format!(
                                    "Run `{}` interactively once and complete sign-in, then probe again.",
                                    launch.map(|launch| launch.program.as_str()).unwrap_or("the harness")
                                )
                            } else {
                                "Check the harness installation and run the handshake probe again."
                                    .into()
                            });
                        }
                        Err(_) => {
                            reason = Some(
                                "No-prompt runtime handshake timed out after 30 seconds.".into(),
                            );
                            repair = Some("Run the harness directly to check startup or authentication, then probe again.".into());
                        }
                    }
                    // Keep the isolated home alive through process teardown.
                    // Otherwise the compiler may release the last meaningful
                    // use after cloning `launch`, and a still-starting CLI can
                    // recreate its state directory after Drop removed it.
                    // Some Node-based launchers finish a short asynchronous
                    // installation-id write just after their parent process
                    // is reaped. Remove once immediately, allow that bounded
                    // writer to settle, then perform the authoritative pass.
                    let _ = isolated.cleanup();
                    tokio::time::sleep(Duration::from_millis(250)).await;
                    if let Err(error) = isolated.cleanup() {
                        auth = if configured {
                            HarnessAuthState::Configured
                        } else {
                            HarnessAuthState::Unknown
                        };
                        runtime = HarnessRuntimeState::Degraded;
                        reason = Some(format!(
                            "No-prompt runtime handshake could not remove its isolated harness home: {error}"
                        ));
                        repair = Some(
                            "Check temporary-directory permissions, remove the reported disposable probe home, then run the handshake again."
                                .into(),
                        );
                    }
                }
                Err(error) => {
                    reason = Some(error_message(error));
                }
            }
        } else if installed && configured {
            reason = Some("Executable and local authentication evidence found; use a handshake probe to verify readiness.".into());
        } else if installed {
            reason = Some("Executable found; authentication readiness is unknown until a no-prompt handshake succeeds.".into());
            repair =
                Some(format!(
                "Run `{}` interactively once if sign-in is required, or use `--probe handshake`.",
                launch.map(|launch| launch.program.as_str()).unwrap_or("the harness")
            ));
        }

        let effective_capabilities = if installed {
            descriptor.runtime.capabilities.clone()
        } else {
            unavailable_capabilities()
        };
        LocalHarness {
            id: descriptor.id,
            display_name: descriptor.display_name,
            supported: true,
            installed,
            executable: executable.map(|path| path.to_string_lossy().into_owned()),
            version,
            auth,
            runtime,
            protocol: descriptor.runtime.protocol,
            capabilities: descriptor.runtime.capabilities,
            effective_capabilities,
            sessions: HarnessSessionCounts { global, workspace },
            reason,
            repair,
        }
    }

    fn session_counts(
        &self,
        workspace: Option<&Path>,
        harnesses: &[HarnessId],
    ) -> BTreeMap<String, usize> {
        let mut counts = BTreeMap::new();
        for session in self
            .catalog
            .discover(&DiscoveryQuery {
                workspace: workspace.map(Path::to_path_buf),
                harnesses: harnesses.to_vec(),
                ..DiscoveryQuery::default()
            })
            .unwrap_or_default()
        {
            *counts
                .entry(session.locator.harness.as_str().to_string())
                .or_insert(0) += 1;
        }
        counts
    }
}

#[async_trait::async_trait]
impl SdkService for HarnessSessionService {
    fn capabilities(&self) -> SdkCapabilities {
        SdkCapabilities::default()
    }

    async fn execute(&mut self, request: SdkRequest) -> Result<Value, SdkError> {
        if request.operation == SdkOperation::Events {
            let events = self
                .poll_sdk_events()
                .await
                .into_iter()
                .map(|(_, event)| event)
                .collect::<Vec<_>>();
            return serde_json::to_value(events).map_err(|error| {
                SdkError::new(
                    SdkErrorCode::Execution,
                    request.operation,
                    error.to_string(),
                )
            });
        }
        let method = request
            .operation
            .method()
            .ok_or_else(|| SdkError::unsupported(request.operation))?;
        let result = match request.operation {
            SdkOperation::Discover | SdkOperation::Load | SdkOperation::Export => {
                self.call(method, request.params)
            }
            SdkOperation::Start
            | SdkOperation::Resume
            | SdkOperation::Input
            | SdkOperation::Interrupt
            | SdkOperation::Steer
            | SdkOperation::Respond
            | SdkOperation::Close => self.runtime_call(method, request.params).await,
            SdkOperation::Events => unreachable!("handled before method dispatch"),
        };
        result.map_err(|error| sdk_error(request.operation, error))
    }

    async fn events(&mut self) -> Result<Vec<SdkRuntimeEvent>, SdkError> {
        Ok(self
            .poll_sdk_events()
            .await
            .into_iter()
            .map(|(_, event)| event)
            .collect())
    }
}

#[cfg(feature = "adapter-api")]
struct HostedRuntimeLease {
    connection: HostedHarnessConnection,
    _host: std::sync::Arc<HostedHarnessRuntime>,
    _registration: LiveRuntimeRegistration,
    _server: crate::server::FrontendHttpServer,
}

#[async_trait::async_trait]
#[cfg(feature = "adapter-api")]
impl RuntimeConnection for HostedRuntimeLease {
    fn handle(&self) -> &crate::RuntimeHandle {
        self.connection.handle()
    }

    async fn send_input(&mut self, input: RuntimeInput) -> crate::Result<Option<String>> {
        self.connection.send_input(input).await
    }

    async fn next_event(&mut self) -> crate::Result<Option<crate::HarnessEvent>> {
        self.connection.next_event().await
    }

    async fn interrupt(&mut self) -> crate::Result<()> {
        self.connection.interrupt().await
    }

    async fn respond(&mut self, request_id: Value, response: Value) -> crate::Result<()> {
        self.connection.respond(request_id, response).await
    }

    async fn close(&mut self) -> crate::Result<()> {
        self.connection.close().await
    }
}

async fn stabilize_handshake(connection: &mut dyn RuntimeConnection) -> Result<(), String> {
    let deadline = tokio::time::Instant::now() + Duration::from_secs(3);
    loop {
        let now = tokio::time::Instant::now();
        if now >= deadline {
            return Ok(());
        }
        match tokio::time::timeout(deadline - now, connection.next_event()).await {
            Err(_) => return Ok(()),
            Ok(Ok(Some(event))) => {
                if let Some(message) = handshake_event_failure(&event) {
                    return Err(truncate_text(&message, 500));
                }
            }
            Ok(Ok(None)) => return Err("runtime transport closed during startup".into()),
            Ok(Err(error)) => return Err(error.to_string()),
        }
    }
}

fn handshake_event_failure(event: &crate::HarnessEvent) -> Option<String> {
    let detail = event
        .payload
        .get("message")
        .or_else(|| event.payload.get("line"))
        .and_then(Value::as_str)
        .unwrap_or(event.kind.as_str());
    match event.kind.as_str() {
        "transport_closed" => Some("runtime transport closed during startup".into()),
        "transport_error" => Some(format!("runtime transport error: {detail}")),
        "malformed_output" => Some(format!("runtime emitted non-protocol output: {detail}")),
        // Stderr is retained as a runtime event, but is not transport health.
        // Grok, for example, can log an AuthorizationRequired error from an
        // optional background worker while its ACP session continues to send
        // updates and complete prompts normally.
        _ => None,
    }
}

fn projected_session_result(session: &Session, options: &SessionLoadOptions) -> Value {
    let total_messages = session.messages.len();
    let (offset, end) = projected_message_window(total_messages, options);
    json!({
        "session": projected_session_json(session, options),
        "summary": projected_session_summary(session, options),
        "window": {
            "has_more": offset > 0 || end < total_messages,
            "has_newer": end < total_messages,
            "has_older": offset > 0,
            "newer_items": normalized_item_count(&session.messages[end..]),
            "offset": offset,
            "older_items": normalized_item_count(&session.messages[..offset]),
            "returned": end.saturating_sub(offset),
            "total_messages": total_messages,
        }
    })
}

fn normalized_item_count(messages: &[crate::ChatMessage]) -> usize {
    messages
        .iter()
        .map(|message| {
            let conversation = usize::from(
                matches!(message.role, Role::Assistant | Role::User)
                    && message_has_content(message),
            );
            let tool_result =
                usize::from(message.role == Role::Tool && message_has_content(message));
            conversation + tool_result + message.tool_calls().len()
        })
        .sum()
}

fn projected_session_summary(session: &Session, options: &SessionLoadOptions) -> Value {
    let mut conversational = session.messages.iter().filter(|message| {
        matches!(message.role, Role::Assistant | Role::User) && message_has_content(message)
    });
    let first_message = conversational.clone().next();
    let last_message = conversational.next_back();
    let mut assistant = session
        .messages
        .iter()
        .filter(|message| message.role == Role::Assistant && message_has_content(message));
    let first_assistant_message = assistant.clone().next();
    let last_assistant_message = assistant.next_back();
    let end_of_turn = session
        .messages
        .iter()
        .rev()
        .find(|message| message.role != Role::System)
        .is_some_and(|message| {
            message.role == Role::Assistant
                && message_has_content(message)
                && message.tool_calls().is_empty()
        });
    let project = |message: Option<&crate::ChatMessage>| {
        message.map(|message| project_inline_media(message_json(message), options))
    };
    json!({
        "end_of_turn": end_of_turn,
        "first_assistant_message": project(first_assistant_message),
        "first_message": project(first_message),
        "last_assistant_message": project(last_assistant_message),
        "last_assistant_text": last_assistant_message.map(message_text).unwrap_or_default(),
        "last_message": project(last_message),
    })
}

fn message_has_content(message: &crate::ChatMessage) -> bool {
    message
        .content
        .as_deref()
        .is_some_and(|content| !content.trim().is_empty())
        || message
            .content_parts
            .as_ref()
            .is_some_and(|parts| !parts.is_empty())
}

fn message_text(message: &crate::ChatMessage) -> String {
    if let Some(content) = &message.content {
        return content.clone();
    }
    message
        .content_parts
        .as_ref()
        .into_iter()
        .flatten()
        .filter_map(|part| part.get("text").and_then(Value::as_str))
        .collect::<Vec<_>>()
        .join("\n")
}

fn projected_session_json(session: &Session, options: &SessionLoadOptions) -> Value {
    let (offset, end) = projected_message_window(session.messages.len(), options);
    let messages = session.messages[offset..end]
        .iter()
        .map(|message| project_inline_media(message_json(message), options))
        .collect::<Vec<_>>();
    let subagents = if options.include_subagents.unwrap_or(true) {
        // The reported window describes the top-level transcript. Applying it
        // recursively would silently truncate subagents without returning a
        // window for each child. Keep their histories complete while carrying
        // the caller's media policy through the tree.
        let subagent_options = SessionLoadOptions {
            message_limit: None,
            message_offset: None,
            message_tail: None,
            ..options.clone()
        };
        session
            .subagents
            .iter()
            .map(|subagent| projected_session_json(subagent, &subagent_options))
            .collect::<Vec<_>>()
    } else {
        Vec::new()
    };
    json!({
        "source": match session.meta.source {
            SessionSource::ClaudeCode => "claude_code",
            SessionSource::Codex => "codex",
            SessionSource::Gemini => "gemini",
            SessionSource::Goose => "goose",
            SessionSource::Grok => "grok",
            SessionSource::Native => "native",
            SessionSource::OpenCode => "opencode",
            SessionSource::Pi => "pi",
        },
        "session_id": session.meta.session_id,
        "model": session.meta.model,
        "cwd": session.meta.cwd,
        "system_prompt": session.meta.system_prompt,
        "agent_id": session.meta.agent_id,
        "parent_tool_use_id": session.meta.parent_tool_use_id,
        "lineage": session.meta.lineage,
        "messages": messages,
        "subagents": subagents,
        "raw_record_count": session.raw.len(),
        "parse_error_lines": session.parse_error_lines,
    })
}

fn projected_message_window(total: usize, options: &SessionLoadOptions) -> (usize, usize) {
    if let Some(tail) = options.message_tail {
        return (total.saturating_sub(tail), total);
    }
    let offset = options.message_offset.unwrap_or(0).min(total);
    let end = options
        .message_limit
        .map(|limit| offset.saturating_add(limit).min(total))
        .unwrap_or(total);
    (offset, end)
}

fn project_inline_media(mut message: Value, options: &SessionLoadOptions) -> Value {
    let Some(parts) = message.get_mut("content").and_then(Value::as_array_mut) else {
        return message;
    };
    for part in parts {
        let Some(url) = part
            .get("image_url")
            .and_then(|image| image.get("url"))
            .and_then(Value::as_str)
        else {
            continue;
        };
        let Some(rest) = url.strip_prefix("data:") else {
            continue;
        };
        let Some((media_type, encoded)) = rest.split_once(";base64,") else {
            continue;
        };
        let padding = usize::from(encoded.ends_with('=')) + usize::from(encoded.ends_with("=="));
        let decoded_bytes = encoded.len().saturating_mul(3) / 4;
        let decoded_bytes = decoded_bytes.saturating_sub(padding);
        let should_elide = matches!(options.inline_media, InlineMediaMode::Metadata)
            || options
                .max_inline_media_bytes
                .is_some_and(|limit| decoded_bytes > limit);
        if should_elide {
            *part = json!({
                "type": "media_reference",
                "media_type": media_type,
                "encoding": "base64",
                "encoded_bytes": encoded.len(),
                "decoded_bytes": decoded_bytes,
                "omitted": true,
            });
        }
    }
    message
}

#[derive(Deserialize)]
struct LocatorParams {
    locator: SessionLocator,
    /// Optional fidelity for the READ surfaces (`sessions.load`,
    /// `sessions.follow`).
    ///
    /// Omitted means [`Fidelity::Semantic`]: these two methods only ever
    /// produce a read-only view, and a compacted or resumed-across-files
    /// transcript — the everyday shape of a long Claude Code session — has no
    /// losslessly reconstructable record graph, so refusing to render it made
    /// the mirror unusable rather than accurate. A caller that intends to
    /// CONTINUE from what it reads asks for a lossless level explicitly and
    /// gets the strict refusal back. Every other method (export, translate,
    /// branch, handoff, resume_instructions) is lossless-only and has no
    /// such knob.
    #[serde(default)]
    fidelity: Option<Fidelity>,
    /// Optional bounded frontend projection. Absent preserves the historical
    /// complete-session read contract.
    #[serde(default)]
    view: Option<SessionReadView>,
}

#[derive(Deserialize)]
struct SessionReadView {
    /// Number of trailing normalized messages to return. Zero is treated as
    /// one so a caller cannot accidentally request an unbounded empty mode.
    #[serde(default)]
    tail_messages: Option<usize>,
    /// Whether Claude Code child transcripts belong in this view. The
    /// frontend default is false; the legacy no-view path remains true.
    #[serde(default)]
    include_subagents: bool,
    /// Preserve human-visible native history across model-context compaction.
    #[serde(default)]
    display_history: bool,
    /// Bound each individual text field so a single tool result cannot turn a
    /// small message window into a hundred-megabyte RPC response.
    #[serde(default)]
    max_message_chars: Option<usize>,
}

impl LocatorParams {
    fn read_fidelity(&self) -> Fidelity {
        self.fidelity.unwrap_or(Fidelity::Semantic)
    }

    fn include_subagents(&self) -> bool {
        self.view
            .as_ref()
            .map(|view| view.include_subagents)
            .unwrap_or(true)
    }

    fn tail_messages(&self) -> Option<usize> {
        self.view
            .as_ref()
            .and_then(|view| view.tail_messages)
            .map(|limit| limit.clamp(1, 5_000))
    }

    fn display_history(&self) -> bool {
        self.view.as_ref().is_some_and(|view| view.display_history)
    }

    fn max_message_chars(&self) -> Option<usize> {
        self.view
            .as_ref()
            .and_then(|view| view.max_message_chars)
            .map(|limit| limit.clamp(256, 64_000))
    }

    fn bound_session(&self, session: &mut Session) {
        bound_session_view(session, self.tail_messages(), self.max_message_chars());
    }
}

#[derive(Debug, Clone, Copy, Default, Deserialize)]
#[serde(rename_all = "snake_case")]
enum InlineMediaMode {
    #[default]
    Full,
    Metadata,
}

#[derive(Debug, Clone, Default, Deserialize)]
#[serde(default)]
struct SessionLoadOptions {
    include_subagents: Option<bool>,
    inline_media: InlineMediaMode,
    max_inline_media_bytes: Option<usize>,
    message_limit: Option<usize>,
    message_offset: Option<usize>,
    message_tail: Option<usize>,
}

impl SessionLoadOptions {
    fn validate(&self) -> std::result::Result<(), ServiceError> {
        if self.message_tail.is_some()
            && (self.message_limit.is_some() || self.message_offset.is_some())
        {
            return Err(ServiceError::InvalidParams(
                "sessions.load options.message_tail cannot be combined with message_limit or message_offset"
                    .into(),
            ));
        }
        Ok(())
    }
}

#[derive(Deserialize)]
struct LoadSessionParams {
    #[serde(flatten)]
    read: LocatorParams,
    #[serde(default)]
    options: Option<SessionLoadOptions>,
}

#[derive(Deserialize)]
struct UnfollowParams {
    subscription: String,
}

#[derive(Deserialize)]
struct MessageSessionParams {
    locator: SessionLocator,
    text: String,
    /// Same storage roots discovery accepts, so a caller (and a test) can
    /// point the live-session registry somewhere other than `$HOME`.
    #[serde(default)]
    homes: crate::HarnessHomes,
}

/// Deliver `text` into a session that is running right now, or say why not.
///
/// A refusal is a RESULT, not a JSON-RPC error: "that session is persisted
/// only" is an answer about the session, which a mirror renders next to the
/// transcript, and this service's error envelope carries no structured data
/// field a machine-readable reason could survive in.
///
/// `delivered_to_bus` is the honest ceiling of what the courier proves. The
/// message reached the receiving session's inbox; whether that session ever
/// reads it is governed by ITS OWN inbound controls (`crossSessionInbound`,
/// approval dialogs), which Supercode neither sees nor overrides.
#[cfg(feature = "adapter-api")]
async fn message_live_session(
    params: &MessageSessionParams,
    runner: &dyn crate::claude_peer::CourierRunner,
) -> Value {
    if params.locator.harness.as_str() != HarnessId::CLAUDE_CODE {
        return json!({
            "delivered_to_bus": false,
            "refusal": {
                "reason": crate::claude_peer::ClaudePeerRefusal::HarnessUnsupported.as_str(),
                "message": format!(
                    "`{}` does not publish a live-session registry; only claude-code sessions can be messaged in place",
                    params.locator.harness.as_str()
                ),
            },
        });
    }
    match crate::claude_peer::message_claude_peer(
        &params.homes,
        &params.locator.session_id,
        &params.text,
        runner,
    )
    .await
    {
        Ok(delivery) => json!({
            "delivered_to_bus": true,
            "target": {
                "session_id": delivery.target.session_id,
                "name": delivery.target.name,
                "pid": delivery.target.pid,
                "cwd": delivery.target.cwd,
                "status": delivery.target.status.map(|status| status.as_str()),
            },
            "courier": {
                "model": crate::claude_peer::COURIER_MODEL,
                "report": delivery.courier_report,
            },
        }),
        Err(refusal) => json!({
            "delivered_to_bus": false,
            "refusal": {"reason": refusal.reason.as_str(), "message": refusal.message},
        }),
    }
}

/// Source identity of one follow subscription, plus the last lifecycle state
/// already reported on it. The follower itself stays purely persistence-facing.
// Only the adapter-api poll reads these; the subscription bookkeeping itself is
// shared by both builds.
#[cfg_attr(not(feature = "adapter-api"), allow(dead_code))]
struct FollowedSource {
    harness: String,
    session_id: String,
    reported: Option<String>,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Deserialize)]
#[serde(rename_all = "kebab-case")]
enum TransferFormat {
    ClaudeCode,
    Codex,
    #[serde(rename = "opencode", alias = "open-code")]
    OpenCode,
    Pi,
    Grok,
    Gemini,
    Goose,
}

impl TransferFormat {
    fn id(self) -> &'static str {
        match self {
            Self::ClaudeCode => HarnessId::CLAUDE_CODE,
            Self::Codex => HarnessId::CODEX,
            Self::OpenCode => HarnessId::OPENCODE,
            Self::Pi => HarnessId::PI,
            Self::Grok => HarnessId::GROK,
            Self::Gemini => HarnessId::GEMINI,
            Self::Goose => HarnessId::GOOSE,
        }
    }
}

impl From<TransferFormat> for SessionFormat {
    fn from(value: TransferFormat) -> Self {
        match value {
            TransferFormat::ClaudeCode => Self::ClaudeCode,
            TransferFormat::Codex => Self::Codex,
            TransferFormat::OpenCode => Self::OpenCode,
            TransferFormat::Pi => Self::Pi,
            TransferFormat::Grok => Self::Grok,
            TransferFormat::Gemini => Self::Gemini,
            TransferFormat::Goose => Self::Goose,
        }
    }
}

#[derive(Deserialize)]
struct ImportSessionParams {
    source_harness: TransferFormat,
    content: String,
}

#[derive(Deserialize)]
struct ExportSessionParams {
    locator: SessionLocator,
    target_harness: TransferFormat,
}

#[derive(Deserialize)]
struct ReduceSessionParams {
    locator: SessionLocator,
    target_harness: TransferFormat,
    #[serde(default = "default_keep_last")]
    keep_last: usize,
}

fn default_keep_last() -> usize {
    6
}

#[derive(Deserialize)]
struct BranchSessionParams {
    locator: SessionLocator,
    #[serde(default)]
    target_harness: Option<TransferFormat>,
}

#[derive(Deserialize)]
struct HandoffSessionParams {
    locator: SessionLocator,
    target_harness: TransferFormat,
    #[serde(default)]
    cwd: Option<PathBuf>,
}

#[derive(Debug, Clone, Copy, Default, Deserialize)]
#[serde(rename_all = "snake_case")]
enum ResumePolicy {
    #[default]
    Default,
    Yolo,
}

#[derive(Deserialize)]
struct ResumeInstructionsParams {
    locator: SessionLocator,
    #[serde(default)]
    cwd: Option<PathBuf>,
    #[serde(default)]
    policy: ResumePolicy,
}

#[derive(Serialize)]
struct SessionArtifact {
    source_harness: HarnessId,
    target_harness: &'static str,
    session_id: Option<String>,
    content: String,
    suggested_filename: String,
    files: Vec<SessionArtifactFile>,
    fidelity: Fidelity,
    residue: Vec<String>,
}

#[derive(Serialize)]
struct SessionArtifactFile {
    path: String,
    content: String,
    role: ArtifactFileRole,
}

#[derive(Serialize)]
#[serde(rename_all = "snake_case")]
enum ArtifactFileRole {
    Primary,
    Subagent,
    Bundle,
    SourceRecovery,
}

#[derive(Serialize)]
struct StructuredLaunch {
    cwd: PathBuf,
    program: String,
    arguments: Vec<String>,
    env: BTreeMap<String, String>,
}

struct HandoffInstructions {
    launch: StructuredLaunch,
    materialize: Option<StructuredLaunch>,
    requires_materialization: bool,
    note: String,
}

#[derive(Debug, Clone, Copy, Default, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "snake_case")]
enum HarnessProbeLevel {
    #[default]
    Passive,
    Handshake,
}

#[derive(Default, Deserialize)]
#[serde(default)]
struct HarnessInventoryParams {
    harness: Option<HarnessId>,
    harnesses: Vec<HarnessId>,
    workspace: Option<PathBuf>,
    probe: HarnessProbeLevel,
    include_sessions: bool,
    /// Omit subprocess-based `--version` calls when a latency-sensitive UI only needs readiness.
    skip_versions: bool,
}

#[derive(Serialize)]
struct HarnessInventoryReport {
    probe: HarnessProbeLevel,
    workspace: Option<PathBuf>,
    harnesses: Vec<LocalHarness>,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
#[serde(rename_all = "snake_case")]
enum HarnessAuthState {
    Ready,
    Configured,
    Required,
    Unknown,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize)]
#[serde(rename_all = "snake_case")]
enum HarnessRuntimeState {
    Ready,
    Degraded,
    Unavailable,
}

#[derive(Serialize)]
struct HarnessSessionCounts {
    global: Option<usize>,
    workspace: Option<usize>,
}

#[derive(Serialize)]
struct LocalHarness {
    id: HarnessId,
    display_name: String,
    supported: bool,
    installed: bool,
    executable: Option<String>,
    version: Option<String>,
    auth: HarnessAuthState,
    runtime: HarnessRuntimeState,
    protocol: String,
    capabilities: crate::RuntimeCapabilities,
    effective_capabilities: crate::RuntimeCapabilities,
    sessions: HarnessSessionCounts,
    reason: Option<String>,
    repair: Option<String>,
}

#[derive(Clone, Deserialize)]
struct RuntimeBackendParams {
    harness: HarnessId,
    #[serde(default)]
    protocol: Option<String>,
    #[serde(default)]
    launch: Option<RuntimeLaunch>,
    #[serde(default)]
    base_url: Option<String>,
    #[serde(default)]
    policy: RuntimePolicy,
}

#[derive(Debug, Clone, Copy, Default, Deserialize)]
#[serde(rename_all = "snake_case")]
enum RuntimePolicy {
    #[default]
    Default,
    Yolo,
}

#[derive(Deserialize)]
struct RuntimeStartParams {
    #[serde(flatten)]
    backend: RuntimeBackendParams,
    cwd: PathBuf,
}

#[derive(Deserialize)]
struct RuntimeAttachParams {
    #[serde(flatten)]
    backend: RuntimeBackendParams,
    runtime_id: String,
    #[serde(default)]
    cwd: Option<PathBuf>,
}

#[derive(Deserialize)]
struct RuntimeConnectionParams {
    connection: String,
}

#[derive(Deserialize)]
struct RuntimeInputParams {
    connection: String,
    text: String,
}

#[derive(Deserialize)]
struct RuntimeRespondParams {
    connection: String,
    request_id: Value,
    response: Value,
}

fn default_reduction_store_root() -> PathBuf {
    if let Some(root) = std::env::var_os("SUPERCODE_HOME") {
        return PathBuf::from(root).join("sessions");
    }
    if let Some(home) = std::env::var_os("HOME") {
        return PathBuf::from(home).join(".supercode").join("sessions");
    }
    PathBuf::from(".supercode").join("sessions")
}

fn messages_jsonl(messages: &[crate::ChatMessage]) -> std::result::Result<String, ServiceError> {
    let mut output = String::new();
    for message in messages {
        output.push_str(
            &serde_json::to_string(message)
                .map_err(|error| ServiceError::Operation(error.to_string()))?,
        );
        output.push('\n');
    }
    Ok(output)
}

fn parse_messages_jsonl(
    content: &str,
) -> std::result::Result<Vec<crate::ChatMessage>, ServiceError> {
    content
        .lines()
        .enumerate()
        .filter(|(_, line)| !line.trim().is_empty())
        .map(|(index, line)| {
            serde_json::from_str::<crate::ChatMessage>(line).map_err(|error| {
                ServiceError::Operation(format!(
                    "reduced transcript line {} is invalid: {error}",
                    index + 1
                ))
            })
        })
        .collect()
}

fn reduced_bootstrap_prompt(
    source: &SessionLocator,
    target: TransferFormat,
    view_jsonl: &str,
    sidecar_path: &Path,
    reduction_log_path: &Path,
) -> String {
    format!(
        "Continue the work from this losslessly reduced {source_harness} session in {target_harness}.\n\
         \n\
         The bounded working transcript is below. Treat reduction markers as transparent placeholders, not missing work. If a detail behind a marker is needed, use ordinary file-reading/search tools against the full Supercode sidecar at `{sidecar}` and its reduction index at `{log}`. Do not guess hidden content. Both files were reloaded and verified before this continuation was issued.\n\
         \n\
         <supercode-reduced-session source-session=\"{source_id}\">\n\
         {view_jsonl}\
         </supercode-reduced-session>\n\
         \n\
         Resume from the latest unresolved user request and preserve the source session's decisions and constraints.",
        source_harness = source.harness.as_str(),
        target_harness = target.id(),
        sidecar = sidecar_path.display(),
        log = reduction_log_path.display(),
        source_id = source.session_id,
    )
}

fn session_artifact(
    locator: &SessionLocator,
    session: &Session,
    target: TransferFormat,
) -> std::result::Result<SessionArtifact, ServiceError> {
    session_artifact_with_id(locator, session, target, None)
}

fn session_artifact_with_id(
    locator: &SessionLocator,
    session: &Session,
    target: TransferFormat,
    target_session_id: Option<&str>,
) -> std::result::Result<SessionArtifact, ServiceError> {
    let format: SessionFormat = target.into();
    let diagonal = format.source() == session.meta.source;
    let has_appended_turns = session
        .imported_message_count
        .is_some_and(|imported| imported < session.messages.len());
    let content = if let Some(id) = target_session_id {
        if diagonal && format != SessionFormat::OpenCode {
            session
                .to_jsonl_spliced(format, Some(id))
                .map_err(operation)?
        } else {
            let mut rewritten = session.clone();
            rewritten.meta.session_id = Some(id.to_string());
            rewritten.to_jsonl(format).map_err(operation)?
        }
    } else if diagonal && session.raw_is_verbatim && !has_appended_turns {
        session.raw_verbatim()
    } else if diagonal {
        session.to_jsonl_spliced(format, None).map_err(operation)?
    } else {
        session.to_jsonl(format).map_err(operation)?
    };
    let stem = sanitize_filename(
        target_session_id
            .or(session.meta.session_id.as_deref())
            .unwrap_or(&locator.session_id),
    );
    let suggested_filename = if diagonal && target == TransferFormat::Grok {
        "chat_history.jsonl".to_string()
    } else if target == TransferFormat::Goose {
        format!("{stem}.goose.json")
    } else {
        format!("{stem}.{}.jsonl", target.id())
    };
    let mut files = vec![SessionArtifactFile {
        path: suggested_filename.clone(),
        content: content.clone(),
        role: ArtifactFileRole::Primary,
    }];
    if target == TransferFormat::ClaudeCode {
        let bundle_stem = Path::new(&suggested_filename)
            .file_stem()
            .and_then(|stem| stem.to_str())
            .unwrap_or(&stem);
        let mut child_paths = BTreeSet::new();
        for (index, subagent) in session.subagents.iter().enumerate() {
            let agent_id = subagent
                .meta
                .agent_id
                .as_deref()
                .map(|id| id.strip_prefix("agent-").unwrap_or(id))
                .map(sanitize_filename)
                .filter(|id| !id.is_empty())
                .unwrap_or_else(|| format!("subagent-{}", index + 1));
            let child_has_appended_turns = subagent
                .imported_message_count
                .is_some_and(|imported| imported < subagent.messages.len());
            let child_content = if target_session_id.is_none()
                && subagent.meta.source == SessionSource::ClaudeCode
                && subagent.raw_is_verbatim
                && !child_has_appended_turns
            {
                subagent.raw_verbatim()
            } else if subagent.meta.source == SessionSource::ClaudeCode {
                subagent
                    .to_jsonl_spliced(SessionFormat::ClaudeCode, target_session_id)
                    .map_err(operation)?
            } else {
                let mut child = subagent.clone();
                if let Some(id) = target_session_id {
                    child.meta.session_id = Some(id.to_string());
                }
                child
                    .to_jsonl(SessionFormat::ClaudeCode)
                    .map_err(operation)?
            };
            let path = format!("{bundle_stem}/subagents/agent-{agent_id}.jsonl");
            if !child_paths.insert(path.clone()) {
                return Err(ServiceError::Operation(format!(
                    "Claude subagent ids collide at artifact path `{path}`"
                )));
            }
            files.push(SessionArtifactFile {
                path,
                content: child_content,
                role: ArtifactFileRole::Subagent,
            });
        }
    }
    if diagonal && target == TransferFormat::Grok {
        append_grok_bundle_files(locator, "", ArtifactFileRole::Bundle, &mut files)?;
    }
    if !diagonal || !session.raw_is_verbatim {
        files.push(SessionArtifactFile {
            path: "recovery/source.supercode.jsonl".into(),
            content: session.to_native_jsonl(),
            role: ArtifactFileRole::SourceRecovery,
        });
        for (index, subagent) in session.subagents.iter().enumerate() {
            let id = subagent
                .meta
                .agent_id
                .as_deref()
                .map(sanitize_filename)
                .unwrap_or_else(|| format!("subagent-{}", index + 1));
            files.push(SessionArtifactFile {
                path: format!("recovery/subagents/{id}.supercode.jsonl"),
                content: subagent.to_native_jsonl(),
                role: ArtifactFileRole::SourceRecovery,
            });
        }
    }
    if !diagonal && session.meta.source == SessionSource::Grok {
        append_grok_bundle_files(
            locator,
            "recovery/grok/",
            ArtifactFileRole::SourceRecovery,
            &mut files,
        )?;
    }
    let (fidelity, residue) = if diagonal
        && target_session_id.is_none()
        && session.raw_is_verbatim
        && !has_appended_turns
    {
        (Fidelity::ByteLossless, Vec::new())
    } else if diagonal && !(target_session_id.is_some() && target == TransferFormat::OpenCode) {
        (
            Fidelity::ValueLossless,
            vec![if target_session_id.is_some() {
                "target identity was rewritten, so the artifact intentionally differs from source bytes".into()
            } else {
                "source storage was reconstructed as a native-value-equivalent export; original container bytes were not captured".into()
            }],
        )
    } else {
        (
            Fidelity::Semantic,
            vec!["target schema has no portable slot for every source-native record and metadata field".into()],
        )
    };
    Ok(SessionArtifact {
        source_harness: locator.harness.clone(),
        target_harness: target.id(),
        session_id: target_session_id
            .map(str::to_string)
            .or_else(|| session.meta.session_id.clone()),
        content,
        suggested_filename,
        files,
        fidelity,
        residue,
    })
}

fn append_grok_bundle_files(
    locator: &SessionLocator,
    prefix: &str,
    role: ArtifactFileRole,
    files: &mut Vec<SessionArtifactFile>,
) -> std::result::Result<(), ServiceError> {
    let primary = locator.storage.path();
    if primary.file_name().and_then(|name| name.to_str()) != Some("chat_history.jsonl") {
        return Err(ServiceError::Operation(format!(
            "Grok bundle locator must name chat_history.jsonl, got {}",
            primary.display()
        )));
    }
    let parent = primary.parent().ok_or_else(|| {
        ServiceError::Operation("Grok chat_history.jsonl has no session directory".into())
    })?;
    for name in ["summary.json", "updates.jsonl"] {
        let path = parent.join(name);
        let metadata = match std::fs::symlink_metadata(&path) {
            Ok(metadata) => metadata,
            Err(error) if error.kind() == std::io::ErrorKind::NotFound => continue,
            Err(error) => return Err(ServiceError::Operation(error.to_string())),
        };
        if metadata.file_type().is_symlink() || !metadata.is_file() {
            return Err(ServiceError::Operation(format!(
                "refusing non-regular Grok bundle member {}",
                path.display()
            )));
        }
        let content = std::fs::read_to_string(&path).map_err(|error| {
            ServiceError::Operation(format!(
                "Grok bundle member {} is not representable as UTF-8: {error}",
                path.display()
            ))
        })?;
        files.push(SessionArtifactFile {
            path: format!("{prefix}{name}"),
            content,
            role: match role {
                ArtifactFileRole::Bundle => ArtifactFileRole::Bundle,
                _ => ArtifactFileRole::SourceRecovery,
            },
        });
    }
    Ok(())
}

fn handoff_artifact(
    locator: &SessionLocator,
    session: &Session,
    target: TransferFormat,
    cwd: &Path,
) -> std::result::Result<SessionArtifact, ServiceError> {
    if target != TransferFormat::Grok {
        let target_session_id = target_session_id(target);
        return session_artifact_with_id(locator, session, target, Some(&target_session_id));
    }

    // Stock Grok's importer accepts Claude/Codex transcripts and materializes its own
    // multi-file session bundle. A synthesized Grok chat_history.jsonl alone is not a
    // resumable handoff because updates.jsonl is the authoritative restore log.
    let mut importable = session.clone();
    // The Claude importer validates sessionId as a UUID. Source harness identities
    // are not portable (OpenCode, for example, uses `ses_...`), and a handoff must
    // not overwrite an existing target session when the source already uses UUIDs.
    // Mint a distinct target identity and still bind the importer-returned ID at
    // launch time because the importer remains the authority on materialization.
    importable.meta.session_id = Some(target_session_id(TransferFormat::ClaudeCode));
    importable.meta.cwd = Some(if cwd.is_absolute() {
        cwd.to_path_buf()
    } else {
        std::env::current_dir()
            .map_err(|error| ServiceError::Operation(error.to_string()))?
            .join(cwd)
    });
    let content = importable
        .to_jsonl(SessionFormat::ClaudeCode)
        .map_err(operation)?;
    let stem = sanitize_filename(
        importable
            .meta
            .session_id
            .as_deref()
            .unwrap_or(&locator.session_id),
    );
    let suggested_filename = format!("{stem}.grok-import.claude-code.jsonl");
    Ok(SessionArtifact {
        source_harness: locator.harness.clone(),
        // This names the artifact's actual wire format. The requested handoff target
        // remains Grok; its official importer is the materialization boundary.
        target_harness: TransferFormat::ClaudeCode.id(),
        session_id: importable.meta.session_id.clone(),
        content: content.clone(),
        suggested_filename: suggested_filename.clone(),
        files: vec![SessionArtifactFile {
            path: suggested_filename,
            content,
            role: ArtifactFileRole::Primary,
        }],
        fidelity: Fidelity::Semantic,
        residue: vec!["Grok's stock importer accepts a Claude Code transcript, not a complete Grok updates/session bundle".into()],
    })
}

fn target_session_id(target: TransferFormat) -> String {
    let uuid = generated_session_id();
    match target {
        TransferFormat::OpenCode => format!("ses_{}", uuid.replace('-', "")),
        TransferFormat::ClaudeCode
        | TransferFormat::Codex
        | TransferFormat::Pi
        | TransferFormat::Grok
        | TransferFormat::Gemini
        | TransferFormat::Goose => uuid,
    }
}

fn sanitize_filename(value: &str) -> String {
    let value = value
        .chars()
        .map(|character| {
            if character.is_ascii_alphanumeric() || matches!(character, '-' | '_') {
                character
            } else {
                '-'
            }
        })
        .collect::<String>();
    let value = value.trim_matches('-');
    if value.is_empty() {
        "session".into()
    } else {
        value.chars().take(100).collect()
    }
}

fn handoff_instructions(
    target: TransferFormat,
    session_id: &str,
    cwd: &Path,
) -> HandoffInstructions {
    let launch = |program: &str, arguments: Vec<String>| StructuredLaunch {
        cwd: cwd.to_path_buf(),
        program: program.into(),
        arguments,
        env: BTreeMap::new(),
    };
    match target {
        TransferFormat::ClaudeCode => HandoffInstructions {
            launch: launch("claude", vec!["--resume".into(), session_id.into()]),
            materialize: None,
            requires_materialization: true,
            note: "Write the artifact into Claude Code's native project session store before running the resume launch; Claude Code has no general transcript-import command.".into(),
        },
        TransferFormat::Codex => HandoffInstructions {
            launch: launch("codex", vec!["resume".into(), session_id.into()]),
            materialize: None,
            requires_materialization: true,
            note: "Write the artifact into Codex's native rollout store before running the resume launch; Codex has no general transcript-import command.".into(),
        },
        TransferFormat::OpenCode => HandoffInstructions {
            launch: launch("opencode", vec!["--session".into(), session_id.into()]),
            materialize: Some(launch(
                "opencode",
                vec!["import".into(), "{artifact_path}".into()],
            )),
            requires_materialization: true,
            note: "Write the artifact to a file, run the materialize command with its path, then launch the imported session.".into(),
        },
        TransferFormat::Pi => HandoffInstructions {
            launch: launch("pi", vec!["--session".into(), "{artifact_path}".into()]),
            materialize: None,
            requires_materialization: true,
            note: "Write the artifact to a file and replace {artifact_path} in the launch arguments; Pi can resume that file directly.".into(),
        },
        TransferFormat::Grok => HandoffInstructions {
            launch: launch(
                "grok",
                vec![
                    "--resume".into(),
                    "{imported_session_id}".into(),
                    "--fork-session".into(),
                ],
            ),
            materialize: Some(launch(
                "grok",
                vec!["import".into(), "--json".into(), "{artifact_path}".into()],
            )),
            requires_materialization: true,
            note: "The artifact is Claude Code JSONL for Grok's official importer. Write it to a file, run the materialize command, read sessionId from its NDJSON outcome=imported record, replace {imported_session_id} in the launch arguments, then launch a writable fork of the imported session.".into(),
        },
        TransferFormat::Gemini => HandoffInstructions {
            launch: launch(
                "gemini",
                vec!["--session-file".into(), "{artifact_path}".into()],
            ),
            materialize: None,
            requires_materialization: true,
            note: "Write the Gemini JSONL artifact to a file and replace {artifact_path}; Gemini imports it into the current project's chat store before opening the continuation.".into(),
        },
        TransferFormat::Goose => HandoffInstructions {
            launch: launch(
                "goose",
                vec![
                    "session".into(),
                    "--resume".into(),
                    "--session-id".into(),
                    "{imported_session_id}".into(),
                ],
            ),
            materialize: Some(launch(
                "goose",
                vec!["session".into(), "import".into(), "{artifact_path}".into()],
            )),
            requires_materialization: true,
            note: "Write the Goose JSON artifact to a file, run the materialize command, read the imported session id from its output, replace {imported_session_id}, then resume that native Goose session.".into(),
        },
    }
}

fn resume_launch(
    harness: &str,
    session_id: &str,
    cwd: &Path,
    policy: ResumePolicy,
) -> std::result::Result<StructuredLaunch, ServiceError> {
    let mut arguments = Vec::new();
    let program = match harness {
        HarnessId::GROK => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.extend([
                    "--sandbox".into(),
                    "workspace".into(),
                    "--always-approve".into(),
                ]);
            }
            arguments.extend(["--resume".into(), session_id.into()]);
            "grok"
        }
        HarnessId::CODEX => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.extend([
                    "--dangerously-bypass-approvals-and-sandbox".into(),
                    "--dangerously-bypass-hook-trust".into(),
                ]);
            }
            arguments.extend(["resume".into(), session_id.into()]);
            "codex"
        }
        HarnessId::CLAUDE_CODE => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.push("--dangerously-skip-permissions".into());
            }
            arguments.extend(["--resume".into(), session_id.into()]);
            "claude"
        }
        HarnessId::GEMINI => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.push("--yolo".into());
            }
            arguments.extend(["--resume".into(), session_id.into()]);
            "gemini"
        }
        HarnessId::GOOSE => {
            arguments.extend([
                "session".into(),
                "--resume".into(),
                "--session-id".into(),
                session_id.into(),
            ]);
            "goose"
        }
        HarnessId::PI => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.push("--approve".into());
            }
            arguments.extend(["--session".into(), session_id.into()]);
            "pi"
        }
        HarnessId::OPENCODE => {
            arguments.extend(["--session".into(), session_id.into()]);
            "opencode"
        }
        HarnessId::SUPERCODE => {
            if matches!(policy, ResumePolicy::Yolo) {
                arguments.push("--dangerous".into());
            }
            arguments.extend(["resume".into(), session_id.into()]);
            "supercode"
        }
        other => {
            return Err(ServiceError::InvalidParams(format!(
                "no structured resume launch is registered for harness `{other}`"
            )))
        }
    };
    Ok(StructuredLaunch {
        cwd: cwd.to_path_buf(),
        program: program.into(),
        arguments,
        env: BTreeMap::new(),
    })
}

fn runtime_backend(
    params: &RuntimeBackendParams,
) -> std::result::Result<Box<dyn RuntimeBackend>, ServiceError> {
    if params.protocol.as_deref() == Some("acp") {
        let launch = params
            .launch
            .clone()
            .or_else(|| {
                harness_support_registry()
                    .harnesses
                    .into_iter()
                    .find(|harness| harness.id == params.harness)
                    .filter(|harness| {
                        harness.runtime.implementation == ImplementationKind::GenericProtocol
                            && harness.runtime.protocol.starts_with("acp")
                    })
                    .and_then(|harness| harness.runtime.default_launch)
            })
            .ok_or_else(|| {
                ServiceError::InvalidParams(
                    "an ACP runtime requires `launch` unless the harness has a registered default"
                        .into(),
                )
            })?;
        let resume_session = harness_support_registry()
            .harnesses
            .into_iter()
            .find(|harness| harness.id == params.harness)
            .is_some_and(|harness| harness.runtime.capabilities.resume_session);
        return Ok(Box::new(
            AcpRuntimeBackend::new(params.harness.clone(), launch)
                .with_resume_support(resume_session),
        ));
    }
    let backend: Box<dyn RuntimeBackend> = match params.harness.as_str() {
        HarnessId::CODEX => Box::new(CodexRuntimeBackend::new()),
        HarnessId::CLAUDE_CODE => Box::new(ClaudeCodeRuntimeBackend::new()),
        HarnessId::PI => Box::new(PiRuntimeBackend::new()),
        HarnessId::OPENCODE => match &params.base_url {
            Some(url) => Box::new(OpenCodeRuntimeBackend::connect(url)),
            None => Box::new(OpenCodeRuntimeBackend::new()),
        },
        harness => {
            let descriptor = harness_support_registry()
                .harnesses
                .into_iter()
                .find(|descriptor| descriptor.id.as_str() == harness)
                .filter(|descriptor| {
                    descriptor.runtime.implementation == ImplementationKind::GenericProtocol
                        && descriptor.runtime.protocol.starts_with("acp")
                });
            let Some(descriptor) = descriptor else {
                return Err(ServiceError::InvalidParams(format!(
                    "no runtime adapter for harness `{harness}`; use protocol `acp` with a launch command"
                )));
            };
            let resume = descriptor.runtime.capabilities.resume_session;
            Box::new(
                AcpRuntimeBackend::new(
                    descriptor.id,
                    descriptor
                        .runtime
                        .default_launch
                        .expect("generic ACP registry entry includes its launch"),
                )
                .with_resume_support(resume),
            )
        }
    };
    Ok(backend)
}

fn runtime_launch(params: &RuntimeBackendParams) -> Option<RuntimeLaunch> {
    if let Some(launch) = &params.launch {
        return Some(launch.clone());
    }
    if !matches!(params.policy, RuntimePolicy::Yolo) {
        return None;
    }
    let launch = match params.harness.as_str() {
        HarnessId::GROK => RuntimeLaunch {
            program: "grok".into(),
            arguments: vec![
                "--sandbox".into(),
                "workspace".into(),
                "--always-approve".into(),
                "agent".into(),
                "--no-leader".into(),
                "stdio".into(),
            ],
            env: BTreeMap::from([("GROK_AGENT_DASHBOARD".into(), "0".into())]),
        },
        HarnessId::CODEX => RuntimeLaunch {
            program: "codex".into(),
            arguments: vec![
                "--dangerously-bypass-approvals-and-sandbox".into(),
                "--dangerously-bypass-hook-trust".into(),
                "app-server".into(),
            ],
            env: BTreeMap::new(),
        },
        HarnessId::CLAUDE_CODE => RuntimeLaunch {
            program: "claude".into(),
            arguments: vec![
                "--dangerously-skip-permissions".into(),
                "--print".into(),
                "--input-format".into(),
                "stream-json".into(),
                "--output-format".into(),
                "stream-json".into(),
                "--verbose".into(),
            ],
            env: BTreeMap::new(),
        },
        HarnessId::PI => RuntimeLaunch {
            program: "pi".into(),
            arguments: vec!["--approve".into(), "--mode".into(), "rpc".into()],
            env: BTreeMap::new(),
        },
        HarnessId::OPENCODE => RuntimeLaunch {
            program: "opencode".into(),
            arguments: vec!["serve".into()],
            env: BTreeMap::new(),
        },
        HarnessId::GEMINI => RuntimeLaunch {
            program: "gemini".into(),
            arguments: vec!["--acp".into(), "--yolo".into()],
            env: BTreeMap::new(),
        },
        HarnessId::GOOSE => RuntimeLaunch {
            program: "goose".into(),
            arguments: vec!["acp".into()],
            env: BTreeMap::new(),
        },
        HarnessId::SUPERCODE => RuntimeLaunch {
            program: "supercode".into(),
            arguments: vec!["acp".into(), "--dangerous".into()],
            env: BTreeMap::new(),
        },
        _ => return None,
    };
    Some(launch)
}

/// Disposable harness state for a no-prompt readiness probe. Merely opening
/// several stock CLIs writes a session header or migrates configuration, so a
/// handshake must never point at the user's real home. Authentication files
/// are copied into the private temporary home; all writes disappear with the
/// guard after the connection closes.
struct IsolatedProbeHome {
    launch: RuntimeLaunch,
    root: PathBuf,
}

impl IsolatedProbeHome {
    fn new(harness: &str, mut launch: RuntimeLaunch) -> std::io::Result<Self> {
        let root = std::env::temp_dir().join(format!(
            "supercode-harness-probe-{harness}-{}",
            generated_session_id()
        ));
        std::fs::create_dir_all(&root)?;
        set_private_dir_permissions(&root)?;

        if let Some(source_home) = std::env::var_os("HOME").map(PathBuf::from) {
            for relative in probe_auth_files(harness) {
                copy_probe_file(&source_home, &root, relative)?;
            }
        }
        configure_isolated_probe_auth(harness, &root)?;

        let root_text = root.to_string_lossy().into_owned();
        for (key, value) in [
            ("HOME", root_text.clone()),
            (
                "XDG_CACHE_HOME",
                root.join(".cache").to_string_lossy().into_owned(),
            ),
            (
                "XDG_CONFIG_HOME",
                root.join(".config").to_string_lossy().into_owned(),
            ),
            (
                "XDG_DATA_HOME",
                root.join(".local/share").to_string_lossy().into_owned(),
            ),
        ] {
            launch.env.insert(key.into(), value);
        }
        let scoped = match harness {
            HarnessId::CLAUDE_CODE => Some(("CLAUDE_CONFIG_DIR", root.join(".claude"))),
            HarnessId::CODEX => Some(("CODEX_HOME", root.join(".codex"))),
            HarnessId::GEMINI => Some(("GEMINI_CLI_HOME", root.clone())),
            HarnessId::GROK => Some(("GROK_HOME", root.join(".grok"))),
            HarnessId::PI => Some(("PI_CODING_AGENT_DIR", root.join(".pi/agent"))),
            HarnessId::SUPERCODE => Some(("SUPERCODE_HOME", root.join(".config/supercode"))),
            _ => None,
        };
        if let Some((key, value)) = scoped {
            launch
                .env
                .insert(key.into(), value.to_string_lossy().into_owned());
        }
        Ok(Self { launch, root })
    }

    fn cleanup(&self) -> std::io::Result<()> {
        match std::fs::remove_dir_all(&self.root) {
            Ok(()) => Ok(()),
            Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(()),
            Err(error) => Err(error),
        }
    }
}

impl Drop for IsolatedProbeHome {
    fn drop(&mut self) {
        let _ = self.cleanup();
    }
}

fn probe_auth_files(harness: &str) -> &'static [&'static str] {
    match harness {
        HarnessId::CLAUDE_CODE => &[".claude/.credentials.json", ".claude.json"],
        HarnessId::CODEX => &[".codex/auth.json"],
        HarnessId::GEMINI => &[
            ".gemini/google_accounts.json",
            ".gemini/oauth_creds.json",
            ".gemini/settings.json",
        ],
        HarnessId::GROK => &[".grok/auth.json", ".grok/config.toml"],
        HarnessId::OPENCODE => &[
            ".config/opencode/auth.json",
            ".local/share/opencode/auth.json",
        ],
        HarnessId::PI => &[".pi/agent/auth.json"],
        HarnessId::SUPERCODE => &[
            ".config/supercode/config.toml",
            ".config/supercode/credentials.toml",
        ],
        _ => &[],
    }
}

fn copy_probe_file(source_home: &Path, probe_home: &Path, relative: &str) -> std::io::Result<()> {
    let source = source_home.join(relative);
    if !source.is_file() {
        return Ok(());
    }
    let destination = probe_home.join(relative);
    if let Some(parent) = destination.parent() {
        std::fs::create_dir_all(parent)?;
        set_private_dir_permissions(parent)?;
    }
    std::fs::copy(source, &destination)?;
    set_private_file_permissions(&destination)
}

fn configure_isolated_probe_auth(harness: &str, probe_home: &Path) -> std::io::Result<()> {
    if harness != HarnessId::GEMINI {
        return Ok(());
    }
    let oauth = probe_home.join(".gemini/oauth_creds.json");
    if !oauth.is_file() {
        return Ok(());
    }
    let settings_path = probe_home.join(".gemini/settings.json");
    let mut settings = std::fs::read_to_string(&settings_path)
        .ok()
        .and_then(|raw| serde_json::from_str::<Value>(&raw).ok())
        .unwrap_or_else(|| json!({}));
    settings["security"]["auth"]["selectedType"] = Value::String("oauth-personal".into());
    std::fs::write(
        &settings_path,
        serde_json::to_vec_pretty(&settings).map_err(std::io::Error::other)?,
    )?;
    set_private_file_permissions(&settings_path)
}

#[cfg(unix)]
fn set_private_dir_permissions(path: &Path) -> std::io::Result<()> {
    use std::os::unix::fs::PermissionsExt;
    std::fs::set_permissions(path, std::fs::Permissions::from_mode(0o700))
}

#[cfg(not(unix))]
fn set_private_dir_permissions(_path: &Path) -> std::io::Result<()> {
    Ok(())
}

#[cfg(unix)]
fn set_private_file_permissions(path: &Path) -> std::io::Result<()> {
    use std::os::unix::fs::PermissionsExt;
    std::fs::set_permissions(path, std::fs::Permissions::from_mode(0o600))
}

#[cfg(not(unix))]
fn set_private_file_permissions(_path: &Path) -> std::io::Result<()> {
    Ok(())
}

fn find_executable(program: &str) -> Option<PathBuf> {
    let candidate = PathBuf::from(program);
    if candidate.components().count() > 1 {
        return candidate.is_file().then_some(candidate);
    }
    let path = std::env::var_os("PATH")?;
    for directory in std::env::split_paths(&path) {
        let candidate = directory.join(program);
        if candidate.is_file() {
            return std::fs::canonicalize(&candidate).ok().or(Some(candidate));
        }
        #[cfg(windows)]
        {
            for extension in ["exe", "cmd", "bat"] {
                let candidate = directory.join(format!("{program}.{extension}"));
                if candidate.is_file() {
                    return std::fs::canonicalize(&candidate).ok().or(Some(candidate));
                }
            }
        }
    }
    None
}

async fn executable_version(executable: &Path) -> Option<String> {
    let mut command = tokio::process::Command::new(executable);
    command
        .arg("--version")
        .stdin(std::process::Stdio::null())
        .stdout(std::process::Stdio::piped())
        .stderr(std::process::Stdio::piped())
        .kill_on_drop(true);
    let output = tokio::time::timeout(Duration::from_secs(3), command.output())
        .await
        .ok()?
        .ok()?;
    let stdout = String::from_utf8_lossy(&output.stdout);
    let stderr = String::from_utf8_lossy(&output.stderr);
    stdout
        .lines()
        .chain(stderr.lines())
        .map(str::trim)
        .find(|line| !line.is_empty())
        .map(|line| truncate_text(line, 200))
}

fn auth_evidence(harness: &str) -> bool {
    let env_names: &[&str] = match harness {
        HarnessId::CLAUDE_CODE => &["ANTHROPIC_API_KEY", "CLAUDE_CODE_OAUTH_TOKEN"],
        HarnessId::CODEX => &["OPENAI_API_KEY"],
        HarnessId::OPENCODE => &["ANTHROPIC_API_KEY", "OPENAI_API_KEY", "OPENROUTER_API_KEY"],
        HarnessId::PI => &["ANTHROPIC_API_KEY", "OPENAI_API_KEY", "OPENROUTER_API_KEY"],
        HarnessId::GROK => &["XAI_API_KEY", "GROK_API_KEY"],
        HarnessId::GEMINI => &["GEMINI_API_KEY", "GOOGLE_API_KEY"],
        HarnessId::SUPERCODE => &["OPENROUTER_API_KEY"],
        _ => &[],
    };
    if env_names
        .iter()
        .any(|name| std::env::var_os(name).is_some_and(|value| !value.is_empty()))
    {
        return true;
    }
    let Some(home) = std::env::var_os("HOME").map(PathBuf::from) else {
        return false;
    };
    let files: Vec<PathBuf> = match harness {
        HarnessId::CLAUDE_CODE => vec![home.join(".claude/.credentials.json")],
        HarnessId::CODEX => vec![home.join(".codex/auth.json")],
        HarnessId::OPENCODE => vec![
            home.join(".local/share/opencode/auth.json"),
            home.join(".config/opencode/auth.json"),
        ],
        HarnessId::PI => vec![home.join(".pi/agent/auth.json")],
        HarnessId::GROK => vec![home.join(".grok/auth.json")],
        HarnessId::GEMINI => vec![
            home.join(".gemini/oauth_creds.json"),
            home.join(".gemini/google_accounts.json"),
        ],
        HarnessId::SUPERCODE => vec![home.join(".config/supercode/credentials.toml")],
        _ => Vec::new(),
    };
    if files.into_iter().any(|path| {
        std::fs::metadata(path)
            .map(|metadata| metadata.is_file() && metadata.len() > 2)
            .unwrap_or(false)
    }) {
        return true;
    }
    // macOS keeps Claude Code's OAuth login in the Keychain, so
    // `.claude/.credentials.json` never exists there and the file probe above
    // reports a signed-in install as unauthenticated forever. A completed
    // login also writes an `oauthAccount` record into `~/.claude.json` on
    // every platform — file-based, prompt-free evidence (querying the
    // Keychain itself from an unsigned daemon can raise a UI prompt).
    if harness == HarnessId::CLAUDE_CODE {
        return std::fs::read_to_string(home.join(".claude.json"))
            .map(|text| text.contains("\"oauthAccount\""))
            .unwrap_or(false);
    }
    false
}

fn looks_like_auth_error(message: &str) -> bool {
    let message = message.to_ascii_lowercase();
    [
        "auth",
        "login",
        "sign in",
        "sign-in",
        "credential",
        "unauthorized",
        "forbidden",
        "token",
    ]
    .iter()
    .any(|needle| message.contains(needle))
}

fn unavailable_capabilities() -> crate::RuntimeCapabilities {
    crate::RuntimeCapabilities {
        start_session: false,
        resume_session: false,
        attach_existing_process: false,
        send_input: false,
        stream_events: false,
        interrupt: false,
        respond_to_requests: false,
    }
}

fn truncate_text(text: &str, max_chars: usize) -> String {
    let mut chars = text.chars();
    let truncated = chars.by_ref().take(max_chars).collect::<String>();
    if chars.next().is_some() {
        format!("{truncated}…")
    } else {
        truncated
    }
}

fn error_message(error: ServiceError) -> String {
    match error {
        ServiceError::InvalidParams(message)
        | ServiceError::Operation(message)
        | ServiceError::UnsupportedAction(message) => message,
        ServiceError::MethodNotFound => "runtime adapter is not available".into(),
        ServiceError::Sdk(error) => error.to_string(),
    }
}

#[derive(Debug)]
enum ServiceError {
    InvalidParams(String),
    MethodNotFound,
    UnsupportedAction(String),
    Operation(String),
    Sdk(SdkError),
}

fn sdk_error(operation: SdkOperation, error: ServiceError) -> SdkError {
    match error {
        ServiceError::InvalidParams(message) => {
            SdkError::new(SdkErrorCode::InvalidArgument, operation, message)
        }
        ServiceError::MethodNotFound | ServiceError::UnsupportedAction(_) => {
            SdkError::unsupported(operation)
        }
        ServiceError::Operation(message) => {
            let code = if message.contains("already in progress") {
                SdkErrorCode::Busy
            } else if message.contains("not supported by this runtime") {
                SdkErrorCode::UnsupportedAction
            } else if message.contains("unknown runtime connection") {
                SdkErrorCode::NotFound
            } else {
                SdkErrorCode::Execution
            };
            SdkError::new(code, operation, message)
        }
        ServiceError::Sdk(error) => error,
    }
}

fn sdk_rpc_error(id: Value, error: &SdkError) -> Value {
    let error_code = error.code();
    let code = match error_code {
        SdkErrorCode::Unauthenticated => -32030,
        SdkErrorCode::Unauthorized => -32031,
        SdkErrorCode::ControllerRequired => -32032,
        SdkErrorCode::LeaseExpired => -32033,
        SdkErrorCode::InvalidArgument => -32602,
        SdkErrorCode::NotFound => -32004,
        SdkErrorCode::Busy => -32000,
        SdkErrorCode::UnsupportedAction => -32020,
        SdkErrorCode::Execution => -32002,
        SdkErrorCode::Transport => -32003,
    };
    json!({
        "jsonrpc": "2.0",
        "id": id,
        "error": {
            "code": code,
            "name": error_code,
            "operation": error.operation(),
            "message": error.to_string(),
        },
    })
}

fn decode<T: for<'de> Deserialize<'de>>(value: Value) -> std::result::Result<T, ServiceError> {
    serde_json::from_value(value).map_err(|error| ServiceError::InvalidParams(error.to_string()))
}

fn operation(error: impl Into<crate::Error>) -> ServiceError {
    let error = error.into();
    match error {
        crate::Error::Sdk(error) => ServiceError::Sdk(error),
        error => ServiceError::Operation(error.to_string()),
    }
}

fn rpc_error(id: Value, code: i64, message: &str) -> Value {
    json!({
        "jsonrpc": "2.0",
        "id": id,
        "error": {"code": code, "message": message},
    })
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::{HarnessEvent, HarnessId, RuntimeEndpoint, RuntimeHandle, StorageLocator};
    use async_trait::async_trait;
    use std::io::Write;
    use std::path::PathBuf;
    use std::time::Instant;

    struct EndingRuntime {
        handle: RuntimeHandle,
        event: Option<HarnessEvent>,
    }

    #[async_trait]
    impl RuntimeConnection for EndingRuntime {
        fn handle(&self) -> &RuntimeHandle {
            &self.handle
        }

        async fn send_input(&mut self, _input: RuntimeInput) -> crate::Result<Option<String>> {
            unreachable!("ending runtime does not accept input")
        }

        async fn next_event(&mut self) -> crate::Result<Option<HarnessEvent>> {
            Ok(self.event.take())
        }

        async fn interrupt(&mut self) -> crate::Result<()> {
            Ok(())
        }

        async fn respond(&mut self, _request_id: Value, _response: Value) -> crate::Result<()> {
            Ok(())
        }

        async fn close(&mut self) -> crate::Result<()> {
            Ok(())
        }
    }

    fn ending_runtime(event: Option<HarnessEvent>) -> Box<dyn RuntimeConnection> {
        Box::new(EndingRuntime {
            handle: RuntimeHandle {
                harness: HarnessId::from(HarnessId::CLAUDE_CODE),
                runtime_id: "ending-session".into(),
                endpoint: RuntimeEndpoint::LocalProcess {
                    pid: None,
                    command: vec!["ending-runtime".into()],
                    protocol: "test".into(),
                },
            },
            event,
        })
    }

    fn request(id: u64, method: &str, params: Value) -> Value {
        json!({"jsonrpc": "2.0", "id": id, "method": method, "params": params})
    }

    fn pi_locator() -> SessionLocator {
        SessionLocator {
            harness: HarnessId::from(HarnessId::PI),
            session_id: "1e6f2a3b-0000-4000-8000-000000000001".into(),
            storage: StorageLocator::File {
                path: PathBuf::from(env!("CARGO_MANIFEST_DIR"))
                    .join("tests/fixtures/pi_session.jsonl"),
            },
        }
    }

    fn opencode_locator() -> SessionLocator {
        let session_id = "ses_fixtureAAAAAAAAAAAAAAA1";
        SessionLocator {
            harness: HarnessId::from(HarnessId::OPENCODE),
            session_id: session_id.into(),
            storage: StorageLocator::Sqlite {
                path: PathBuf::from(env!("CARGO_MANIFEST_DIR"))
                    .join("tests/fixtures/opencode_fixture/opencode.db"),
                selector: session_id.into(),
            },
        }
    }

    fn grok_locator() -> SessionLocator {
        SessionLocator {
            harness: HarnessId::from(HarnessId::GROK),
            session_id: "73c09283-4b33-41fa-90f1-0bcb0f7be523".into(),
            storage: StorageLocator::File {
                path: PathBuf::from(env!("CARGO_MANIFEST_DIR"))
                    .join("tests/fixtures/grok_session/chat_history.jsonl"),
            },
        }
    }

    #[test]
    fn capabilities_are_explicit_and_versioned() {
        let mut service = HarnessSessionService::new();
        let response = service.handle(request(1, "harness.v1.capabilities", json!({})));
        assert_eq!(response["result"]["version"], HARNESS_SERVICE_VERSION);
        assert_eq!(
            response["result"]["sdk"]["schema_version"],
            crate::SDK_SCHEMA_VERSION
        );
        assert_eq!(
            response["result"]["sdk"]["operations"]
                .as_array()
                .unwrap()
                .len(),
            SdkOperation::ALL.len()
        );
        assert_eq!(response["result"]["harnesses"].as_array().unwrap().len(), 8);
        assert!(response["result"]["harnesses"]
            .as_array()
            .unwrap()
            .iter()
            .any(|harness| harness == HarnessId::GROK));
        assert!(response["result"]["harnesses"]
            .as_array()
            .unwrap()
            .iter()
            .any(|harness| harness == HarnessId::GOOSE));
    }

    #[test]
    fn handshake_health_uses_protocol_liveness_not_stderr_severity() {
        let noisy_stderr = crate::HarnessEvent {
            sequence: None,
            kind: "transport_stderr".into(),
            payload: json!({"line": "ERROR optional worker AuthorizationRequired"}),
        };
        assert_eq!(handshake_event_failure(&noisy_stderr), None);

        let closed = crate::HarnessEvent {
            sequence: None,
            kind: "transport_closed".into(),
            payload: json!({}),
        };
        assert!(handshake_event_failure(&closed).is_some());
    }

    #[tokio::test]
    async fn runtime_eof_is_notified_and_removed_for_raw_and_explicit_close() {
        let mut service = HarnessSessionService::new();
        service
            .runtimes
            .insert("raw-eof".into(), ending_runtime(None));
        service.runtimes.insert(
            "explicit-close".into(),
            ending_runtime(Some(HarnessEvent {
                sequence: None,
                kind: "transport_closed".into(),
                payload: json!({"message": "native transport exited"}),
            })),
        );

        let notifications = service.poll_runtimes().await;

        assert_eq!(notifications.len(), 2);
        assert!(notifications
            .iter()
            .all(|notification| { notification["params"]["event"]["kind"] == "transport_closed" }));
        assert!(notifications.iter().all(|notification| {
            notification["params"]["session_id"] == "ending-session"
                && notification["params"]["connection"].is_string()
        }));
        let mut sequences = notifications
            .iter()
            .filter_map(|notification| notification["params"]["sequence"].as_u64())
            .collect::<Vec<_>>();
        sequences.sort_unstable();
        assert_eq!(sequences, vec![1, 2]);
        assert!(service.runtimes.is_empty());
    }

    #[tokio::test]
    async fn sdk_facade_returns_named_unsupported_actions() {
        let mut service = HarnessSessionService::new();
        let error = service
            .execute(SdkRequest {
                operation: SdkOperation::Steer,
                params: json!({"connection": "runtime-1", "text": "go left"}),
            })
            .await
            .unwrap_err();
        assert_eq!(error.code(), SdkErrorCode::UnsupportedAction);
        assert_eq!(error.operation(), Some(SdkOperation::Steer));

        let response = service
            .handle_async(request(
                7,
                "harness.v1.runtimes.steer",
                json!({"connection": "runtime-1", "text": "go left"}),
            ))
            .await;
        assert_eq!(response["error"]["name"], "unsupported_action");
        assert_eq!(response["error"]["operation"], "steer");
    }

    #[test]
    fn support_report_and_grok_default_binding_share_the_registry() {
        let mut service = HarnessSessionService::new();
        let response = service.handle(request(1, "harness.v1.support.report", json!({})));
        assert_eq!(response["result"]["schema"], crate::SUPPORT_REGISTRY_SCHEMA);
        let params = RuntimeBackendParams {
            harness: HarnessId::from(HarnessId::GROK),
            protocol: None,
            launch: None,
            base_url: None,
            policy: RuntimePolicy::Default,
        };
        let backend = match runtime_backend(&params) {
            Ok(backend) => backend,
            Err(_) => panic!("Grok should bind through its registered ACP launch"),
        };
        assert_eq!(backend.harness().as_str(), HarnessId::GROK);
        assert!(backend.capabilities().start_session);
        let registered = harness_support_registry()
            .harnesses
            .into_iter()
            .find(|harness| harness.id.as_str() == HarnessId::GROK)
            .and_then(|harness| harness.runtime.default_launch)
            .unwrap();
        assert!(!registered
            .arguments
            .iter()
            .any(|argument| argument == "--always-approve"));
        assert!(runtime_launch(&params).is_none());

        let yolo = RuntimeBackendParams {
            policy: RuntimePolicy::Yolo,
            ..params
        };
        assert!(runtime_launch(&yolo)
            .unwrap()
            .arguments
            .iter()
            .any(|argument| argument == "--always-approve"));

        let mismatched_protocol = RuntimeBackendParams {
            harness: HarnessId::from(HarnessId::CLAUDE_CODE),
            protocol: Some("acp".into()),
            launch: None,
            base_url: None,
            policy: RuntimePolicy::Default,
        };
        assert!(runtime_backend(&mismatched_protocol).is_err());
    }

    #[test]
    fn load_follow_and_unfollow_share_the_same_locator() {
        let mut service = HarnessSessionService::new();
        let locator = pi_locator();
        let loaded = service.handle(request(
            1,
            "harness.v1.sessions.load",
            json!({"locator": locator}),
        ));
        assert_eq!(
            loaded["result"]["session"]["session_id"],
            locator.session_id
        );

        let followed = service.handle(request(
            2,
            "harness.v1.sessions.follow",
            json!({"locator": locator}),
        ));
        assert_eq!(followed["result"]["subscription"], "sub-1");
        assert_eq!(followed["result"]["initial"]["type"], "session_snapshot");
        assert!(service.poll().is_empty());

        let unfollowed = service.handle(request(
            3,
            "harness.v1.sessions.unfollow",
            json!({"subscription": "sub-1"}),
        ));
        assert_eq!(unfollowed["result"]["removed"], true);
    }

    #[test]
    fn bounded_read_view_excludes_subagents_and_keeps_only_the_tail() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-bounded-view-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        let path = temp.join("parent.jsonl");
        let subagents = temp.join("parent/subagents");
        std::fs::create_dir_all(&subagents).unwrap();
        let long_last = "x".repeat(300);
        let parent_records = [
            json!({"type":"user","uuid":"u1","parentUuid":null,"message":{"role":"user","content":"first"}}),
            json!({"type":"assistant","uuid":"a1","parentUuid":"u1","message":{"role":"assistant","content":[{"type":"text","text":"middle"}]}}),
            json!({"type":"user","uuid":"u2","parentUuid":"a1","message":{"role":"user","content":long_last}}),
        ];
        std::fs::write(
            &path,
            format!(
                "{}\n",
                parent_records
                    .iter()
                    .map(Value::to_string)
                    .collect::<Vec<_>>()
                    .join("\n")
            ),
        )
        .unwrap();
        std::fs::write(
            subagents.join("agent-child.jsonl"),
            concat!(
                r#"{"type":"user","uuid":"cu","parentUuid":null,"agentId":"child","message":{"role":"user","content":"child work"}}"#,
                "\n",
            ),
        )
        .unwrap();
        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CLAUDE_CODE),
            session_id: "parent".into(),
            storage: StorageLocator::File { path },
        };
        let mut service = HarnessSessionService::new();

        let complete = service.handle(request(
            1,
            "harness.v1.sessions.load",
            json!({"locator": locator}),
        ));
        assert_eq!(
            complete["result"]["session"]["subagents"]
                .as_array()
                .unwrap()
                .len(),
            1
        );

        let bounded = service.handle(request(
            2,
            "harness.v1.sessions.load",
            json!({
                "locator": locator,
                "view": {
                    "tail_messages": 1,
                    "max_message_chars": 256,
                    "include_subagents": false
                },
            }),
        ));
        let session = &bounded["result"]["session"];
        assert!(session["subagents"].as_array().unwrap().is_empty());
        assert_eq!(session["messages"].as_array().unwrap().len(), 1);
        assert_eq!(
            session["messages"][0]["content"],
            format!("{}\n…", "x".repeat(256))
        );

        let followed = service.handle(request(
            3,
            "harness.v1.sessions.follow",
            json!({
                "locator": locator,
                "view": {
                    "tail_messages": 1,
                    "max_message_chars": 256,
                    "include_subagents": false
                },
            }),
        ));
        let initial = &followed["result"]["initial"]["session"];
        assert!(initial["subagents"].as_array().unwrap().is_empty());
        assert_eq!(initial["messages"].as_array().unwrap().len(), 1);

        let _ = std::fs::remove_dir_all(&temp);
    }

    #[test]
    fn forty_megabyte_display_load_is_bounded_and_prompt() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-large-display-view-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        std::fs::create_dir_all(&temp).unwrap();
        let path = temp.join("rollout.jsonl");
        let mut file = std::io::BufWriter::new(std::fs::File::create(&path).unwrap());
        writeln!(
            file,
            r#"{{"timestamp":"2026-01-01T00:00:00Z","type":"session_meta","payload":{{"id":"large-display","cwd":"/tmp"}}}}"#
        )
        .unwrap();
        let padding = "x".repeat(80 * 1024);
        for index in 0..512 {
            let marker = if index == 0 {
                "OLDEST-SHOULD-NOT-LOAD"
            } else if index == 511 {
                "LATEST-MUST-LOAD"
            } else {
                "bulk"
            };
            writeln!(
                file,
                "{}",
                json!({
                    "timestamp": "2026-01-01T00:00:01Z",
                    "type": "response_item",
                    "payload": {
                        "type": "message",
                        "role": "assistant",
                        "content": [{"type": "output_text", "text": format!("{marker}:{padding}")}],
                    },
                })
            )
            .unwrap();
        }
        file.flush().unwrap();
        drop(file);
        assert!(std::fs::metadata(&path).unwrap().len() >= 40 * 1024 * 1024);

        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CODEX),
            session_id: "large-display".into(),
            storage: StorageLocator::File { path },
        };
        let started = Instant::now();
        let response = HarnessSessionService::new().handle(request(
            1,
            "harness.v1.sessions.load",
            json!({
                "locator": locator,
                "view": {
                    "tail_messages": 500,
                    "max_message_chars": 1024,
                    "include_subagents": false,
                    "display_history": true,
                },
            }),
        ));
        let elapsed = started.elapsed();
        let wire = response.to_string();
        eprintln!(
            "bounded 40 MiB display load: {elapsed:?}, {} response bytes",
            wire.len()
        );
        assert!(response.get("error").is_none(), "{response:#}");
        assert!(wire.contains("LATEST-MUST-LOAD"));
        assert!(!wire.contains("OLDEST-SHOULD-NOT-LOAD"));
        assert!(
            wire.len() < 2 * 1024 * 1024,
            "bounded wire was {} bytes",
            wire.len()
        );
        assert!(
            elapsed.as_secs_f64() < 3.0,
            "bounded 40 MiB load took {elapsed:?}"
        );

        let _ = std::fs::remove_dir_all(&temp);
    }

    #[test]
    fn forty_megabyte_goose_store_display_load_reads_only_the_tail() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-large-goose-view-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        std::fs::create_dir_all(&temp).unwrap();
        let path = temp.join("sessions.db");
        let connection = rusqlite::Connection::open(&path).unwrap();
        connection
            .execute_batch(
                "CREATE TABLE sessions (
                    id TEXT PRIMARY KEY, name TEXT NOT NULL, working_dir TEXT NOT NULL,
                    created_at TEXT NOT NULL, updated_at TEXT NOT NULL,
                    session_type TEXT NOT NULL, extension_data TEXT,
                    goose_mode TEXT NOT NULL, provider_name TEXT, model_config_json TEXT,
                    archived_at TEXT
                 );
                 CREATE TABLE messages (
                    id INTEGER PRIMARY KEY, session_id TEXT NOT NULL, message_id TEXT,
                    role TEXT NOT NULL, content_json TEXT NOT NULL,
                    created_timestamp INTEGER NOT NULL, metadata_json TEXT
                 );",
            )
            .unwrap();
        connection
            .execute(
                "INSERT INTO sessions VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, NULL)",
                rusqlite::params![
                    "goose-large",
                    "Large Goose session",
                    "/tmp",
                    "2026-01-01 00:00:00",
                    "2026-01-01 00:00:02",
                    "user",
                    "{}",
                    "auto",
                    "anthropic",
                    r#"{"model_name":"claude-sonnet"}"#,
                ],
            )
            .unwrap();
        let old_content = serde_json::to_string(&vec![json!({
            "type": "text",
            "text": format!("OLDEST-SHOULD-NOT-LOAD:{}", "x".repeat(40 * 1024 * 1024)),
        })])
        .unwrap();
        connection
            .execute(
                "INSERT INTO messages VALUES (1, ?1, 'old', 'user', ?2, 1, '{}')",
                rusqlite::params!["goose-large", old_content],
            )
            .unwrap();
        connection
            .execute(
                "INSERT INTO messages VALUES (2, ?1, 'new', 'assistant', ?2, 2, '{}')",
                rusqlite::params![
                    "goose-large",
                    r#"[{"type":"text","text":"LATEST-MUST-LOAD"}]"#
                ],
            )
            .unwrap();
        drop(connection);
        assert!(std::fs::metadata(&path).unwrap().len() >= 40 * 1024 * 1024);

        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::GOOSE),
            session_id: "goose-large".into(),
            storage: StorageLocator::Sqlite {
                path,
                selector: "goose-large".into(),
            },
        };
        let started = Instant::now();
        let response = HarnessSessionService::new().handle(request(
            1,
            "harness.v1.sessions.load",
            json!({
                "locator": locator,
                "view": {
                    "tail_messages": 1,
                    "max_message_chars": 1024,
                    "include_subagents": false,
                    "display_history": true,
                },
            }),
        ));
        let elapsed = started.elapsed();
        let wire = response.to_string();
        eprintln!(
            "bounded 40 MiB Goose display load: {elapsed:?}, {} response bytes",
            wire.len()
        );
        assert!(response.get("error").is_none(), "{response:#}");
        assert!(wire.contains("LATEST-MUST-LOAD"));
        assert!(!wire.contains("OLDEST-SHOULD-NOT-LOAD"));
        assert!(
            wire.len() < 64 * 1024,
            "bounded wire was {} bytes",
            wire.len()
        );
        assert!(
            elapsed.as_secs_f64() < 1.0,
            "bounded Goose load took {elapsed:?}"
        );

        let _ = std::fs::remove_dir_all(&temp);
    }

    #[test]
    fn display_view_keeps_codex_assistant_history_across_compaction() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-codex-display-view-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        std::fs::create_dir_all(&temp).unwrap();
        let path = temp.join("rollout.jsonl");
        std::fs::write(
            &path,
            concat!(
                r#"{"timestamp":"2026-01-01T00:00:00Z","type":"session_meta","payload":{"id":"codex-display","cwd":"/tmp"}}"#,
                "\n",
                r#"{"timestamp":"2026-01-01T00:00:01Z","type":"response_item","payload":{"type":"message","role":"user","content":[{"type":"input_text","text":"old prompt"}]}}"#,
                "\n",
                r#"{"timestamp":"2026-01-01T00:00:02Z","type":"response_item","payload":{"type":"message","role":"assistant","content":[{"type":"output_text","text":"old answer"}]}}"#,
                "\n",
                r#"{"timestamp":"2026-01-01T00:00:03Z","type":"compacted","payload":{"replacement_history":[{"type":"message","role":"user","content":[{"type":"input_text","text":"old prompt"}]},{"type":"compaction","encrypted_content":"opaque"}]}}"#,
                "\n",
                r#"{"timestamp":"2026-01-01T00:00:04Z","type":"response_item","payload":{"type":"message","role":"user","content":[{"type":"input_text","text":"new prompt"}]}}"#,
                "\n",
                r#"{"timestamp":"2026-01-01T00:00:05Z","type":"response_item","payload":{"type":"message","role":"assistant","content":[{"type":"output_text","text":"new answer"}]}}"#,
                "\n",
            ),
        )
        .unwrap();
        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CODEX),
            session_id: "codex-display".into(),
            storage: StorageLocator::File { path },
        };
        let mut service = HarnessSessionService::new();

        let continuation = service.handle(request(
            1,
            "harness.v1.sessions.load",
            json!({"locator": locator}),
        ));
        let continuation_text = continuation["result"]["session"]["messages"].to_string();
        assert!(!continuation_text.contains("old answer"));

        let display = service.handle(request(
            2,
            "harness.v1.sessions.load",
            json!({
                "locator": locator,
                "view": {
                    "tail_messages": 10,
                    "include_subagents": false,
                    "display_history": true,
                },
            }),
        ));
        let display_text = display["result"]["session"]["messages"].to_string();
        assert!(display_text.contains("old prompt"));
        assert!(display_text.contains("old answer"));
        assert!(display_text.contains("new prompt"));
        assert!(display_text.contains("new answer"));

        let _ = std::fs::remove_dir_all(&temp);
    }

    #[test]
    fn load_supports_bounded_windows_and_media_metadata() {
        let mut service = HarnessSessionService::new();
        let locator = pi_locator();
        let bounded = service.handle(request(
            1,
            "harness.v1.sessions.load",
            json!({
                "locator": locator,
                "options": {
                    "include_subagents": false,
                    "message_limit": 2,
                    "message_offset": 1
                }
            }),
        ));
        assert_eq!(bounded["result"]["window"]["offset"], 1);
        assert_eq!(bounded["result"]["window"]["returned"], 2);
        assert!(bounded["result"]["summary"]["first_message"].is_object());
        assert!(bounded["result"]["summary"]["last_message"].is_object());
        assert_eq!(
            bounded["result"]["session"]["messages"]
                .as_array()
                .unwrap()
                .len(),
            2
        );
        assert!(bounded["result"]["session"]["subagents"]
            .as_array()
            .unwrap()
            .is_empty());

        let tail = service.handle(request(
            2,
            "harness.v1.sessions.load",
            json!({"locator": locator, "options": {"message_tail": 1}}),
        ));
        assert_eq!(tail["result"]["window"]["returned"], 1);
        assert_eq!(tail["result"]["window"]["has_more"], true);
        assert_eq!(tail["result"]["window"]["has_older"], true);
        assert!(tail["result"]["window"]["older_items"].as_u64().unwrap() > 0);
        assert!(tail["result"]["summary"]["first_message"].is_object());

        let metadata_only = service.handle(request(
            3,
            "harness.v1.sessions.load",
            json!({"locator": locator, "options": {"inline_media": "metadata"}}),
        ));
        assert!(metadata_only["result"]["session"]
            .to_string()
            .contains("media_reference"));
        assert!(!metadata_only["result"]["session"]
            .to_string()
            .contains("data:image/"));
    }

    #[test]
    fn import_translate_branch_and_handoff_use_typed_artifacts() {
        let mut service = HarnessSessionService::new();
        let locator = pi_locator();
        let translated = service.handle(request(
            1,
            "harness.v1.sessions.translate",
            json!({"locator": locator, "target_harness": "grok"}),
        ));
        assert_eq!(translated["result"]["artifact"]["source_harness"], "pi");
        assert_eq!(translated["result"]["artifact"]["target_harness"], "grok");
        assert!(translated["result"]["artifact"]["content"]
            .as_str()
            .is_some_and(|content| !content.is_empty()));

        for target in ["opencode", "open-code"] {
            let opencode = service.handle(request(
                6,
                "harness.v1.sessions.translate",
                json!({"locator": locator, "target_harness": target}),
            ));
            assert_eq!(opencode["result"]["artifact"]["target_harness"], "opencode");
        }
        let goose = service.handle(request(
            7,
            "harness.v1.sessions.translate",
            json!({"locator": locator, "target_harness": "goose"}),
        ));
        assert_eq!(goose["result"]["artifact"]["target_harness"], "goose");
        assert!(serde_json::from_str::<Value>(
            goose["result"]["artifact"]["content"].as_str().unwrap()
        )
        .unwrap()["conversation"]
            .is_array());

        let imported = service.handle(request(
            2,
            "harness.v1.sessions.import",
            json!({
                "source_harness": "grok",
                "content": translated["result"]["artifact"]["content"],
            }),
        ));
        assert_eq!(imported["result"]["session"]["source"], "grok");

        let branched = service.handle(request(
            3,
            "harness.v1.sessions.branch",
            json!({"locator": locator, "target_harness": "codex"}),
        ));
        assert_eq!(branched["result"]["parent"]["harness"], "pi");
        assert!(branched["result"]["bootstrap_prompt"]
            .as_str()
            .unwrap()
            .contains("frozen parent transcript"));
        assert_eq!(branched["result"]["artifact"]["target_harness"], "codex");

        let handoff = service.handle(request(
            4,
            "harness.v1.sessions.handoff",
            json!({"locator": locator, "target_harness": "pi", "cwd": "/tmp/project"}),
        ));
        assert_eq!(handoff["result"]["launch"]["program"], "pi");
        assert_eq!(handoff["result"]["launch"]["cwd"], "/tmp/project");
        assert_eq!(handoff["result"]["requires_materialization"], true);

        let goose_handoff = service.handle(request(
            8,
            "harness.v1.sessions.handoff",
            json!({"locator": locator, "target_harness": "goose", "cwd": "/tmp/project"}),
        ));
        assert_eq!(goose_handoff["result"]["launch"]["program"], "goose");
        assert_eq!(
            goose_handoff["result"]["materialize"]["arguments"],
            json!(["session", "import", "{artifact_path}"])
        );

        let resumed = service.handle(request(
            5,
            "harness.v1.sessions.resume_instructions",
            json!({"locator": locator, "cwd": "/tmp/project", "policy": "yolo"}),
        ));
        assert_eq!(resumed["result"]["launch"]["program"], "pi");
        assert_eq!(resumed["result"]["launch"]["arguments"][0], "--approve");
    }

    #[test]
    fn reduce_persists_and_reloads_a_byte_exact_reversible_bundle() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-service-reduce-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        let source_path = temp.join("source.jsonl");
        let store_root = temp.join("store");
        std::fs::create_dir_all(&temp).unwrap();

        let mut records = vec![json!({
            "timestamp": "2026-01-01T00:00:00Z",
            "type": "session_meta",
            "payload": {"id": "codex-reduce", "cwd": "/tmp/project"},
        })];
        for turn in 0..16 {
            records.push(json!({
                "timestamp": format!("2026-01-01T00:00:{:02}Z", turn * 2 + 1),
                "type": "response_item",
                "payload": {
                    "type": "message",
                    "role": "user",
                    "content": [{
                        "type": "input_text",
                        "text": format!("request {turn}: {}", "context ".repeat(80)),
                    }],
                },
            }));
            records.push(json!({
                "timestamp": format!("2026-01-01T00:00:{:02}Z", turn * 2 + 2),
                "type": "response_item",
                "payload": {
                    "type": "message",
                    "role": "assistant",
                    "content": [{
                        "type": "output_text",
                        "text": format!("answer {turn}: {}", "implementation detail ".repeat(80)),
                    }],
                },
            }));
        }
        let source = format!(
            "{}\n",
            records
                .iter()
                .map(Value::to_string)
                .collect::<Vec<_>>()
                .join("\n")
        );
        std::fs::write(&source_path, &source).unwrap();
        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CODEX),
            session_id: "codex-reduce".into(),
            storage: StorageLocator::File {
                path: source_path.clone(),
            },
        };
        let original = load_session(&locator).unwrap();
        let mut service =
            HarnessSessionService::new().with_reduction_store_root(store_root.clone());

        let response = service.handle(request(
            1,
            "harness.v1.sessions.reduce",
            json!({
                "locator": locator,
                "target_harness": "claude-code",
                "keep_last": 4,
            }),
        ));
        assert!(response.get("error").is_none(), "{response:#}");
        let receipt = &response["result"]["receipt"];
        assert_eq!(receipt["source_harness"], "codex");
        assert_eq!(receipt["target_harness"], "claude-code");
        assert_eq!(receipt["verified"], true);
        assert_eq!(receipt["reversible"], true);
        assert!(receipt["reductions"].as_u64().unwrap() > 0);
        assert!(
            receipt["source_tokens"].as_u64().unwrap()
                > receipt["reduced_tokens"].as_u64().unwrap()
        );
        assert!(receipt["ratio"].as_f64().unwrap() > 1.0);
        assert!(response["result"]["bootstrap_prompt"]
            .as_str()
            .unwrap()
            .contains("Do not guess hidden content"));

        let rescue_id = receipt["id"].as_str().unwrap();
        let store = crate::SessionStore::open(&store_root).unwrap();
        let sidecar =
            Session::from_sidecar_str(&store.load_sidecar(rescue_id).unwrap().unwrap()).unwrap();
        let log = store.load_reduction_log(rescue_id).unwrap().unwrap();
        let persisted_view = parse_messages_jsonl(&store.load(rescue_id).unwrap()).unwrap();
        let policy = reduce::ReductionPolicy {
            clear_turns_older_than: Some(4),
            ..Default::default()
        };
        let (restamped_view, reapplied_log) =
            reduce::project_messages(&sidecar.messages, &policy, &log);
        assert_eq!(
            messages_jsonl(&persisted_view).unwrap(),
            messages_jsonl(&restamped_view).unwrap()
        );
        assert_eq!(reapplied_log, log);
        reduce::verify_log(&log, &sidecar).unwrap();
        assert_eq!(
            reduce::invert(&restamped_view, &log, &sidecar).unwrap(),
            original.messages
        );
        assert_eq!(std::fs::read_to_string(&source_path).unwrap(), source);

        std::fs::remove_dir_all(temp).ok();
    }

    #[test]
    fn read_surfaces_view_a_severed_claude_graph_while_transfer_still_refuses_it() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-severed-view-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        std::fs::create_dir_all(&temp).unwrap();
        let path = temp.join("severed.jsonl");
        // A live record whose parent was pruned — what a compacted or
        // resumed-across-files Claude Code session looks like on disk.
        std::fs::write(
            &path,
            concat!(
                r#"{"type":"user","uuid":"orphan-u","parentUuid":null,"message":{"role":"user","content":"stranded prompt"}}"#,
                "\n",
                r#"{"type":"assistant","uuid":"live-a","parentUuid":"pruned","message":{"id":"m","role":"assistant","content":[{"type":"text","text":"live answer"}]}}"#,
                "\n",
            ),
        )
        .unwrap();
        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CLAUDE_CODE),
            session_id: "severed".into(),
            storage: StorageLocator::File { path },
        };
        let mut service = HarnessSessionService::new();

        let viewed = service.handle(request(
            1,
            "harness.v1.sessions.load",
            json!({"locator": locator}),
        ));
        let session = &viewed["result"]["session"];
        assert_eq!(session["fidelity"], "semantic");
        assert_eq!(session["messages"].as_array().unwrap().len(), 2);
        assert!(session["residue"].as_array().unwrap().iter().any(|entry| {
            entry
                .as_str()
                .is_some_and(|entry| entry.contains("live-a") && entry.contains("pruned"))
        }));

        // Asking a READ surface for a lossless reconstruction gets the strict
        // refusal back, unchanged.
        let strict = service.handle(request(
            2,
            "harness.v1.sessions.load",
            json!({"locator": locator, "fidelity": "byte_lossless"}),
        ));
        assert!(strict["error"]["message"]
            .as_str()
            .unwrap()
            .contains("cannot reconstruct lossless Claude continuation"));

        // Transfer/continuation surfaces have no view mode at all.
        let translated = service.handle(request(
            3,
            "harness.v1.sessions.translate",
            json!({"locator": locator, "target_harness": "codex"}),
        ));
        assert!(translated["error"]["message"]
            .as_str()
            .unwrap()
            .contains("cannot reconstruct lossless Claude continuation"));
        let resumed = service.handle(request(
            4,
            "harness.v1.sessions.resume_instructions",
            json!({"locator": locator}),
        ));
        assert!(resumed["error"]["message"]
            .as_str()
            .unwrap()
            .contains("cannot reconstruct lossless Claude continuation"));

        let _ = std::fs::remove_dir_all(&temp);
    }

    #[test]
    fn structured_resume_launches_cover_gemini_goose_and_supercode() {
        let gemini = resume_launch(
            HarnessId::GEMINI,
            "gemini-session",
            Path::new("/tmp/project"),
            ResumePolicy::Yolo,
        )
        .unwrap_or_else(|_| panic!("Gemini resume launch must be registered"));
        assert_eq!(gemini.program, "gemini");
        assert_eq!(gemini.arguments, ["--yolo", "--resume", "gemini-session"]);

        let goose = resume_launch(
            HarnessId::GOOSE,
            "goose-session",
            Path::new("/tmp/project"),
            ResumePolicy::Yolo,
        )
        .unwrap_or_else(|_| panic!("Goose resume launch must be registered"));
        assert_eq!(goose.program, "goose");
        assert_eq!(
            goose.arguments,
            ["session", "--resume", "--session-id", "goose-session"]
        );

        let supercode = resume_launch(
            HarnessId::SUPERCODE,
            "supercode-session",
            Path::new("/tmp/project"),
            ResumePolicy::Yolo,
        )
        .unwrap_or_else(|_| panic!("Supercode resume launch must be registered"));
        assert_eq!(supercode.program, "supercode");
        assert_eq!(
            supercode.arguments,
            ["--dangerous", "resume", "supercode-session"]
        );
    }

    #[test]
    fn diagonal_artifacts_preserve_claude_subagents_and_grok_bundle_members() {
        let temp = std::env::temp_dir().join(format!(
            "supercode-harness-artifact-{}-{}",
            std::process::id(),
            generated_session_id()
        ));
        let main_path = temp.join("parent.jsonl");
        let subagent_path = temp.join("parent/subagents/agent-child.jsonl");
        std::fs::create_dir_all(subagent_path.parent().unwrap()).unwrap();
        let fixture = std::fs::read_to_string(
            PathBuf::from(env!("CARGO_MANIFEST_DIR"))
                .join("tests/fixtures/claude_code_session.jsonl"),
        )
        .unwrap();
        let parent = fixture.trim_end_matches('\n');
        let child = fixture.trim_end_matches('\n');
        std::fs::write(&main_path, parent).unwrap();
        std::fs::write(&subagent_path, child).unwrap();
        let locator = SessionLocator {
            harness: HarnessId::from(HarnessId::CLAUDE_CODE),
            session_id: "213bb148-51ea-453f-9206-f8b4b1168547".into(),
            storage: StorageLocator::File {
                path: main_path.clone(),
            },
        };
        let mut service = HarnessSessionService::new();
        let claude = service.handle(request(
            1,
            "harness.v1.sessions.translate",
            json!({"locator": locator, "target_harness": "claude-code"}),
        ));
        let artifact = &claude["result"]["artifact"];
        assert_eq!(artifact["fidelity"], "byte_lossless");
        assert_eq!(artifact["content"], parent);
        let files = artifact["files"].as_array().unwrap();
        assert!(files.iter().any(|file| {
            file["role"] == "subagent"
                && file["path"]
                    .as_str()
                    .is_some_and(|path| path.ends_with("/subagents/agent-child.jsonl"))
                && file["content"] == child
        }));
        assert!(!artifact["content"].as_str().unwrap().ends_with('\n'));

        let grok = service.handle(request(
            2,
            "harness.v1.sessions.translate",
            json!({"locator": grok_locator(), "target_harness": "grok"}),
        ));
        let files = grok["result"]["artifact"]["files"].as_array().unwrap();
        for name in ["summary.json", "updates.jsonl"] {
            let expected = std::fs::read_to_string(
                PathBuf::from(env!("CARGO_MANIFEST_DIR"))
                    .join("tests/fixtures/grok_session")
                    .join(name),
            )
            .unwrap();
            assert!(files.iter().any(|file| {
                file["path"] == name && file["role"] == "bundle" && file["content"] == expected
            }));
        }
        std::fs::remove_dir_all(temp).ok();
    }

    #[test]
    fn every_non_grok_handoff_mints_and_uses_a_fresh_target_identity() {
        let mut service = HarnessSessionService::new();
        let source = pi_locator();
        for (target, format) in [
            ("claude-code", SessionFormat::ClaudeCode),
            ("codex", SessionFormat::Codex),
            ("opencode", SessionFormat::OpenCode),
            ("pi", SessionFormat::Pi),
        ] {
            let result = service.handle(request(
                1,
                "harness.v1.sessions.handoff",
                json!({"locator": source, "target_harness": target, "cwd": "/tmp/project"}),
            ));
            let artifact = &result["result"]["artifact"];
            let target_id = artifact["session_id"].as_str().unwrap();
            assert_ne!(target_id, source.session_id, "{target}");
            let parsed = Session::load_str(artifact["content"].as_str().unwrap(), format).unwrap();
            assert_eq!(
                parsed.meta.session_id.as_deref(),
                Some(target_id),
                "{target}"
            );
            if target != "pi" {
                assert!(result["result"]["launch"]["arguments"]
                    .as_array()
                    .unwrap()
                    .iter()
                    .any(|argument| argument == target_id));
            }
            if target == "opencode" {
                assert!(target_id.starts_with("ses_"));
                fn assert_session_ids(value: &Value, target_id: &str) {
                    match value {
                        Value::Object(fields) => {
                            if let Some(session_id) = fields.get("sessionID") {
                                assert_eq!(session_id, target_id);
                            }
                            for child in fields.values() {
                                assert_session_ids(child, target_id);
                            }
                        }
                        Value::Array(values) => {
                            for child in values {
                                assert_session_ids(child, target_id);
                            }
                        }
                        _ => {}
                    }
                }
                let document: Value =
                    serde_json::from_str(artifact["content"].as_str().unwrap()).unwrap();
                assert_session_ids(&document, target_id);
            }
        }

        let first = service.handle(request(
            2,
            "harness.v1.sessions.handoff",
            json!({"locator": source, "target_harness": "codex"}),
        ));
        let second = service.handle(request(
            3,
            "harness.v1.sessions.handoff",
            json!({"locator": source, "target_harness": "codex"}),
        ));
        assert_ne!(
            first["result"]["artifact"]["session_id"],
            second["result"]["artifact"]["session_id"]
        );
    }

    #[test]
    fn grok_handoff_uses_the_official_importer_contract() {
        let mut service = HarnessSessionService::new();
        let source = opencode_locator();
        let response = service.handle(request(
            1,
            "harness.v1.sessions.handoff",
            json!({
                "locator": source,
                "target_harness": "grok",
                "cwd": "/tmp/grok-handoff-project",
            }),
        ));
        let result = &response["result"];

        // The target is Grok, but the artifact truthfully names the Claude Code wire
        // format accepted by Grok's official importer. Raw Grok chat_history JSONL is
        // not a complete stock-resumable bundle.
        assert_eq!(result["artifact"]["target_harness"], "claude-code");
        assert!(result["artifact"]["suggested_filename"]
            .as_str()
            .unwrap()
            .ends_with(".grok-import.claude-code.jsonl"));
        let artifact = Session::load_str(
            result["artifact"]["content"].as_str().unwrap(),
            SessionFormat::ClaudeCode,
        )
        .unwrap();
        assert_eq!(
            artifact.meta.cwd.as_deref(),
            Some(Path::new("/tmp/grok-handoff-project"))
        );
        let target_session_id = artifact.meta.session_id.as_deref().unwrap();
        assert_eq!(target_session_id.len(), 36);
        assert_eq!(target_session_id.as_bytes()[14], b'4');
        assert_ne!(target_session_id, opencode_locator().session_id);
        assert_eq!(
            result["artifact"]["session_id"],
            artifact.meta.session_id.as_deref().unwrap()
        );

        assert_eq!(
            result["materialize"]["arguments"],
            json!(["import", "--json", "{artifact_path}"])
        );
        assert_eq!(
            result["launch"]["arguments"],
            json!(["--resume", "{imported_session_id}", "--fork-session"])
        );
        assert!(result["note"]
            .as_str()
            .unwrap()
            .contains("outcome=imported"));
        assert!(!result["launch"]["arguments"]
            .as_array()
            .unwrap()
            .iter()
            .any(|argument| argument == &opencode_locator().session_id));
    }

    #[tokio::test]
    async fn inventory_rejects_unknown_harnesses_and_runtime_attach_is_honest() {
        let mut service = HarnessSessionService::new();
        let inventory = service
            .handle_async(request(
                1,
                "harness.v1.harnesses.list",
                json!({"harnesses": ["missing"]}),
            ))
            .await;
        assert_eq!(inventory["error"]["code"], -32602);

        let attached = service
            .handle_async(request(
                2,
                "harness.v1.runtimes.attach_existing",
                json!({"harness": "codex", "runtime_id": "thread-1"}),
            ))
            .await;
        assert_eq!(attached["error"]["code"], -32000);
        assert!(attached["error"]["message"]
            .as_str()
            .unwrap()
            .contains("runtimes.resume"));
    }

    #[test]
    fn invalid_params_and_unknown_methods_use_json_rpc_errors() {
        let mut service = HarnessSessionService::new();
        let invalid = service.handle(request(1, "harness.v1.sessions.load", json!({})));
        assert_eq!(invalid["error"]["code"], -32602);
        let unknown = service.handle(request(2, "harness.v1.unknown", json!({})));
        assert_eq!(unknown["error"]["code"], -32601);
    }

    #[cfg(unix)]
    #[tokio::test]
    // The test mutates process-wide harness environment and deliberately
    // holds the global test lock until every async runtime operation ends.
    #[allow(clippy::await_holding_lock)]
    async fn async_service_drives_a_generic_acp_runtime() {
        let _environment_guard = crate::live_runtime::test_environment_lock();
        let script = r#"
            i=0
            while IFS= read -r line; do
              i=$((i + 1))
              case "$i" in
                1) printf '%s\n' '{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentCapabilities":{},"authMethods":[]}}' ;;
                2) printf '%s\n' '{"jsonrpc":"2.0","id":2,"result":{"sessionId":"svc_acp"}}' ;;
                3)
                  printf '%s\n' '{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"svc_acp","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"ok"}}}}'
                  printf '%s\n' '{"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}'
                  ;;
                4)
                  printf '%s\n' '{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"svc_acp","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"from terminal"}}}}'
                  printf '%s\n' '{"jsonrpc":"2.0","id":4,"result":{"stopReason":"end_turn"}}'
                  ;;
              esac
            done
        "#;
        let mut service = HarnessSessionService::new();
        let started = service
            .handle_async(request(
                1,
                "harness.v1.runtimes.start",
                json!({
                    "harness": "codex",
                    "protocol": "acp",
                    "cwd": std::env::current_dir().unwrap(),
                    "launch": {"program": "/bin/sh", "arguments": ["-c", script], "env": {}},
                }),
            ))
            .await;
        assert_eq!(started["result"]["connection"], "runtime-1");
        assert_eq!(started["result"]["handle"]["runtime_id"], "svc_acp");

        let terminal = service
            .handle_async(request(
                9,
                "harness.v1.runtimes.terminal_instructions",
                json!({"connection":"runtime-1"}),
            ))
            .await;
        let arguments = terminal["result"]["launch"]["arguments"]
            .as_array()
            .expect("hosted runtime should return terminal arguments");
        let endpoint_index = arguments
            .iter()
            .position(|value| value == "--endpoint")
            .expect("terminal command should use an opaque endpoint");
        let endpoint = LiveRuntimeEndpoint::parse(
            arguments[endpoint_index + 1]
                .as_str()
                .expect("endpoint argument should be text"),
        )
        .unwrap();
        assert!(!terminal.to_string().contains("Bearer"));
        let workspace = std::env::current_dir().unwrap();
        let receipt = resolve_live_runtime(
            &endpoint,
            &LiveRuntimeSource {
                harness: "codex".into(),
                session_id: "svc_acp".into(),
                workspace,
            },
        )
        .unwrap();
        let remote = crate::HttpFrontendRuntime::connect(receipt.base_url, receipt.token)
            .await
            .unwrap();
        let mut attachment = crate::FrontendRuntime::attach(remote.as_ref(), 100)
            .await
            .unwrap();

        let sent = service
            .handle_async(request(
                2,
                "harness.v1.runtimes.send_input",
                json!({"connection": "runtime-1", "text": "hi"}),
            ))
            .await;
        assert_eq!(sent["result"]["turn_id"], "3");

        let mut events = Vec::new();
        for _ in 0..20 {
            events.extend(service.poll_runtimes().await);
            if events.len() >= 2 {
                break;
            }
            tokio::time::sleep(Duration::from_millis(2)).await;
        }
        assert!(events
            .iter()
            .any(|event| { event["params"]["event"]["kind"] == "session/update" }));
        assert!(events.iter().any(|event| {
            event["params"]["event"]["kind"] == "supercode/acp_request_completed"
        }));

        let saw_editor_reply = tokio::time::timeout(Duration::from_secs(2), async {
            loop {
                let event = attachment.next_event().await.unwrap();
                if event.kind == "text_delta" && event.payload["text"] == "ok" {
                    break;
                }
            }
        })
        .await;
        assert!(
            saw_editor_reply.is_ok(),
            "terminal should observe the editor-driven turn"
        );

        crate::FrontendRuntime::submit(remote.as_ref(), "DRIVE FROM TERMINAL".into())
            .await
            .unwrap();
        let saw_terminal_reply = tokio::time::timeout(Duration::from_secs(2), async {
            loop {
                let event = attachment.next_event().await.unwrap();
                if event.kind == "text_delta" && event.payload["text"] == "from terminal" {
                    break;
                }
            }
        })
        .await;
        assert!(
            saw_terminal_reply.is_ok(),
            "terminal should drive the same runtime"
        );

        let closed = service
            .handle_async(request(
                3,
                "harness.v1.runtimes.close",
                json!({"connection": "runtime-1"}),
            ))
            .await;
        assert_eq!(closed["result"]["closed"], true);
    }
}