opencode_orchestrator_mcp/

tools.rs

//! Tool implementations for orchestrator MCP server.

use crate::config;
use crate::logging;
use crate::server::OrchestratorServer;
use crate::token_tracker::TokenTracker;
use crate::types::ChangeStats;
use crate::types::CommandInfo;
use crate::types::GetSessionStateInput;
use crate::types::GetSessionStateOutput;
use crate::types::ListCommandsInput;
use crate::types::ListCommandsOutput;
use crate::types::ListSessionsInput;
use crate::types::ListSessionsOutput;
use crate::types::OrchestratorRunInput;
use crate::types::OrchestratorRunOutput;
use crate::types::PermissionReply;
use crate::types::QuestionAction;
use crate::types::QuestionInfoView;
use crate::types::QuestionOptionView;
use crate::types::RespondPermissionInput;
use crate::types::RespondPermissionOutput;
use crate::types::RespondQuestionInput;
use crate::types::RespondQuestionOutput;
use crate::types::RunStatus;
use crate::types::SessionStatusSummary;
use crate::types::SessionSummary;
use crate::types::ToolCallSummary;
use crate::types::ToolStateSummary;
use agentic_logging::CallTimer;
use agentic_logging::ToolCallRecord;
use agentic_tools_core::Tool;
use agentic_tools_core::ToolContext;
use agentic_tools_core::ToolError;
use agentic_tools_core::ToolRegistry;
use agentic_tools_core::fmt::TextFormat;
use agentic_tools_core::fmt::TextOptions;
use futures::future::BoxFuture;
use opencode_rs::types::event::Event;
use opencode_rs::types::message::CommandRequest;
use opencode_rs::types::message::Message;
use opencode_rs::types::message::Part;
use opencode_rs::types::message::PromptPart;
use opencode_rs::types::message::PromptRequest;
use opencode_rs::types::message::ToolState;
use opencode_rs::types::permission::PermissionReply as ApiPermissionReply;
use opencode_rs::types::permission::PermissionReplyRequest;
use opencode_rs::types::question::QuestionReply;
use opencode_rs::types::question::QuestionRequest;
use opencode_rs::types::session::CreateSessionRequest;
use opencode_rs::types::session::SessionStatusInfo;
use opencode_rs::types::session::SummarizeRequest;
use serde::Serialize;
use std::sync::Arc;
use std::time::Duration;
use tokio::sync::OnceCell;
use tokio::task::JoinHandle;

const SERVER_NAME: &str = "opencode-orchestrator-mcp";

#[derive(Debug, Clone, Default)]
struct ToolLogMeta {
    token_usage: Option<agentic_logging::TokenUsage>,
    token_usage_saturated: bool,
}

struct RunOutcome {
    output: OrchestratorRunOutput,
    log_meta: ToolLogMeta,
}

impl RunOutcome {
    fn without_tokens(output: OrchestratorRunOutput) -> Self {
        Self {
            output,
            log_meta: ToolLogMeta::default(),
        }
    }

    fn with_tracker(output: OrchestratorRunOutput, token_tracker: &TokenTracker) -> Self {
        let (token_usage, token_usage_saturated) = token_tracker.to_log_token_usage();
        Self {
            output,
            log_meta: ToolLogMeta {
                token_usage,
                token_usage_saturated,
            },
        }
    }
}

fn request_json<T: Serialize>(request: &T) -> serde_json::Value {
    serde_json::to_value(request)
        .unwrap_or_else(|error| serde_json::json!({"serialization_error": error.to_string()}))
}

fn log_tool_success<TReq: Serialize, TOut: TextFormat>(
    timer: &CallTimer,
    tool: &str,
    request: &TReq,
    output: &TOut,
    log_meta: ToolLogMeta,
    write_markdown: bool,
) {
    let (completed_at, duration_ms) = timer.finish();
    let rendered = output.fmt_text(&TextOptions::default());
    let response_file = write_markdown
        .then(|| logging::write_markdown_best_effort(completed_at, &timer.call_id, &rendered))
        .flatten();

    let record = ToolCallRecord {
        call_id: timer.call_id.clone(),
        server: SERVER_NAME.into(),
        tool: tool.into(),
        started_at: timer.started_at,
        completed_at,
        duration_ms,
        request: request_json(request),
        response_file,
        success: true,
        error: None,
        model: None,
        token_usage: log_meta.token_usage,
        summary: log_meta
            .token_usage_saturated
            .then(|| serde_json::json!({"token_usage_saturated": true})),
    };

    logging::append_record_best_effort(&record);
}

fn log_tool_error<TReq: Serialize>(
    timer: &CallTimer,
    tool: &str,
    request: &TReq,
    error: &ToolError,
) {
    let (completed_at, duration_ms) = timer.finish();
    let record = ToolCallRecord {
        call_id: timer.call_id.clone(),
        server: SERVER_NAME.into(),
        tool: tool.into(),
        started_at: timer.started_at,
        completed_at,
        duration_ms,
        request: request_json(request),
        response_file: None,
        success: false,
        error: Some(error.to_string()),
        model: None,
        token_usage: None,
        summary: None,
    };

    logging::append_record_best_effort(&record);
}

// ============================================================================
// run
// ============================================================================

/// Tool for starting or resuming `OpenCode` sessions.
///
/// Handles session creation, prompt/command execution, SSE event monitoring,
/// and permission request detection. Returns when the session completes or
/// when a permission is requested.
#[derive(Clone)]
pub struct OrchestratorRunTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl OrchestratorRunTool {
    /// Create a new `OrchestratorRunTool` with the given server cell.
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }

    /// Finalize a completed session by fetching messages and optionally triggering summarization.
    ///
    /// This is called when we detect the session is idle, either via SSE `SessionIdle` event
    /// or via polling `sessions().status()`.
    ///
    /// Uses bounded retry with backoff (0/50/100/200/400ms) if assistant text is not immediately
    /// available, handling the race condition where the session becomes idle before messages
    /// are fully persisted.
    async fn finalize_completed(
        client: &opencode_rs::Client,
        session_id: String,
        token_tracker: &TokenTracker,
        mut warnings: Vec<String>,
    ) -> Result<OrchestratorRunOutput, ToolError> {
        // Bounded backoff delays for message extraction retry (~750ms total budget)
        const BACKOFFS_MS: &[u64] = &[0, 50, 100, 200, 400];

        let mut response: Option<String> = None;

        for (attempt, &delay_ms) in BACKOFFS_MS.iter().enumerate() {
            if delay_ms > 0 {
                tokio::time::sleep(Duration::from_millis(delay_ms)).await;
            }

            let messages = client
                .messages()
                .list(&session_id)
                .await
                .map_err(|e| ToolError::Internal(format!("Failed to list messages: {e}")))?;

            response = OrchestratorServer::extract_assistant_text(&messages);

            if response.is_some() {
                if attempt > 0 {
                    tracing::debug!(
                        session_id = %session_id,
                        attempt,
                        "assistant response became available after retry"
                    );
                }
                break;
            }
        }

        if response.is_none() {
            tracing::debug!(
                session_id = %session_id,
                "no assistant response found after bounded retry"
            );
        }

        // Handle context limit summarization if needed
        if token_tracker.compaction_needed
            && let (Some(pid), Some(mid)) = (&token_tracker.provider_id, &token_tracker.model_id)
        {
            let summarize_req = SummarizeRequest {
                provider_id: pid.clone(),
                model_id: mid.clone(),
                auto: None,
            };

            match client
                .sessions()
                .summarize(&session_id, &summarize_req)
                .await
            {
                Ok(_) => {
                    tracing::info!(session_id = %session_id, "context summarization triggered");
                    warnings.push("Context limit reached; summarization triggered".into());
                }
                Err(e) => {
                    tracing::warn!(session_id = %session_id, error = %e, "summarization failed");
                    warnings.push(format!("Summarization failed: {e}"));
                }
            }
        }

        Ok(OrchestratorRunOutput {
            session_id,
            status: RunStatus::Completed,
            response,
            partial_response: None,
            permission_request_id: None,
            permission_type: None,
            permission_patterns: vec![],
            question_request_id: None,
            questions: vec![],
            warnings,
        })
    }

    fn map_questions(req: &QuestionRequest) -> Vec<QuestionInfoView> {
        req.questions
            .iter()
            .map(|question| QuestionInfoView {
                question: question.question.clone(),
                header: question.header.clone(),
                options: question
                    .options
                    .iter()
                    .map(|option| QuestionOptionView {
                        label: option.label.clone(),
                        description: option.description.clone(),
                    })
                    .collect(),
                multiple: question.multiple,
                custom: question.custom,
            })
            .collect()
    }

    fn question_required_output(
        session_id: String,
        partial_response: Option<String>,
        request: &QuestionRequest,
        warnings: Vec<String>,
    ) -> OrchestratorRunOutput {
        OrchestratorRunOutput {
            session_id,
            status: RunStatus::QuestionRequired,
            response: None,
            partial_response,
            permission_request_id: None,
            permission_type: None,
            permission_patterns: vec![],
            question_request_id: Some(request.id.clone()),
            questions: Self::map_questions(request),
            warnings,
        }
    }

    async fn run_impl_outcome(&self, input: OrchestratorRunInput) -> Result<RunOutcome, ToolError> {
        // Input validation
        if input.session_id.is_none() && input.message.is_none() && input.command.is_none() {
            return Err(ToolError::InvalidInput(
                "Either session_id (to resume/check status) or message/command (to start work) is required"
                    .into(),
            ));
        }

        if input.command.is_some() && input.message.is_none() {
            return Err(ToolError::InvalidInput(
                "message is required when command is specified (becomes $ARGUMENTS for template expansion)"
                    .into(),
            ));
        }

        // Trim and validate message content
        let message = input.message.map(|m| m.trim().to_string());
        if let Some(ref m) = message
            && m.is_empty()
        {
            return Err(ToolError::InvalidInput(
                "message cannot be empty or whitespace-only".into(),
            ));
        }

        let wait_for_activity = input.wait_for_activity.unwrap_or(false);

        // Lazy initialization: spawn server on first tool call
        let server = self
            .server
            .get_or_try_init(OrchestratorServer::start_lazy)
            .await
            .map_err(|e| ToolError::Internal(e.to_string()))?;

        let client = server.client();

        tracing::debug!(
            command = ?input.command,
            has_message = message.is_some(),
            message_len = message.as_ref().map(String::len),
            session_id = ?input.session_id,
            "run: starting"
        );

        // 1. Resolve session: validate existing or create new
        let session_id = if let Some(sid) = input.session_id {
            // Validate session exists
            client.sessions().get(&sid).await.map_err(|e| {
                if e.is_not_found() {
                    ToolError::InvalidInput(format!(
                        "Session '{sid}' not found. Use list_sessions to discover sessions, \
                         or omit session_id to create a new session."
                    ))
                } else {
                    ToolError::Internal(format!("Failed to get session: {e}"))
                }
            })?;
            sid
        } else {
            // Create new session
            let session = client
                .sessions()
                .create(&CreateSessionRequest::default())
                .await
                .map_err(|e| ToolError::Internal(format!("Failed to create session: {e}")))?;

            {
                let mut spawned = server.spawned_sessions().write().await;
                spawned.insert(session.id.clone());
            }

            session.id
        };

        tracing::info!(session_id = %session_id, "run: session resolved");

        // 2. Check if session is already idle (for resume-only case)
        let status = client
            .sessions()
            .status_for(&session_id)
            .await
            .map_err(|e| ToolError::Internal(format!("Failed to get session status: {e}")))?;

        let is_idle = matches!(status, SessionStatusInfo::Idle);

        // 3. Check for pending permissions before doing anything else
        let pending_permissions = client
            .permissions()
            .list()
            .await
            .map_err(|e| ToolError::Internal(format!("Failed to list permissions: {e}")))?;

        let my_permission = pending_permissions
            .into_iter()
            .find(|p| p.session_id == session_id);

        if let Some(perm) = my_permission {
            tracing::info!(
                session_id = %session_id,
                permission_type = %perm.permission,
                "run: pending permission found"
            );
            return Ok(RunOutcome::without_tokens(OrchestratorRunOutput {
                session_id,
                status: RunStatus::PermissionRequired,
                response: None,
                partial_response: None,
                permission_request_id: Some(perm.id),
                permission_type: Some(perm.permission),
                permission_patterns: perm.patterns,
                question_request_id: None,
                questions: vec![],
                warnings: vec![],
            }));
        }

        let pending_questions = client
            .question()
            .list()
            .await
            .map_err(|e| ToolError::Internal(format!("Failed to list questions: {e}")))?;

        if let Some(question) = pending_questions
            .into_iter()
            .find(|question| question.session_id == session_id)
        {
            tracing::info!(session_id = %session_id, question_id = %question.id, "run: pending question found");
            return Ok(RunOutcome::without_tokens(Self::question_required_output(
                session_id,
                None,
                &question,
                vec![],
            )));
        }

        // 4. If no message/command and session is idle, just return current state
        // Uses finalize_completed to get retry logic for message extraction
        if message.is_none() && input.command.is_none() && is_idle && !wait_for_activity {
            let token_tracker = TokenTracker::with_threshold(server.compaction_threshold());
            let output =
                Self::finalize_completed(client, session_id, &token_tracker, vec![]).await?;
            return Ok(RunOutcome::with_tracker(output, &token_tracker));
        }

        // 5. Subscribe to SSE BEFORE sending prompt/command
        let mut subscription = client
            .subscribe_session(&session_id)
            .map_err(|e| ToolError::Internal(format!("Failed to subscribe to session: {e}")))?;

        // Track whether this call is dispatching new work (command or message)
        // vs just resuming/monitoring an existing session.
        let dispatched_new_work = input.command.is_some() || message.is_some() || wait_for_activity;
        let idle_grace = config::idle_grace();
        let mut idle_grace_deadline: Option<tokio::time::Instant> = None;
        let mut awaiting_idle_grace_check = false;

        if wait_for_activity && input.command.is_none() && message.is_none() {
            idle_grace_deadline = Some(tokio::time::Instant::now() + idle_grace);
        }

        // 6. Kick off the work
        let mut command_task: Option<JoinHandle<Result<(), String>>> = None;
        let mut command_name_for_logging: Option<String> = None;

        if let Some(command) = &input.command {
            command_name_for_logging = Some(command.clone());

            let cmd_client = client.clone();
            let cmd_session_id = session_id.clone();
            let cmd_name = command.clone();
            let cmd_arguments = message.clone().unwrap_or_default();

            command_task = Some(tokio::spawn(async move {
                let req = CommandRequest {
                    command: cmd_name,
                    arguments: cmd_arguments,
                    message_id: None,
                };

                cmd_client
                    .messages()
                    .command(&cmd_session_id, &req)
                    .await
                    .map(|_| ())
                    .map_err(|e| e.to_string())
            }));
        } else if let Some(msg) = &message {
            // Send prompt asynchronously
            let req = PromptRequest {
                parts: vec![PromptPart::Text {
                    text: msg.clone(),
                    synthetic: None,
                    ignored: None,
                    metadata: None,
                }],
                message_id: None,
                model: None,
                agent: None,
                no_reply: None,
                system: None,
                variant: None,
            };

            client
                .messages()
                .prompt_async(&session_id, &req)
                .await
                .map_err(|e| ToolError::Internal(format!("Failed to send prompt: {e}")))?;

            idle_grace_deadline = Some(tokio::time::Instant::now() + idle_grace);
        }

        // 7. Event loop: wait for completion or permission
        // Overall timeout to prevent infinite hangs (configurable, default 1 hour)
        let deadline = tokio::time::Instant::now() + server.session_deadline();
        let inactivity_timeout = server.inactivity_timeout();
        let mut last_activity_time = tokio::time::Instant::now();

        tracing::debug!(session_id = %session_id, "run: entering event loop");
        let mut token_tracker = TokenTracker::with_threshold(server.compaction_threshold());
        let mut partial_response = String::new();
        let warnings = Vec::new();

        let mut poll_interval = tokio::time::interval(Duration::from_secs(1));
        poll_interval.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);

        // Track whether we've observed the session as busy at least once.
        // This prevents completing immediately if we call run_impl on an already-idle
        // session before our new work has started processing.
        let mut observed_busy = false;

        // Track whether SSE is still active. If the stream closes, we fall back
        // to polling-only mode rather than returning an error.
        let mut sse_active = true;

        // === Post-subscribe status re-check (latency optimization) ===
        // If we're just monitoring (no new work dispatched), check if session is already idle.
        // This handles the race where session completed between our initial status check
        // and SSE subscription becoming ready.
        if !dispatched_new_work
            && let Ok(status) = client.sessions().status_for(&session_id).await
            && matches!(status, SessionStatusInfo::Idle)
        {
            tracing::debug!(
                session_id = %session_id,
                "session already idle on post-subscribe check"
            );
            let output =
                Self::finalize_completed(client, session_id, &token_tracker, warnings).await?;
            return Ok(RunOutcome::with_tracker(output, &token_tracker));
        }
        // If check fails or session is busy, continue to event loop

        loop {
            // Check timeout before processing
            let now = tokio::time::Instant::now();

            if now.duration_since(last_activity_time) >= inactivity_timeout {
                return Err(ToolError::Internal(format!(
                    "Session idle timeout: no activity for 5 minutes (session_id={session_id}). \
                     The session may still be running; use run(session_id=...) to check status."
                )));
            }

            if now >= deadline {
                return Err(ToolError::Internal(
                    "Session execution timed out after 1 hour. \
                     The session may still be running; use run with the session_id to check status."
                        .into(),
                ));
            }

            let command_task_active = command_task.is_some();

            tokio::select! {
                maybe_event = subscription.recv(), if sse_active => {
                    let Some(event) = maybe_event else {
                        // SSE stream closed - this can happen due to network issues,
                        // server restarts, or connection timeouts. Fall back to polling
                        // rather than failing immediately.
                        tracing::warn!(
                            session_id = %session_id,
                            "SSE stream closed unexpectedly; falling back to polling-only mode"
                        );
                        sse_active = false;
                        continue; // The poll_interval branch will now drive completion detection
                    };

                    // Track tokens (server is already initialized at this point)
                    token_tracker.observe_event(&event, |pid, mid| {
                        server.context_limit(pid, mid)
                    });

                    match event {
                        Event::PermissionAsked { properties } => {
                            tracing::info!(
                                session_id = %session_id,
                                permission_type = %properties.request.permission,
                                "run: permission requested"
                            );
                            return Ok(RunOutcome::with_tracker(OrchestratorRunOutput {
                                session_id,
                                status: RunStatus::PermissionRequired,
                                response: None,
                                partial_response: if partial_response.is_empty() {
                                    None
                                } else {
                                    Some(partial_response)
                                },
                                permission_request_id: Some(properties.request.id),
                                permission_type: Some(properties.request.permission),
                                permission_patterns: properties.request.patterns,
                                question_request_id: None,
                                questions: vec![],
                                warnings,
                            }, &token_tracker));
                        }

                        Event::QuestionAsked { properties } => {
                            return Ok(RunOutcome::with_tracker(Self::question_required_output(
                                session_id,
                                if partial_response.is_empty() {
                                    None
                                } else {
                                    Some(partial_response)
                                },
                                &properties.request,
                                warnings,
                            ), &token_tracker));
                        }

                        Event::MessagePartDelta { properties } => {
                            last_activity_time = tokio::time::Instant::now();
                            // Message streaming means session is actively processing
                            observed_busy = true;
                            awaiting_idle_grace_check = false;
                            // Collect streaming text from field-level delta events.
                            if let Some(delta) = &properties.delta {
                                partial_response.push_str(delta);
                            }
                        }

                        Event::MessagePartUpdated { .. } | Event::MessageUpdated { .. } => {
                            last_activity_time = tokio::time::Instant::now();
                            observed_busy = true;
                            awaiting_idle_grace_check = false;
                        }

                        Event::SessionError { properties } => {
                            let error_msg = properties
                                .error
                                .map_or_else(|| "Unknown error".to_string(), |e| format!("{e:?}"));
                            tracing::error!(
                                session_id = %session_id,
                                error = %error_msg,
                                "run: session error"
                            );
                            return Err(ToolError::Internal(format!("Session error: {error_msg}")));
                        }

                        Event::SessionIdle { .. } => {
                            tracing::debug!(session_id = %session_id, "received SessionIdle event");
                            let output = Self::finalize_completed(client, session_id, &token_tracker, warnings).await?;
                            return Ok(RunOutcome::with_tracker(output, &token_tracker));
                        }

                        _ => {
                            // Other events - continue
                        }
                    }
                }

                _ = poll_interval.tick() => {
                    // === 1. Permission fallback (check first, permissions take priority) ===
                    let pending = match client.permissions().list().await {
                        Ok(p) => p,
                        Err(e) => {
                            // Log but continue - permission list failure shouldn't block completion detection
                            tracing::warn!(
                                session_id = %session_id,
                                error = %e,
                                "failed to list permissions during poll fallback"
                            );
                            vec![]
                        }
                    };

                    if let Some(perm) = pending.into_iter().find(|p| p.session_id == session_id) {
                        tracing::debug!(
                            session_id = %session_id,
                            permission_id = %perm.id,
                            "detected pending permission via polling fallback"
                        );
                        return Ok(RunOutcome::with_tracker(OrchestratorRunOutput {
                            session_id,
                            status: RunStatus::PermissionRequired,
                            response: None,
                            partial_response: if partial_response.is_empty() {
                                None
                            } else {
                                Some(partial_response)
                                },
                                permission_request_id: Some(perm.id),
                                permission_type: Some(perm.permission),
                            permission_patterns: perm.patterns,
                            question_request_id: None,
                            questions: vec![],
                            warnings,
                        }, &token_tracker));
                    }

                    let pending_questions = match client.question().list().await {
                        Ok(questions) => questions,
                        Err(e) => {
                            tracing::warn!(
                                session_id = %session_id,
                                error = %e,
                                "failed to list questions during poll fallback"
                            );
                            vec![]
                        }
                    };

                    if let Some(question) = pending_questions
                        .into_iter()
                        .find(|question| question.session_id == session_id)
                    {
                        tracing::debug!(
                            session_id = %session_id,
                            question_id = %question.id,
                            "detected pending question via polling fallback"
                        );
                        return Ok(RunOutcome::with_tracker(Self::question_required_output(
                            session_id,
                            if partial_response.is_empty() {
                                None
                            } else {
                                Some(partial_response)
                            },
                            &question,
                            warnings,
                        ), &token_tracker));
                    }

                    // === 2. Session idle detection fallback (NEW) ===
                    // This is the key fix for race conditions. If SSE missed SessionIdle,
                    // we detect completion via polling sessions().status_for(session_id).
                    match client.sessions().status_for(&session_id).await {
                        Ok(SessionStatusInfo::Busy | SessionStatusInfo::Retry { .. }) => {
                            last_activity_time = tokio::time::Instant::now();
                            observed_busy = true;
                            awaiting_idle_grace_check = false;
                            tracing::trace!(
                                session_id = %session_id,
                                "our session is busy/retry, waiting"
                            );
                        }
                        Ok(SessionStatusInfo::Idle) => {
                            if !dispatched_new_work || observed_busy {
                                // Session is idle AND either:
                                // - We didn't dispatch new work (just monitoring), OR
                                // - We did dispatch work and have seen it become busy at least once
                                //
                                // This guards against completing before our work starts processing.
                                tracing::debug!(
                                    session_id = %session_id,
                                    dispatched_new_work = dispatched_new_work,
                                    observed_busy = observed_busy,
                                    "detected session idle via polling fallback"
                                );
                                let output = Self::finalize_completed(client, session_id, &token_tracker, warnings).await?;
                                return Ok(RunOutcome::with_tracker(output, &token_tracker));
                            }

                            let Some(deadline) = idle_grace_deadline else {
                                tracing::trace!(
                                    session_id = %session_id,
                                    command_task_active = command_task_active,
                                    "idle seen before dispatch confirmed; waiting"
                                );
                                continue;
                            };

                            let now = tokio::time::Instant::now();
                            if now >= deadline {
                                tracing::debug!(
                                    session_id = %session_id,
                                    idle_grace_ms = idle_grace.as_millis(),
                                    "accepting idle via bounded idle grace (no busy observed)"
                                );
                                let output = Self::finalize_completed(client, session_id, &token_tracker, warnings).await?;
                                return Ok(RunOutcome::with_tracker(output, &token_tracker));
                            }

                            awaiting_idle_grace_check = true;
                            tracing::trace!(
                                session_id = %session_id,
                                remaining_ms = (deadline - now).as_millis(),
                                "idle detected before busy; waiting for idle-grace deadline"
                            );
                        }
                        Err(e) => {
                            // Log but continue - status check failure shouldn't block the loop
                            tracing::warn!(
                                session_id = %session_id,
                                error = %e,
                                "failed to get session status during poll fallback"
                            );
                        }
                    }
                }

                () = async {
                    match idle_grace_deadline {
                        Some(deadline) => tokio::time::sleep_until(deadline).await,
                        None => std::future::pending::<()>().await,
                    }
                }, if awaiting_idle_grace_check => {
                    awaiting_idle_grace_check = false;

                    match client.sessions().status_for(&session_id).await {
                        Ok(SessionStatusInfo::Idle) => {
                            tracing::debug!(session_id = %session_id, "idle-grace deadline reached; finalizing");
                            let output = Self::finalize_completed(client, session_id, &token_tracker, warnings).await?;
                            return Ok(RunOutcome::with_tracker(output, &token_tracker));
                        }
                        Ok(SessionStatusInfo::Busy | SessionStatusInfo::Retry { .. }) => {
                            last_activity_time = tokio::time::Instant::now();
                            observed_busy = true;
                        }
                        Err(e) => {
                            tracing::warn!(
                                session_id = %session_id,
                                error = %e,
                                "status check failed at idle-grace deadline"
                            );
                        }
                    }
                }

                cmd_result = async {
                    match command_task.as_mut() {
                        Some(handle) => Some(handle.await),
                        None => {
                            std::future::pending::<
                                Option<Result<Result<(), String>, tokio::task::JoinError>>,
                            >()
                            .await
                        }
                    }
                }, if command_task_active => {
                    match cmd_result {
                        Some(Ok(Ok(()))) => {
                            idle_grace_deadline = Some(tokio::time::Instant::now() + idle_grace);
                            tracing::debug!(
                                session_id = %session_id,
                                command = ?command_name_for_logging,
                                "run: command dispatch completed successfully"
                            );
                            command_task = None;
                        }
                        Some(Ok(Err(e))) => {
                            tracing::error!(
                                session_id = %session_id,
                                command = ?command_name_for_logging,
                                error = %e,
                                "run: command dispatch failed"
                            );
                            return Err(ToolError::Internal(format!(
                                "Failed to execute command '{}': {e}",
                                command_name_for_logging.as_deref().unwrap_or("unknown")
                            )));
                        }
                        Some(Err(join_err)) => {
                            tracing::error!(
                                session_id = %session_id,
                                command = ?command_name_for_logging,
                                error = %join_err,
                                "run: command task panicked"
                            );
                            return Err(ToolError::Internal(format!("Command task panicked: {join_err}")));
                        }
                        None => {
                            unreachable!("command_task_active guard should prevent None");
                        }
                    }
                }
            }
        }
    }
}

impl Tool for OrchestratorRunTool {
    type Input = OrchestratorRunInput;
    type Output = OrchestratorRunOutput;
    const NAME: &'static str = "run";
    const DESCRIPTION: &'static str = r#"Start or resume an OpenCode session. Optionally run a named command or send a raw prompt.

Returns when:
- status=completed: Session finished executing. Response contains final assistant output.
- status=permission_required: Session needs permission approval. Call respond_permission to continue.
- status=question_required: Session needs question answers. Call respond_question to continue.

Parameters:
- session_id: Existing session to resume (omit to create new)
- command: OpenCode command name (e.g., "research", "implement_plan")
- message: Prompt text or $ARGUMENTS for command template

Examples:
- New session with prompt: run(message="explain this code")
- New session with command: run(command="research", message="caching strategies")
- Resume session: run(session_id="...", message="continue")
- Check status: run(session_id="...")"#;

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let this = self.clone();
        Box::pin(async move {
            let timer = CallTimer::start();
            match this.run_impl_outcome(input.clone()).await {
                Ok(outcome) => {
                    log_tool_success(
                        &timer,
                        Self::NAME,
                        &input,
                        &outcome.output,
                        outcome.log_meta,
                        true,
                    );
                    Ok(outcome.output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &input, &error);
                    Err(error)
                }
            }
        })
    }
}

// ============================================================================
// list_sessions
// ============================================================================

/// Tool for listing available `OpenCode` sessions in the current directory.
#[derive(Clone)]
pub struct ListSessionsTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl ListSessionsTool {
    /// Create a new `ListSessionsTool` with the given server cell.
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }
}

impl Tool for ListSessionsTool {
    type Input = ListSessionsInput;
    type Output = ListSessionsOutput;
    const NAME: &'static str = "list_sessions";
    const DESCRIPTION: &'static str =
        "List available OpenCode sessions in the current directory context.";

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let server_cell = Arc::clone(&self.server);
        Box::pin(async move {
            let timer = CallTimer::start();
            let result: Result<ListSessionsOutput, ToolError> = async {
                let server = server_cell
                    .get_or_try_init(OrchestratorServer::start_lazy)
                    .await
                    .map_err(|e| ToolError::Internal(e.to_string()))?;

                let sessions =
                    server.client().sessions().list().await.map_err(|e| {
                        ToolError::Internal(format!("Failed to list sessions: {e}"))
                    })?;
                let status_map = server.client().sessions().status_map().await.ok();
                let spawned = server.spawned_sessions().read().await;

                let limit = input.limit.unwrap_or(20);
                let summaries: Vec<SessionSummary> = sessions
                    .into_iter()
                    .take(limit)
                    .map(|s| {
                        let status =
                            status_map
                                .as_ref()
                                .map(|status_map| match status_map.get(&s.id) {
                                    Some(SessionStatusInfo::Busy) => SessionStatusSummary::Busy,
                                    Some(SessionStatusInfo::Retry {
                                        attempt,
                                        message,
                                        next,
                                    }) => SessionStatusSummary::Retry {
                                        attempt: *attempt,
                                        message: message.clone(),
                                        next: *next,
                                    },
                                    Some(SessionStatusInfo::Idle) | None => {
                                        SessionStatusSummary::Idle
                                    }
                                });

                        let change_stats = s.summary.as_ref().map(|summary| ChangeStats {
                            additions: summary.additions,
                            deletions: summary.deletions,
                            files: summary.files,
                        });

                        SessionSummary {
                            launched_by_you: spawned.contains(&s.id),
                            created: s.time.as_ref().map(|t| t.created),
                            updated: s.time.as_ref().map(|t| t.updated),
                            directory: s.directory,
                            title: s.title,
                            id: s.id,
                            status,
                            change_stats,
                        }
                    })
                    .collect();

                Ok(ListSessionsOutput {
                    sessions: summaries,
                })
            }
            .await;

            match result {
                Ok(output) => {
                    log_tool_success(
                        &timer,
                        Self::NAME,
                        &input,
                        &output,
                        ToolLogMeta::default(),
                        false,
                    );
                    Ok(output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &input, &error);
                    Err(error)
                }
            }
        })
    }
}

fn count_pending_messages(messages: &[Message]) -> usize {
    let mut pending = 0;

    for message in messages.iter().rev() {
        if message.role() == "user" {
            pending += 1;
        } else if message.role() == "assistant" {
            break;
        }
    }

    pending
}

fn get_last_activity_time(messages: &[Message], fallback: Option<i64>) -> Option<i64> {
    messages.last().map_or(fallback, |message| {
        Some(
            message
                .info
                .time
                .completed
                .unwrap_or(message.info.time.created),
        )
    })
}

fn extract_recent_tool_calls(messages: &[Message], limit: usize) -> Vec<ToolCallSummary> {
    let mut tool_calls = Vec::new();

    for message in messages.iter().rev() {
        for part in message.parts.iter().rev() {
            if let Part::Tool {
                call_id,
                tool,
                state,
                ..
            } = part
            {
                let (state, started_at, completed_at) = match state {
                    Some(ToolState::Running(running)) => {
                        (ToolStateSummary::Running, Some(running.time.start), None)
                    }
                    Some(ToolState::Completed(completed)) => (
                        ToolStateSummary::Completed,
                        Some(completed.time.start),
                        Some(completed.time.end),
                    ),
                    Some(ToolState::Error(error)) => (
                        ToolStateSummary::Error {
                            message: error.error.clone(),
                        },
                        Some(error.time.start),
                        Some(error.time.end),
                    ),
                    _ => (ToolStateSummary::Pending, None, None),
                };

                tool_calls.push(ToolCallSummary {
                    call_id: call_id.clone(),
                    tool_name: tool.clone(),
                    state,
                    started_at,
                    completed_at,
                });

                if tool_calls.len() >= limit {
                    return tool_calls;
                }
            }
        }
    }

    tool_calls
}

/// Tool for getting detailed state of a specific `OpenCode` session.
#[derive(Clone)]
pub struct GetSessionStateTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl GetSessionStateTool {
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }
}

impl Tool for GetSessionStateTool {
    type Input = GetSessionStateInput;
    type Output = GetSessionStateOutput;
    const NAME: &'static str = "get_session_state";
    const DESCRIPTION: &'static str = "Get detailed state of a specific session including status, pending messages, and recent tool calls.";

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let server_cell = Arc::clone(&self.server);
        Box::pin(async move {
            let timer = CallTimer::start();
            let result: Result<GetSessionStateOutput, ToolError> = async {
                let server = server_cell
                    .get_or_try_init(OrchestratorServer::start_lazy)
                    .await
                    .map_err(|e| ToolError::Internal(e.to_string()))?;

                let client = server.client();
                let session_id = &input.session_id;

                let session = client.sessions().get(session_id).await.map_err(|e| {
                    if e.is_not_found() {
                        ToolError::InvalidInput(format!(
                            "Session '{session_id}' not found. Use list_sessions to discover available sessions."
                        ))
                    } else {
                        ToolError::Internal(format!("Failed to get session: {e}"))
                    }
                })?;

                let status = match client.sessions().status_for(session_id).await.map_err(|e| {
                    ToolError::Internal(format!("Failed to get session status: {e}"))
                })? {
                    SessionStatusInfo::Busy => SessionStatusSummary::Busy,
                    SessionStatusInfo::Retry {
                        attempt,
                        message,
                        next,
                    } => SessionStatusSummary::Retry {
                        attempt,
                        message,
                        next,
                    },
                    SessionStatusInfo::Idle => SessionStatusSummary::Idle,
                };

                let messages = client.messages().list(session_id).await.map_err(|e| {
                    ToolError::Internal(format!("Failed to list messages: {e}"))
                })?;
                let pending_message_count = count_pending_messages(&messages);
                let last_activity = get_last_activity_time(
                    &messages,
                    session.time.as_ref().map(|time| time.updated),
                );
                let recent_tool_calls = extract_recent_tool_calls(&messages, 10);

                let spawned = server.spawned_sessions().read().await;
                let launched_by_you = spawned.contains(session_id);

                Ok(GetSessionStateOutput {
                    session_id: session.id,
                    title: session.title,
                    directory: session.directory,
                    status,
                    launched_by_you,
                    pending_message_count,
                    last_activity,
                    recent_tool_calls,
                })
            }
            .await;

            match result {
                Ok(output) => {
                    log_tool_success(
                        &timer,
                        Self::NAME,
                        &input,
                        &output,
                        ToolLogMeta::default(),
                        false,
                    );
                    Ok(output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &input, &error);
                    Err(error)
                }
            }
        })
    }
}

// ============================================================================
// list_commands
// ============================================================================

/// Tool for listing available `OpenCode` commands that can be executed.
#[derive(Clone)]
pub struct ListCommandsTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl ListCommandsTool {
    /// Create a new `ListCommandsTool` with the given server cell.
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }
}

impl Tool for ListCommandsTool {
    type Input = ListCommandsInput;
    type Output = ListCommandsOutput;
    const NAME: &'static str = "list_commands";
    const DESCRIPTION: &'static str = "List available OpenCode commands that can be used with run.";

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let server_cell = Arc::clone(&self.server);
        Box::pin(async move {
            let timer = CallTimer::start();
            let result: Result<ListCommandsOutput, ToolError> = async {
                let server = server_cell
                    .get_or_try_init(OrchestratorServer::start_lazy)
                    .await
                    .map_err(|e| ToolError::Internal(e.to_string()))?;

                let commands =
                    server.client().tools().commands().await.map_err(|e| {
                        ToolError::Internal(format!("Failed to list commands: {e}"))
                    })?;

                let command_infos: Vec<CommandInfo> = commands
                    .into_iter()
                    .map(|c| CommandInfo {
                        name: c.name,
                        description: c.description,
                    })
                    .collect();

                Ok(ListCommandsOutput {
                    commands: command_infos,
                })
            }
            .await;

            match result {
                Ok(output) => {
                    log_tool_success(
                        &timer,
                        Self::NAME,
                        &input,
                        &output,
                        ToolLogMeta::default(),
                        false,
                    );
                    Ok(output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &input, &error);
                    Err(error)
                }
            }
        })
    }
}

// ============================================================================
// respond_permission
// ============================================================================

/// Tool for responding to permission requests from `OpenCode` sessions.
///
/// After sending the reply, continues monitoring the session and returns
/// when the session completes or another permission is requested.
#[derive(Clone)]
pub struct RespondPermissionTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl RespondPermissionTool {
    /// Create a new `RespondPermissionTool` with the given server cell.
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }
}

impl Tool for RespondPermissionTool {
    type Input = RespondPermissionInput;
    type Output = RespondPermissionOutput;
    const NAME: &'static str = "respond_permission";
    const DESCRIPTION: &'static str = r#"Respond to a permission request from an OpenCode session.

After responding, continues monitoring the session and returns when complete or when another permission is required.

Parameters:
- session_id: Session with pending permission
- reply: "once" (allow this request), "always" (allow for matching patterns), or "reject" (deny)
- message: Optional message to include with reply"#;

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let server_cell = Arc::clone(&self.server);
        Box::pin(async move {
            let timer = CallTimer::start();
            let request = input.clone();
            let result: Result<(RespondPermissionOutput, ToolLogMeta), ToolError> = async {
                let server = server_cell
                    .get_or_try_init(OrchestratorServer::start_lazy)
                    .await
                    .map_err(|e| ToolError::Internal(e.to_string()))?;

                let client = server.client();

                // Find the pending permission for this session
                let mut pending =
                    client.permissions().list().await.map_err(|e| {
                        ToolError::Internal(format!("Failed to list permissions: {e}"))
                    })?;

                let perm = if let Some(req_id) = input.permission_request_id.as_deref() {
                    let idx = pending.iter().position(|p| p.id == req_id).ok_or_else(|| {
                        ToolError::InvalidInput(format!(
                            "No pending permission found with id '{req_id}'. \
                         (session_id='{}')",
                            input.session_id
                        ))
                    })?;

                    let perm = pending.remove(idx);

                    if perm.session_id != input.session_id {
                        return Err(ToolError::InvalidInput(format!(
                            "Permission request '{req_id}' belongs to session '{}', not '{}'.",
                            perm.session_id, input.session_id
                        )));
                    }

                    perm
                } else {
                    let mut perms: Vec<_> = pending
                        .into_iter()
                        .filter(|p| p.session_id == input.session_id)
                        .collect();

                    match perms.as_slice() {
                        [] => {
                            return Err(ToolError::InvalidInput(format!(
                                "No pending permission found for session '{}'. \
                             The permission may have already been responded to.",
                                input.session_id
                            )));
                        }
                        [_single] => perms.swap_remove(0),
                        multiple => {
                            let ids = multiple
                                .iter()
                                .map(|p| p.id.as_str())
                                .collect::<Vec<_>>()
                                .join(", ");
                            return Err(ToolError::InvalidInput(format!(
                                "Multiple pending permissions found for session '{}': {ids}. \
                             Please retry with permission_request_id (returned by run).",
                                input.session_id
                            )));
                        }
                    }
                };

                // Track if this is a rejection for post-processing
                let is_reject = matches!(input.reply, PermissionReply::Reject);

                // Capture permission details for warning message
                let permission_type = perm.permission.clone();
                let permission_patterns = perm.patterns.clone();

                // Capture baseline assistant text BEFORE sending reject
                // This lets us detect stale text after rejection
                let mut pre_warnings: Vec<String> = Vec::new();
                let baseline = if is_reject {
                    match client.messages().list(&input.session_id).await {
                        Ok(msgs) => OrchestratorServer::extract_assistant_text(&msgs),
                        Err(e) => {
                            pre_warnings.push(format!("Failed to fetch baseline messages: {e}"));
                            None
                        }
                    }
                } else {
                    None
                };

                // Convert our reply type to API type
                let api_reply = match input.reply {
                    PermissionReply::Once => ApiPermissionReply::Once,
                    PermissionReply::Always => ApiPermissionReply::Always,
                    PermissionReply::Reject => ApiPermissionReply::Reject,
                };

                // Send the reply
                client
                    .permissions()
                    .reply(
                        &perm.id,
                        &PermissionReplyRequest {
                            reply: api_reply,
                            message: input.message,
                        },
                    )
                    .await
                    .map_err(|e| {
                        ToolError::Internal(format!("Failed to reply to permission: {e}"))
                    })?;

                // Now continue monitoring the session using run logic
                let run_tool = OrchestratorRunTool::new(Arc::clone(&server_cell));
                let wait_for_activity = (!is_reject).then_some(true);
                let outcome = run_tool
                    .run_impl_outcome(OrchestratorRunInput {
                        session_id: Some(input.session_id),
                        command: None,
                        message: None,
                        wait_for_activity,
                    })
                    .await?;
                let mut out = outcome.output;

                // Merge pre-warnings
                out.warnings.extend(pre_warnings);

                // Apply rejection-aware output mutation
                if is_reject && matches!(out.status, RunStatus::Completed) {
                    let final_resp = out.response.as_deref();
                    let baseline_resp = baseline.as_deref();

                    // If response unchanged or None, it's stale pre-rejection text
                    if final_resp.is_none() || final_resp == baseline_resp {
                        out.response = None;
                        let patterns_str = if permission_patterns.is_empty() {
                            "(none)".to_string()
                        } else {
                            permission_patterns.join(", ")
                        };
                        out.warnings.push(format!(
                        "Permission rejected for '{permission_type}'. Patterns: {patterns_str}. \
                         Session stopped without generating a new assistant response."
                    ));
                        tracing::debug!(
                            permission_type = %permission_type,
                            "rejection override applied: response set to None"
                        );
                    }
                }

                Ok((out, outcome.log_meta))
            }
            .await;

            match result {
                Ok((output, log_meta)) => {
                    log_tool_success(&timer, Self::NAME, &request, &output, log_meta, true);
                    Ok(output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &request, &error);
                    Err(error)
                }
            }
        })
    }
}

// ============================================================================
// respond_question
// ============================================================================

#[derive(Clone)]
pub struct RespondQuestionTool {
    server: Arc<OnceCell<OrchestratorServer>>,
}

impl RespondQuestionTool {
    pub fn new(server: Arc<OnceCell<OrchestratorServer>>) -> Self {
        Self { server }
    }
}

impl Tool for RespondQuestionTool {
    type Input = RespondQuestionInput;
    type Output = RespondQuestionOutput;
    const NAME: &'static str = "respond_question";
    const DESCRIPTION: &'static str = r#"Respond to a question request from an OpenCode session.

After replying, continues monitoring the session and returns when complete or when another interruption is required.

Parameters:
- session_id: Session with pending question
- action: "reply" or "reject"
- answers: Required when action=reply; one list per question"#;

    fn call(
        &self,
        input: Self::Input,
        _ctx: &ToolContext,
    ) -> BoxFuture<'static, Result<Self::Output, ToolError>> {
        let server_cell = Arc::clone(&self.server);
        Box::pin(async move {
            let timer = CallTimer::start();
            let request = input.clone();
            let result: Result<(RespondQuestionOutput, ToolLogMeta), ToolError> = async {
            let server = server_cell
                .get_or_try_init(OrchestratorServer::start_lazy)
                .await
                .map_err(|e| ToolError::Internal(e.to_string()))?;

            let client = server.client();
            let mut pending = client
                .question()
                .list()
                .await
                .map_err(|e| ToolError::Internal(format!("Failed to list questions: {e}")))?;

            let question = if let Some(req_id) = input.question_request_id.as_deref() {
                let idx = pending
                    .iter()
                    .position(|question| question.id == req_id)
                    .ok_or_else(|| {
                        ToolError::InvalidInput(format!(
                            "No pending question found with id '{req_id}'. (session_id='{}')",
                            input.session_id
                        ))
                    })?;

                let question = pending.remove(idx);
                if question.session_id != input.session_id {
                    return Err(ToolError::InvalidInput(format!(
                        "Question request '{req_id}' belongs to session '{}', not '{}'.",
                        question.session_id, input.session_id
                    )));
                }

                question
            } else {
                let mut questions: Vec<_> = pending
                    .into_iter()
                    .filter(|question| question.session_id == input.session_id)
                    .collect();

                match questions.as_slice() {
                    [] => {
                        return Err(ToolError::InvalidInput(format!(
                            "No pending question found for session '{}'. The question may have already been responded to.",
                            input.session_id
                        )));
                    }
                    [_single] => questions.swap_remove(0),
                    multiple => {
                        let ids = multiple
                            .iter()
                            .map(|question| question.id.as_str())
                            .collect::<Vec<_>>()
                            .join(", ");
                        return Err(ToolError::InvalidInput(format!(
                            "Multiple pending questions found for session '{}': {ids}. Please retry with question_request_id (returned by run).",
                            input.session_id
                        )));
                    }
                }
            };

            match input.action {
                QuestionAction::Reply => {
                    if input.answers.is_empty() {
                        return Err(ToolError::InvalidInput(
                            "answers is required when action=reply".into(),
                        ));
                    }

                    client
                        .question()
                        .reply(
                            &question.id,
                            &QuestionReply {
                                answers: input.answers,
                            },
                        )
                        .await
                        .map_err(|e| {
                            ToolError::Internal(format!("Failed to reply to question: {e}"))
                        })?;

                    let outcome = OrchestratorRunTool::new(Arc::clone(&server_cell))
                        .run_impl_outcome(OrchestratorRunInput {
                            session_id: Some(input.session_id),
                            command: None,
                            message: None,
                            wait_for_activity: Some(true),
                        })
                        .await?;
                    Ok((outcome.output, outcome.log_meta))
                }
                QuestionAction::Reject => {
                    client.question().reject(&question.id).await.map_err(|e| {
                        ToolError::Internal(format!("Failed to reject question: {e}"))
                    })?;

                    let outcome = OrchestratorRunTool::new(Arc::clone(&server_cell))
                        .run_impl_outcome(OrchestratorRunInput {
                            session_id: Some(input.session_id),
                            command: None,
                            message: None,
                            wait_for_activity: None,
                        })
                        .await?;
                    Ok((outcome.output, outcome.log_meta))
                }
            }
        }
        .await;

            match result {
                Ok((output, log_meta)) => {
                    log_tool_success(&timer, Self::NAME, &request, &output, log_meta, true);
                    Ok(output)
                }
                Err(error) => {
                    log_tool_error(&timer, Self::NAME, &request, &error);
                    Err(error)
                }
            }
        })
    }
}

// ============================================================================
// Registry builder
// ============================================================================

/// Build the tool registry with all orchestrator tools.
///
/// The server cell is lazily initialized on first tool call.
pub fn build_registry(server: &Arc<OnceCell<OrchestratorServer>>) -> ToolRegistry {
    ToolRegistry::builder()
        .register::<OrchestratorRunTool, ()>(OrchestratorRunTool::new(Arc::clone(server)))
        .register::<ListSessionsTool, ()>(ListSessionsTool::new(Arc::clone(server)))
        .register::<GetSessionStateTool, ()>(GetSessionStateTool::new(Arc::clone(server)))
        .register::<ListCommandsTool, ()>(ListCommandsTool::new(Arc::clone(server)))
        .register::<RespondPermissionTool, ()>(RespondPermissionTool::new(Arc::clone(server)))
        .register::<RespondQuestionTool, ()>(RespondQuestionTool::new(Arc::clone(server)))
        .finish()
}

#[cfg(test)]
mod tests {
    use super::*;
    use agentic_tools_core::Tool;

    #[test]
    fn tool_names_are_short() {
        assert_eq!(<OrchestratorRunTool as Tool>::NAME, "run");
        assert_eq!(<ListSessionsTool as Tool>::NAME, "list_sessions");
        assert_eq!(<GetSessionStateTool as Tool>::NAME, "get_session_state");
        assert_eq!(<ListCommandsTool as Tool>::NAME, "list_commands");
        assert_eq!(<RespondPermissionTool as Tool>::NAME, "respond_permission");
        assert_eq!(<RespondQuestionTool as Tool>::NAME, "respond_question");
    }

    #[test]
    fn last_activity_falls_back_to_session_timestamp_when_messages_are_empty() {
        assert_eq!(get_last_activity_time(&[], Some(1_234)), Some(1_234));
    }
}