Struct HarnessActionHost 

pub struct HarnessActionHost { /* private fields */ }

The RuntimeActionHost impl over an AgentHarness. Built once per session in crate::session::build — constructed empty before extension load (the harness doesn’t exist yet), then filled via set_harness once AgentHarness::create succeeds. Carried inside the [ActionBridge] as Arc<dyn RuntimeActionHost>.

runtime is captured at build time so the bridge can spawn dispatch from any thread; the impl’s async methods run ON that runtime (they are spawned by the trampoline), so they may freely await.

Implementations

impl HarnessActionHost

pub fn new_empty( catalog: Vec<Model>, cwd: PathBuf, runtime: Handle, cli_flags: BTreeMap<String, Value>, tool_context: ToolCallContext, ) -> (Self, Arc<OnceLock<Arc<AgentHarness>>>)

Build an empty host (no harness yet). The runtime is the handle the bridge captured (kept only so the impl can name it for future direct-spawn needs; the trampoline already spawns on the bridge’s runtime). Call set_harness once the harness is created. Returns (host, harness_cell) where harness_cell is the shared OnceLock the caller fills.

pub fn set_harness( cell: &Arc<OnceLock<Arc<AgentHarness>>>, harness: Arc<AgentHarness>, )

Fill the harness cell. Call exactly once, immediately after AgentHarness::create succeeds. Returns the host (for fluent chaining) — the caller already holds the Arc<dyn RuntimeActionHost> from construction; this just populates the cell that host reads.

Trait Implementations

impl RuntimeActionHost for HarnessActionHost

fn get_cli_flag<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

GetCliFlag — read a parsed extension CLI flag. Args are {"name":"flag"} and the result is {"value": <bool|string|null>}.

fn send_message<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SendMessage — drive a full agent run from an assistant/user message.

fn send_user_message<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SendUserMessage — drive a run from a user-text message.

fn append_entry<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

AppendEntry — append a raw entry to the session transcript (no run).

fn get_session_branch<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

GetSessionBranch — current main branch entries, oldest-first.

fn set_session_name<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SetSessionName — set the session’s display name.

fn get_active_tools<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

GetActiveTools — the active tool-name list.

fn set_active_tools<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SetActiveTools — replace the active tool-name list.

fn set_model<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SetModel — switch the active model (by id; host resolves to a Model).

fn get_thinking_level<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

GetThinkingLevel — the current thinking level.

fn set_thinking_level<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SetThinkingLevel — set the thinking level.

fn compact<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Compact — compact the session transcript.

fn get_system_prompt<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

GetSystemPrompt — the live composed system prompt.

fn new_session<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

NewSession — start a fresh session and switch to it.

fn fork<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Fork — fork the current session and switch to the fork.

fn navigate_tree<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

NavigateTree — navigate/rewind the session tree.

fn switch_session<'life0, 'async_trait>( &'life0 self, args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

SwitchSession — hot-switch to an existing session by id.

fn reload<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Reload — re-run extension discovery + Part-A resource loaders (a CLI concern; the host impl wires it to the ActionBridge.reload callback in B5d — until then this returns an “unsupported” error string).

fn ui_dialog<'life0, 'async_trait>( &'life0 self, _args: Value, ) -> Pin<Box<dyn Future<Output = Result<Value, String>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: 'async_trait,

UiDialog fallback for hosts that do not install an interactive mailbox. The default is deliberately an error so headless runs cannot accidentally report a fabricated user answer.