Struct WorkerInvocation 

pub struct WorkerInvocation {
    pub token: CapToken,
    pub task_id: TaskId,
    pub attempt: u32,
    pub agent: String,
    pub prompt: String,
    pub sink: Option<Arc<dyn OutputSink>>,
    pub cancel_token: Option<CancellationToken>,
}

Invocation context handed to a Worker fn. Bundles token + task_id + prompt + sink.

The prompt field was added in design intent, folding the old Fn(inv, directive) directive argument into the invocation. The spawner is expected to call engine.fetch_prompt(token, task_id, attempt) in its prep step and inject the snapshot into the invocation (push form). The WorkerFn side may still re-pull if it needs to — for example to fetch the prompt for a different attempt.

The sink field was added in design intent as the formal contract for the spawner’s intake surface. A worker fn can stream intermediate events with things like inv.sink.emit(OutputEvent::Progress { .. }). Child-process spawners (ProcessSpawner, etc.) do not use sink — the child speaks the stdout protocol; InProcSpawner injects one. Even without sink, the WorkerResult returned by the fn is still folded into a Final event on the spawner side, running alongside the older return-value path.

Fields

token: CapToken

Capability token authorizing this attempt.

task_id: TaskId

The task this invocation belongs to.

attempt: u32

Attempt number within the task (used to key output events).

agent: String

Registered agent name the WorkerFn was looked up under.

prompt: String

The prompt/prep snapshot pulled via engine.fetch_prompt, injected here (push form) so the worker fn does not need to call back into the engine for the common case.

sink: Option<Arc<dyn OutputSink>>

Intake: sink the worker fn uses to emit intermediate OutputEvents. Injected by InProcSpawner. None means the sink path is not wired for this invocation.

cancel_token: Option<CancellationToken>

Upstream task cancel token — the clone of cancel_inner generated by InProcSpawner for JoinHandleWorker. Worker fns bridge this to their child futures or their SDK’s shutdown_token, propagating external cancellation all the way down. None — like sink above — means the caller path is not carrying the cancel channel.

Trait Implementations

impl Clone for WorkerInvocation

fn clone(&self) -> WorkerInvocation

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WorkerInvocation

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.