src/engine/bare/dispatch.rs

This file runs your per-call pipeline, both dispatch modes, and the recovery loop. It runs about 1,950 lines with tests.

Key items

dispatch_tools is sequential, checking cancel between calls, or parallel.

Parallel mode plans ToolDependencyGraph waves from is_safe_for_concurrent_execution plus resource_key conflicts, clamps them with a semaphore, returns results in input order, and discards resolved siblings on a hard error.

execute_tool_call is your full per-attempt pipeline. It starts with the pre observer, then hooks, where an Ask with a resolver parks the run through the ask channel (0.4.0).

Next comes pre-detection, a pure read where a stop becomes a hard error, then the breaker gate, then the biased cancel-vs-dispatch.

Then post-detection, which is the single write point, then the post observer, then gate-decision emission through on_gate_decision, ordered pre, gate, post (0.4.0).

The tail is post hooks, health, memory honoring records_trajectory(), and recovery.

dispatch_tool uses the pipeline first if configured, else the registry, and every call is panic-isolated with catch_unwind. An unknown tool becomes a soft error listing available names.

The pipeline core in middleware/tool_call.rs checks the cancel signal before invoking the tool (0.3.2), so a pre-cancelled call never starts, deterministically rather than by select! branch luck.

recovery_wait_or_return reflects, decides, and backs off cancel-aware for you, and the attempt > 5 ceiling raises ToolRecoveryExhausted.

apply_correction_if_present swaps input or tool, and failed corrections are logged and dropped.

record_tool_memory writes your trajectory entries, truncated at 500 characters, after successful calls only.

Behavior notes

Side effects, meaning observers, hooks, detection, and health, fire per attempt in both modes.

Your engine stamps tool_call_id after the pipeline returns, so middleware ids are advisory.

The breaker gate keys on the requested name, while health_key records under the resolved name.

Deep dive: Tool dispatch.