Tianyi Cui
706691a7df
Codex convergence round 1 on the review-response commits: agent()'s post-acquire window was real and unguarded. `await acquireSlot()` yields at least one microtask tick even when a slot is free (and a queued waiter resumes a tick after its release), so a cancel() landing in that tick let the continuation start a child carrying an ALREADY-aborted signal — the in-code comment claimed the window could not exist. A provider that subscribes only to future abort events (the test stub; the seam does not promise pre-aborted-signal handling) would never settle such a child, leaking it until the dispose grace abandoned the run, and a backend that misses the pre-aborted signal would burn a full model turn after the user cancelled. agent() now re-checks isCancelled() immediately after the acquire (inside the slot-owning try, so the finally still releases), making every post-cancel path reject before subagents.start. New deterministic regression: cancel() in the same synchronous frame as start() lands in the free-slot await tick — the run settles cancelled with ZERO children started (previously: one leaked child and a grace-delayed settle). The raced-release test's comment now states what it actually pins (the queued-waiter rejection path). Also aligns the RFC's auto-concurrency formula with the code (min(16, max(1, availableParallelism() - 2))).
workflow/ — dynamic-workflow capability family
The workflow seam: a model-written JavaScript orchestration script that fans out subagents at scale (phases, structured per-agent results, concurrency caps), modeled on Claude Code's dynamic workflows. A capability seam (see capability seams) in the bash shape: ONE engine implementation per context registers as ctx.workflows; the model-facing tool consumes it.
| Package | Role | ctx key |
|---|---|---|
workflow/ |
Abstract workflow seam: service base class + run vocabulary + workflow/* events |
ctx.workflows |
workflow-vm/ |
In-process node:vm engine: parses the script, injects the hooks, drives ctx.subagents |
(provides ctx.workflows) |
tool-workflow/ |
Model-facing workflow tool over ctx.workflows |
(registers on ctx.tools) |
The interface lives at workflow/workflow/. The engine's agent() hook rides the subagent seam (any registered provider; the shipped examples use spawn), and agent({ schema }) rides the structured-output support the in-process backends implement. The seam split exists for engine hardening: node:vm is in-process and cannot kill a pathological synchronous spin — a worker-thread or isolated-vm engine swaps in behind the same interface if that ever matters.
The proposal, decisions, and deferred work: docs/rfc/implemented/feature/2026-07-05-dynamic-workflows.md.