dd2f37b80f
Review follow-up: the blanket 10s default correctly targets worker-thread cold-start races (starting, first-script-line, async child-registration messages — genuinely CPU-bound under CI contention), but four waits assert something different — that the HOST reacted PROMPTLY to an event that already happened (a settled result, an observed worker death). Those had no cold-start left to wait on, so the generous default just widened the window a real regression could hide in. Verified by injecting a 6s delay into the settle-reap's abort call: the un-overridden helper's test still passed in ~6s. The same mutation now fails in ~1s with the explicit 1000ms override restored on all four sites (the abort-on-settle test's own assertion, the two worker-death cancel/dispose reap checks, and the dispose-ack-race check). The other 12 waits keep the 10s default — they run BEFORE a result is awaited, waiting on the worker to actually start rather than on a host reaction. Doc comment corrected to describe the split instead of claiming every wait is a cold-start race.
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-workerthread/ |
node:worker_threads engine: one worker per run; the script's vm context lives inside the worker, agent() bridges to ctx.subagents over the message port |
(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 worker thread isolates the SCRIPT — the host never blocks on it, and a cancelled run's post-grace termination is real — but it is NOT a security boundary; an isolated-vm/separate-process engine (actual sandboxing) 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.