Six verified A-findings from the code-stage review, each with a regression test: - parallel()/pipeline() resolved to HOST arrays inside the vm realm, exposing host Array.prototype to scripts; combinator results are now realm-built (in-realm Array.from bound at context setup). - materializeFromRealm ran proxy traps (ownKeys/getOwnPropertyDescriptor/ getPrototypeOf) during the descriptor walk — realm code on the host stack, outside the vm timeout, escaping as raw errors; proxies (root, nested, and in the prototype position) are now rejected trap-free via util.types.isProxy before any inspection. - an already-aborted signal or an immediate cancel() no longer reports 'completed' for a hook-free script: drive() checks cancellation before running the body and again when the script settles. - dispose() now waits (bounded by disposeGraceMs) for stray agent() children to FINISH disposing, not just for the script to settle: every agent() call is tracked and quiesce() drains the in-flight set. - workflow/* event payloads were live mutable aliases shared across emissions; emitWorkflowEvent now hands each listener its own structural clone. - the structured-output turn-continuation veto is now prepend: true, so an earlier-registered force-continue listener cannot short-circuit it. Docs updated in the same change (READMEs, core-data-structures/workflow.md, the dynamic-workflows RFC, regenerated cordis catalogs).
subagent/ — subagent capability family
The subagent seam: an agent delegating work to a child agent. Like the bash and llm families this is a capability seam (see capability seams) — but with one defining difference: multiple provider implementations coexist in one context, registered by name, rather than the single-implementation bash shape. The registry mirrors the LLM adapter registry.
| Package | Role | ctx key |
|---|---|---|
subagent/ |
Abstract subagent seam: named-provider registry + vocabulary | ctx.subagents |
subagent-inprocess/ |
Shared in-process run driver (pure lib; registers nothing) | — |
subagent-spawn/ |
In-process backend: a fresh child agent | (registers on ctx.subagents) |
subagent-fork/ |
In-process backend: a child seeded with the parent's completed-turn prefix | (registers on ctx.subagents) |
subagent-acp/ |
Out-of-process backend: a child agent in a spawned subprocess, driven over ACP | (registers on ctx.subagents) |
tool-subagent/ |
Model-facing subagent delegation tool over ctx.subagents |
(registers on ctx.tools) |
The interface lives at subagent/subagent/. The in-process subagent-spawn / subagent-fork backends share the subagent-inprocess driver (a pure library — both depend on it, neither on the other), and the out-of-process subagent-acp backend ships alongside them here; the test-only dsh-subagent-mock (in support) is separate. All product packages except the mock.
The proposal and design rationale: docs/rfc/implemented/feature/2026-06-21-subagent-capability-seam.md.