1a81f2cccd
Introduce the `packages/subagent/` group and the abstract subagent seam — an agent delegating to a child agent — as a named-provider registry (`ctx.subagents`), unlike the single-implementation bash seam, so multiple transports (in-process, ACP, future A2A) coexist. This first PR lands the interface, a scripted test backend, and the model-facing tool, validated through the real cordis load path. - dsh-subagent: SubagentService registry + SubagentProvider/SubagentRun vocabulary + subagent/start|end events. Start-time capabilities (outputSchema, depthLimit, toolFilter) are checked pre-start and rejected loud; runtime capabilities (sendMessage, resume) are optional methods on SubagentRun. - dsh-subagent-mock (support): scripted provider for keyless, deterministic tests through the real Loader/export path. - dsh-tool-subagent: the model-facing `subagent` tool, config-bound to one provider; synchronous collect with try/finally dispose, signal->cancel bridging, and non-completed-stop-reason -> isError mapping. - Proposed RFC documenting the seam, the fork-vs-spawn-as-separate-backends decision, own-session isolation, synchronous-collect scope, and the deferral of background/poll/spill to a future unification with bash. - Wire the new group into tsconfigs, build refs, package hierarchy docs, the module graph, and the cordis catalog. RFC: docs/rfc/proposed/feature/2026-06-21-subagent-capability-seam.md
support/ — dev/test/example infrastructure
Packages that exist to serve development, testing, and the examples rather than to ship as product API. They are real workspace packages (typed, tested, under the coverage gate), but they carry lower compatibility expectations: they may change or be removed when the development need behind them does, without the deprecation care a product package would warrant.
| Package | Role | ctx key |
|---|---|---|
invariants/ |
Dev-mode event-contract invariants + session-log freeze | (listens on session/*, agent/*) |
ui-stdio/ |
Minimal stdio (readline) UI plugin: renders agent/* events, feeds stdin lines to the agent |
(drives ctx.agents) |
llm-replay/ |
Record/replay adapter: short-circuits llm/stream from a recorded session JSONL (keyless snapshot tests) |
(listens on llm/stream) |
invariants runs only in dev mode (contract checks, not runtime behavior). ui-stdio and llm-replay were extracted from the examples for reuse and to bring them under the per-file coverage gate; they back the demos and the snapshot test tier. A package graduates OUT of support/ into a product group only when it gains documented product consumers.