Files
deepseek-harness/packages/subagent
Tianyi Cui 3672cd25b4 feat(subprocess): migrate lsp-local, subagent-acp, and the env scrubs onto the seam
Review direction (tianyicui, PR #660): in a stacked PR, change all other
process-running places to use the new service.

- lsp-local: LspConnection spawns through ctx.subprocess (piped protocol
  streams + a no-spill collected stderr tail); its private process-tree
  helpers (POSIX group signalling, Windows taskkill, liveness polling) are
  deleted in favor of the seam's handle verbs, and its buildChildEnv now
  rides scrubbedParentEnv (LSP children also stop inheriting stale DSH_*).
  The plugin injects 'subprocess'; compositions/tests mount
  dsh-subprocess-local.
- subagent-acp: the ACP child spawns through the seam (piped ndjson streams,
  inherited stderr); spawn failure surfaces through done-rejection into the
  same startup race; disposal is handle.dispose with the plugin's configured
  graces. dsh-subagent-subprocess is DELETED — its dispose ladder and scrub
  are the seam's, and the isolated-config-dir helper had no consumer.
- mcp-client, pty-local, sdk-helper: adopt scrubbedParentEnv as the one
  scrub definition (their spawns stay put by ownership: the MCP SDK and
  node-pty own those calls; the SDK wizard runs outside any composition).
- Coverage: per-file 100% over every touched src file, with each v8 ignore
  carrying a platform or contract reason; new suites cover stdio
  dispositions, the dispose ladder tiers, injected-win32 tree semantics,
  waitForExit, settled-kill/terminate no-ops, and spawn-failure disposal.
- Docs: consumer-migration Agent Note (en; zh follows in this PR), seam note
  updated in place, subprocess.md rewritten for the reshaped vocabulary
  (type-equiv re-registered), READMEs and SERVICE_ROLES updated, taskkill
  added to knip ignoreBinaries.
2026-07-26 15:27:59 +08:00
..

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 (no provider; one cleanup effect per run)
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 library with no provider of its own — both depend on it, neither on the other), and the out-of-process subagent-acp backend spawns its child through the subprocess/ seam (the shared credential scrub, tree-scoped teardown, and dispose ladder). Tests replace only the child boundary with package-local fixtures.

The proposal and design rationale: .agents/notes/implemented/feature/2026-06-21-subagent-capability-seam.md.