Files
deepseek-harness/packages/subagent
Tianyi Cui d1b52a063b fix review findings: own-property and plain-JSON discipline in the schema subset
Three Codex findings on json-schema.ts, one discipline:

- required-declared and every value check now use Object.hasOwn — 'in' let
  inherited names (toString) satisfy required, dodge additionalProperties:
  false, and validate a declared property against the value's prototype
  member instead of a carried one
- isObjectLike now means PLAIN JSON object (proto chain of at most one link,
  realm-agnostic): a Date annotation or a Map-as-properties no longer passes
  structurally and serializes lossily — they fail loud as subset violations
- startInProcessRun asserts BEFORE the defensive structuredClone, so a
  hostile schema fails as OutputSchemaError, never a raw DataCloneError

Also the type-equiv catalog gap: tools.md gains the structured-output subset
vocabulary (4 blocks) with matching manifest entries. The driver index also
drops the runtime internals from its public re-export (runs acquire it
internally; no external consumer remains — see the following commit).
2026-07-07 21:07:54 +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 (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.