deepseek-harness/packages/support/subagent-mock/README.md

@deepseek-ai/dsh-subagent-mock

A scripted SubagentProvider for testing the subagent seam without a model or a real child agent — the subagent analog of dsh-llm-replay.

It lets a test drive ctx.subagents and the model-facing dsh-tool-subagent through the real cordis Loader / export path, exercising provider registration, start-time capability validation, the run lifecycle (result / cancel / dispose), and the structured-output branch — all deterministically and keylessly.

Model Experience

Context surface	What the model sees	Token effect
Deterministic test result	No child model runs. When exercised through dsh-tool-subagent, the parent sees the mock provider's configured reply or stop-reason error, and structured tests receive the configured object.	Zero child-model tokens. Only the scripted final result is added to the parent test history.

Usage

Load it as a plugin (functional shape: name/inject/Config/apply, no default). Config (all optional):

Key	Default	Meaning
name	mock	Registry name to register the provider under.
reply	mock subagent reply	The scripted child's final answer text.
stopReason	completed	The stop reason result settles with.
capabilities	all true	Which start-time capabilities (outputSchema/depthLimit/toolFilter/persona) the provider advertises.
inheritsParentContext	false	The context contract to declare; true exercises the fork-shaped tool wording in consumer tests.
structured	{ reply }	Structured value surfaced when a request carries an outputSchema and the capability is on.

A cancel() issued before result settles flips the stop reason to aborted, so the cancellation path is observable.

Known Limitations and Deferred Work

• Scripted provider only — it does not run a model, create a child agent, or exercise real prompt/tool-loop behavior.
• One immediate synthetic outcome per run — it models no multi-turn, streaming, readiness delay, or subprocess transport behavior.
• dispose() is a no-op — lifecycle tests using it prove consumer control flow, not resource teardown or quiescence of a real backend.