74502fa8c2
Carved out of #170 per review feedback — the foundation the workflow tool builds on, now standing alone on master: - dsh-tools: the structured-output JSON Schema subset (StructuredOutputSchema, assertSupportedOutputSchema, validateStructuredValue) — rejects loud outside the enforced subset, listing every violation - dsh-subagent: SubagentStartRequest.outputSchema / SubagentResult.structured become a real capability; the service rejects a schema'd request whose provider lacks it - dsh-subagent-inprocess: the shared structured runtime — one global structured_output capture tool, a prepend final-assembly listener that strips the placeholder for plain agents and swaps in the run's own schema (plus the calling instruction as a trailing section) for structured children, an agent/turn-continuation veto once captured, and the capture/nudge loop in the run driver (structuredNudgeRetries, cancellation honored mid-nudge); lifetime refcounted by backends and live runs - subagent-spawn / subagent-fork flip outputSchema: true One deliberate divergence from the #170 revision: the backends do NOT add 'tools' to their plugin inject. Doing so deferred their apply past the todo plugin, and the delegation tool mirrors provider lifecycle — so the model-visible tool order of every existing prompt changed, invalidating every recorded snapshot fixture. The runtime now gates its capture-tool registration on tools availability itself (sync when live, a scoped inject fiber when the Loader starts the backend first), keeping this PR byte-invisible to existing transcripts: all 35 snapshot scenarios pass against master's fixtures unchanged.
@deepseek-ai/dsh-subagent-fork
The in-process fork subagent backend: a SubagentProvider that runs each child as a child Agent seeded with a prefix of the parent's session log — so the child inherits the parent's conversation context instead of starting fresh. Shares the run driver (startInProcessRun) with dsh-subagent-spawn; the only difference is the seed.
The seed boundary (the crux)
At the moment a subagent tool's execute runs, the parent's CURRENT turn is open and unbalanced: the log holds the assistant/message carrying this spawn's tool-call and the dangling tool/call with no tool/result yet. Seeding that raw prefix would give the child an open turn that the session constructor and the dev-mode invariants replay reject.
So the fork seeds only the balanced completed-turn prefix — the parent's log up to and including its last turn/end, excluding the in-flight turn entirely (completedTurnPrefix). Because the live log keeps seq === index, the slice is contiguous-from-0 and a valid seed. A parent on its very first (not-yet-complete) turn forks an empty seed — i.e. effectively a fresh child.
The seam this rides on: CreateAgentOptions.seed (added on dsh-agent, threaded through AgentLoop.createAgent → ctx.sessions.prepare({ seed })), the same primitive resume uses.
Capabilities
{ outputSchema: true, depthLimit: true, toolFilter: false } — identical to spawn (the depth/model/structured-output behavior is the shared driver's).
Config
| Key | Meaning |
|---|---|
providerName |
Registry name on ctx.subagents (default fork). |
structuredNudgeRetries |
How many times a structured run re-prompts a child that finished cleanly without calling structured_output (default 1). |
See dsh-subagent-spawn for the run lifecycle, model inheritance, and depth tracking — all shared.