25eccdaedc
Address four findings from the first Codex review round: - Contain subagent/start|end listener throws (emitContainedStart/End): a thrown lifecycle listener could escape SubagentService.start() before the caller received the live run to dispose it (a leaked child), and a thrown subagent/end listener could surface as an unhandled rejection on the detached result-settle hook. Both emits now log-and-contain, mirroring the agent registry's agent/created|disposed containment. - Make the model-facing tool name configurable (Config.toolName, default subagent). The docs say to load dsh-tool-subagent once per provider to expose multiple transports, but the hardcoded name made the second load throw a duplicate-tool-name error; a distinct toolName per load is now required and documented. - Reach the per-file 100% coverage gate: tests for the subagent/end error branch, lifecycle-listener containment, every stopReasonError arm + the merge-extensible default, the multi-provider toolName path, agentOptions forwarding, and the direct-apply schema-bypass fallbacks. - Document the seam vocabulary in docs/core-data-structures/subagent.md with verbatim type-equiv blocks + manifest entries, and link it from core.md (a brand-new core/seam type the doc-sync gate cannot detect on its own).
@deepseek-ai/dsh-tool-subagent
The model-facing subagent tool: delegate a self-contained task to a child agent and return its final output. Pure schema + lifecycle shaping over the ctx.subagents provider registry — an in-process, ACP, or future A2A backend swaps in without changing what the model sees.
Provider selection is config, not model-facing
This plugin binds to exactly one provider (Config.provider). The model sees only { description, prompt } — there is no provider/type parameter in the schema. To expose more than one transport, load the plugin more than once, each bound to a different provider and a distinct toolName (the tool registry rejects a duplicate name, so a second load that kept the default subagent name would throw). Keeping selection in config (not the schema) is the deliberate split: the service holds a multi-provider registry; the tool picks one.
| Config key | Meaning |
|---|---|
provider (required) |
The ctx.subagents provider name to start runs on (spawn, fork, acp, …). |
toolName |
The model-facing tool name to register (default subagent). Set a distinct value per load when exposing multiple providers, e.g. subagent + subagent_acp. |
agentOptions |
Default per-child { model?, systemPrompt? } applied to every spawned child. |
Lifecycle (synchronous collect)
execute starts a run on the configured provider and awaits run.result inside a try/finally that always dispose()s the run — the owned child agent/session is torn down on every path (success, error, abort), never leaked. The tool's abort signal (exec.signal) is bridged to run.cancel(). A non-completed stop reason (aborted/error/max-tokens/refusal) maps to an isError tool result rather than returning partial output as success.
Background / poll collection is deferred (see the RFC); this cut blocks the parent turn until the child finishes.