The auto-advance chain (discuss → plan → execute) was spawning each
subsequent phase as a Task(subagent_type="general-purpose"), creating
3-4 levels of nested agent sessions. At that nesting depth, the
Claude Code runtime hits resource limits or stdio contention, causing
the execute-phase to freeze or attempt to shell out to `claude` as a
subprocess (which is explicitly blocked).
The fix replaces Task spawns with Skill invocations for phase
transitions:
- discuss-phase auto-advance: Skill("gsd:plan-phase") instead of
Task(general-purpose)
- plan-phase auto-advance: Skill("gsd:execute-phase") instead of
Task(general-purpose)
The Skill tool runs in the same process context as the caller,
keeping the entire auto-advance chain flat at a single nesting level.
Each phase still spawns its own worker agents (gsd-executor,
gsd-planner, etc.) as Tasks, but the orchestration chain itself
no longer creates unnecessary depth.
Closes#686
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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