Resume fails when subagents use parallel tool calls due to Claude Code
serialization bug (consecutive assistant entries with same message ID).
Solution: Subagents return structured checkpoint state, orchestrator
spawns fresh agent with continuation-prompt template instead of resuming.
New files:
- templates/checkpoint-return.md: Structured format with completed tasks table
- templates/continuation-prompt.md: Template for spawning continuation agent
Updated:
- templates/subagent-task-prompt.md: Reference checkpoint-return, remove resume language
- workflows/execute-phase.md: Replace Task(resume=id) with fresh agent spawn
- workflows/execute-plan.md: Update checkpoint_return_for_orchestrator step
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- execute-plan.md: Add checkpoint_return_for_orchestrator step
explaining how to return at checkpoints when spawned via Task tool
- subagent-task-prompt.md: Add checkpoint_behavior and completion_format
sections to guide agents on returning for checkpoints
Tested: Task resume works - agent pauses at checkpoint, returns with
details, orchestrator presents to user, resumes with Task(resume=id).
Parallel agents each get unique agent_id for independent resume.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>