Subtask Creation — Engineer's Delegation Skill

You're implementing a feature. You discover: there's no documentation for this API. Or: this touches authentication and needs security review. Or: the test coverage for this module is below 50%. These aren't YOUR tasks — they're tasks for other agents. Create subtasks.

When to Create Subtasks

Discovery	Target Agent	Subtask Type
Missing documentation	technical-writer	docs task
Security concern in code you're touching	devsecops-expert	security review
Test gap found during implementation	qa-engineer	test task
Infrastructure need (deployment, CI)	devops	infra task
UX concern in user-facing change	ux-designer	UX review
Design question needing architectural input	architect	design task

fleet_task_create vs fleet_request_input

fleet_task_create — Creates a full task on the board. Use when:

• The work is substantial (not a quick question)
• The other agent needs their own task lifecycle (stages, review)
• You want it tracked in the sprint

fleet_request_input — Creates a lightweight contribution request. Use when:

• You just need a quick answer or input
• The other agent can respond in one heartbeat cycle
• No separate task lifecycle needed

How to Create a Proper Subtask

Follow the PM's triage discipline — set ALL fields:

fleet_task_create(
    title="Document: fleet_contribute API endpoint",
    description="The fleet_contribute MCP tool has no user-facing documentation. "
                "Need: endpoint reference, parameters, example usage, error codes.",
    agent_name="technical-writer",
    task_type="subtask",
    parent_task="your-task-id",    # Links to your task
    task_stage="reasoning",         # Writer will plan before writing
    task_readiness=80,
    story_points=2,
    delivery_phase="mvp",           # Match your task's phase
)

The Fields That Matter

Field	Why It Matters
agent_name	Routes to the right specialist
parent_task	Links child to parent — fleet-ops reviews the relationship
task_type="subtask"	Skips contribution requirements (subtasks are small)
task_stage	Set based on clarity — if you know exactly what's needed, set to reasoning or work
story_points	Helps PM with sprint capacity
delivery_phase	Match your parent task's phase

The Cascade Depth Limit

The fleet has a maximum cascade depth of 3. Your subtask can have sub-subtasks, but no deeper:

Epic (depth 0)
├── Story (depth 1)
│   ├── Task (depth 2)
│   │   ├── Subtask (depth 3) ← maximum
│   │   └── Subtask (depth 3)
│   └── Task (depth 2)

If fleet_task_create with a parent at depth 3 is called, it will be blocked with a cascade error.

After Creating

1. Post a comment on your own task noting the subtask: "Created subtask for docs: {task_id}"
2. Continue your work — don't wait for the subtask unless it blocks you
3. If the subtask IS blocking (you need security clearance before proceeding): fleet_pause(reason="Waiting for security review subtask {id}")

What NOT to Create Subtasks For

• Things you should do yourself — writing your own tests, writing inline comments, running linters
• Questions you can answer — don't create a task just to ask "how does this work?" Use code-explorer sub-agent.
• PM work — don't create task management subtasks. PM handles triage and assignment.
• Scope expansion — if you're discovering new features during implementation, that's scope creep. fleet_escalate to PM/PO.