Subagent orchestration

Subagent Orchestration

Use subagents as a harness, not as a reflex. The goal is higher signal per token, not more parallelism.

When to Use

Use this skill when:

• The work can be split into independent read-heavy tasks
• Multiple review lenses would improve confidence
• One bounded implementer can own the write path while others explore or review
• The workflow will cross stages and needs an explicit handoff contract

Do not use this skill when:

• A single agent can complete the task without context pressure
• Multiple subagents would edit the same files or shared state
• The host cannot support the needed delegation model safely

Default Orchestration Policy

Fan out only when the delegated scopes are independent and at least one of these is also true:

• The task is non-trivial or cross-cutting
• Independent review would materially change confidence

1. Parallelize read-heavy work first.
2. Keep write ownership narrow.
3. Define a handoff contract before multi-stage delegated work starts.
4. Require synthesis after any fan-out.
5. Require evidence in every subagent return.
6. Keep review and research subagents read-only with the minimum tools they need.
7. Keep lightweight workers on narrow tasks and reserve final judgment for the parent.
8. Escalate risky changes to human review.

Default budget:

• Research split: 2-4 subagents
• Review fan-out: 3 reviewers
• Implementation: 1 writer
• Delegation rounds: one research split and one review fan-out per user request or change objective unless the human asks for another scoped pass

Collapse back to one agent when:

• Tasks share files or state
• Findings become repetitive
• Coordination cost exceeds likely speedup

Mandatory human gate:

• Stop and ask before auth changes, public API changes, migrations, destructive operations, external contract changes, or overlapping or unclear concurrent writes.
• Stop and ask before changes that affect shared behavior, shared tests, or more than one owned file group unless ownership is explicitly disjoint and low risk.
• If risk is unclear, default to stop and ask.

Handoff contract minimum:

• Scope and owner
• Acceptance criteria
• Evidence expected on return
• Next-step handoff note

Host Compatibility

Use the host-specific limits in references/host-compatibility-and-limits.md before delegating. Do not assume every host supports the same depth, communication model, or permission model.

Required Patterns

Use these references as needed:

• references/orchestration-patterns.md
• references/handoff-contracts.md
• references/review-fanout-and-synthesis.md
• references/anti-patterns.md

Non-Negotiable Rules

• Never run overlapping multi-writer edits without hard ownership boundaries.
• Never hand work to the next stage without a readable handoff artifact.
• Never accept summary-only subagent output without evidence.
• Never fan out reviewers and skip synthesis.
• Never give edit-capable permissions to read-only review or research work.
• Never keep adding subagents when the output quality is already flattening.