---
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module: "subagent-patterns"
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generatedAt: "2026-08-20T06:54:23.199Z"
---
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# Subagent Patterns

Subagent dispatch methodology: task decomposition, spec-driven delegation, pass-paths-not-contents, two-stage review (spec compliance then code quality), parallel coordination, concurrency/rate-limit throttling for fan-outs, and skill invocation modes.

- Category: workflow
- Status: stable
- Tags: subagents, delegation, parallel, coordination, review, agents, rate-limits, concurrency
- Dependencies: none
- Presets: cloud-agent, full, team
- Context cost: ~5911 tokens (always-loaded rule files)
- Last updated: 2026-08-04T09:16:14-04:00
- Available as a native plugin marketplace entry

## README

# subagent-patterns

Subagent dispatch methodology for effective task delegation.

## What It Does

Installs rules covering subagent coordination:

- **When to use subagents** - 3+ independent tasks, parallel research, context protection
- **Task decomposition** - Write specs with objective, context, constraints, deliverable
- **Right-sizing** - Each task completable in one pass, independently verifiable, scoped to one concern
- **Dispatch patterns** - Parallel research, parallel implementation, dependency ordering
- **Pass paths, not contents** - Give subagents file paths to read, not pasted file bodies
- **Two-stage review** - Stage 1: spec compliance (gates Stage 2), Stage 2: code quality
- **Coordination rules** - No shared state, aggregate results, report failures
- **Completion status protocol** - DONE / DONE_WITH_CONCERNS / BLOCKED / NEEDS_CONTEXT
- **Skill invocation modes** - interactive / autofix / report-only / headless for composable skill calls
- **Reusable agent prompt templates** - `implementer`, `spec-compliance-reviewer`, `code-quality-reviewer` for consistent dispatch and review
- **Concurrency and rate limits** - Cap simultaneous heavy agents (4, never >5), launch fan-outs in waves, default to cheaper models / lower effort, and recover from server-side 429 throttles - covers both the Workflow tool and direct parallel Agent dispatch

## Manual Installation

```bash
# Global (all projects)
mkdir -p ~/.claude/rules
cp rules/subagent-patterns.md ~/.claude/rules/subagent-patterns.md
cp rules/concurrency-and-rate-limits.md ~/.claude/rules/concurrency-and-rate-limits.md
mkdir -p ~/.claude/agents
cp agents/implementer.md ~/.claude/agents/implementer.md
cp agents/spec-compliance-reviewer.md ~/.claude/agents/spec-compliance-reviewer.md
cp agents/code-quality-reviewer.md ~/.claude/agents/code-quality-reviewer.md

# Hooks
mkdir -p ~/.claude/hooks
cp hooks/subagent-stop-check.py ~/.claude/hooks/subagent-stop-check.py
cp hooks/task-completed-check.py ~/.claude/hooks/task-completed-check.py
chmod +x ~/.claude/hooks/subagent-stop-check.py
chmod +x ~/.claude/hooks/task-completed-check.py

# Merge settings.partial.json into ~/.claude/settings.json
# Add the relevant hook wiring from settings.partial.json
```

## Files

| File | Description |
|------|-------------|
| `rules/subagent-patterns.md` | Subagent decomposition, dispatch patterns, and review methodology |
| `rules/concurrency-and-rate-limits.md` | Caps heavy-agent fan-out concurrency, wave sizing, and 429-throttle recovery for the Workflow tool and direct parallel Agent dispatch |
| `agents/implementer.md` | Reusable prompt template for implementer subagents - enforces scope discipline and four-state status |
| `agents/spec-compliance-reviewer.md` | Stage 1 reviewer - adversarial stance, verifies deliverables and constraints independently of the implementer's self-report |
| `agents/code-quality-reviewer.md` | Stage 2 reviewer - refuses to run unless Stage 1 returned DONE; checks project patterns, edge cases, simplicity |
| `hooks/subagent-stop-check.py` | SubagentStop hook that verifies subagent returns a valid four-state status before returning control |
| `hooks/task-completed-check.py` | PostToolUse hook that nudges the dispatcher to verify subagent artifacts before accepting DONE |
| `settings.partial.json` | Hook wiring configuration to merge into settings.json |


## Files

### rule

#### rules/subagent-patterns.md

````
# Subagent Patterns

Methodology for decomposing work and delegating to subagents (Agent tool) effectively.

## When to Use Subagents

Use subagents when:
- A task has 3+ independent subtasks that can run in parallel
- Research needs to happen across multiple files or systems simultaneously
- The main context window would be polluted by verbose intermediate results
- Multiple issues or PRs need to be completed independently

Do NOT use subagents for:
- Simple file reads or searches (use Glob/Grep/Read directly)
- Sequential tasks where each step depends on the previous result
- Tasks that require maintaining conversation context with the user

## Task Decomposition

### Write a Spec for Each Subtask

Before dispatching a subagent, define:

1. **Objective** - one clear sentence describing the expected outcome
2. **Context** - relevant file paths, function names, or background the agent needs
3. **Constraints** - patterns to follow, files not to modify, libraries not to add
4. **Deliverable** - what the agent should return (code changes, research summary, test results)

Bad: "Fix the auth bug"
Good: "In /src/auth/session.ts, the refreshToken function silently swallows errors on line 47. Add proper error propagation and a test in /tests/auth/session.test.ts that verifies refresh failures are surfaced."

### Right-Size the Work

Each subagent task should be:
- **Completable in one pass** - the agent should not need to ask clarifying questions
- **Independently verifiable** - the result can be checked without running other tasks first
- **Scoped to one concern** - one bug fix, one feature, one research question

## Dispatch Patterns

### Parallel Research

When exploring a question that spans multiple areas:

```
Agent 1: "Search for all usages of TokenManager in src/ and list the call sites"
Agent 2: "Read the auth middleware in src/middleware/auth.ts and summarize the token validation flow"
Agent 3: "Check the test coverage for src/auth/ - list tested and untested functions"
```

### Parallel Implementation

When implementing changes across independent files:

```
Agent 1: "Add input validation to the /api/users endpoint in src/routes/users.ts"
Agent 2: "Add input validation to the /api/posts endpoint in src/routes/posts.ts"
Agent 3: "Write shared validation helpers in src/utils/validate.ts"
```

Note: If agents share dependencies (Agent 3's output is needed by 1 and 2), run the dependency first, then the dependents in parallel.

### Isolate Parallel Implementers in Worktrees

When parallel implementers modify files, give each its own **git worktree** (`isolation: "worktree"`) — the default isolation for parallel sub-agent delegation on one machine. Each worktree has its own index and HEAD, so agents editing, building, and committing at the same time never collide; this is the structural enforcement of the "no shared state" coordination rule below. Worktrees are ephemeral — created per unit, removed when the unit's PR merges, with `/worktree-sweep` as the orphan backstop. Do **not** spin up extra permanent clones just for parallelism; reserve clones for long-lived independent agents, per-branch dev-server ports, hook-driven per-branch `tracking.csv`, or cross-machine dispatch. **Teardown is mandatory**: a worktree an agent built in does not auto-remove, and forgetting to remove merged worktrees is what filled 237 GB on one repo (2026-07-13). See `git-worktrees.md` and `multi-agent.md`.

**Throttle heavy fan-outs.** Launching too many heavy agents at once (whether via the Workflow tool's `parallel()`/`pipeline()` or multiple Agent calls in one message) trips a server-side 429 throttle that fails the entire burst. Cap simultaneous heavy agents to 4 (never exceed 5), launch in waves, and default fan-out agents to cheaper models / lower effort unless thoroughness is explicitly requested. See `concurrency-and-rate-limits.md` for the defaults, the exact error, and the throttled-mid-run recovery procedure.

## Pass Paths, Not Contents

When a subagent needs access to reference material, pass **file paths**, not file contents. The orchestrator should not pre-read files and splice their text into the prompt. It should tell the subagent where the files are and let the subagent read what it actually needs.

Why this matters:
- **No wasted reads** - the orchestrator does not spend tokens loading files that the subagent may skim or skip
- **Prompt does not balloon** - adding a tenth reference path costs one line, not a thousand tokens of file content
- **Subagent keeps agency** - it decides which files are relevant, in what order, and can search within them; pasted content is a snapshot, not a live reference
- **Works at scale** - ten reference files do not grow the dispatch prompt linearly

Bad: "Here is the content of src/auth/session.ts: [2000 lines pasted]. Here is tests/auth.test.ts: [800 lines pasted]. Find the bug."

Good: "The relevant files are src/auth/session.ts and tests/auth.test.ts. Also check any other file matching src/auth/**. Find the bug."

Template:

```
Task: {one-sentence objective}

Reference files (read as needed):
- {path 1}
- {path 2}
- Search pattern: {glob or grep query if the set is open-ended}

Deliverable: {what to return}
```

The only exception: inline a small excerpt (10-30 lines) when the subagent needs to match a specific passage and searching for it would be ambiguous. Paste the snippet with its file path as a locator, not as a replacement for the file.

## Two-Stage Review

After subagent results come back, review in two passes. **Order matters: Stage 1 gates Stage 2.** Running code-quality review on a scope-creeping or deliverable-incomplete implementation wastes effort polishing code that will be reverted or re-dispatched.

### Fresh Context: Reviewers Do Not Inherit the Implementer's Rationale

Both review stages run in **fresh context**. A reviewer judges the change against the spec and the artifact, not against the implementer's explanation of why they did it that way. A reviewer who reads "I chose X over Y because…" grades the *defense* of the change, not the change - and that inflates sign-off. This is the same integrity property Argus enforces by never showing its judge the diff-author's reasoning.

Pass each reviewer ONLY:

- the **spec** (objective, context, constraints, deliverable) - the target
- the **diff or changed-file paths** - the artifact
- fresh **build/test output** - the deterministic evidence

Do NOT pass the implementer's conversation, working notes, or chain-of-thought as grounding. The one nuance for Stage 1: the implementer's `DONE` report is an **audit target**, not grounding - the reviewer reads it to check the claims against the diff, never to be persuaded by it. Stage 2 does not need the report at all.

### Results Stay in Files, Not in the Reply

Each reviewer writes its structured findings (the four-state status plus its itemized checks) to a file the caller named, and replies with only that path plus a terminal line. The caller routes on the artifact it reads from disk, not on a prose summary in the chat. This mirrors Argus: the dispatcher trusts the written result, never a narrative that cannot be re-read. If the artifact is missing or unparseable, treat the reviewer as failed - do not reconstruct its verdict from the reply.

### Stage 1: Spec Compliance

- Did the agent do what was asked?
- Are all deliverables present?
- Were constraints respected?
- Did the agent creep beyond the spec (touching files, helpers, or adjacent bugs it was not asked to)?

If Stage 1 fails, re-dispatch the implementer with specific feedback. Do NOT proceed to Stage 2.

### Stage 2: Code Quality

- Does the code follow project patterns?
- Are there edge cases not handled?
- Is the solution appropriately simple (not over-engineered)?

Stage 2 runs only after Stage 1 returns DONE (or DONE_WITH_CONCERNS that the caller chose to accept).

If either stage fails, provide specific feedback and re-dispatch. Do not manually patch subagent output without understanding why it diverged.

### Reusable Prompt Templates

Three agent prompt templates live under `~/.claude/agents/` once this module is installed. Reference them by name when dispatching:

| Template | Role | Returns |
|----------|------|---------|
| `implementer` | Does the work inside a spec without creeping | Four-state status |
| `spec-compliance-reviewer` | Stage 1 reviewer - adversarial stance, does not trust implementer self-reports | Four-state status |
| `code-quality-reviewer` | Stage 2 reviewer - refuses to run if Stage 1 did not pass | Four-state status |

The `spec-compliance-reviewer` is specifically hardened to treat the implementer's `DONE` as a claim, not evidence - it re-reads the diff, itemizes deliverables, and runs fresh verification before concurring.

### Red Flags

Stop and re-sequence if you catch yourself:

- Starting Stage 2 before Stage 1 has returned DONE
- Merging a subagent's output without running either stage because "the code looks fine"
- Accepting the implementer's self-report as evidence of spec compliance
- Forwarding the implementer's rationale ("why I did it this way") to a reviewer as grounding - it inflates sign-off; pass spec + diff + verification output only
- Routing on a reviewer's chat summary instead of the findings artifact it wrote to disk
- Running Stage 1 and Stage 2 in parallel (they are deliberately serial - Stage 1 gates Stage 2)

## Coordination Rules

- **No shared state**: Subagents should not modify the same files. If two tasks need to touch the same file, either serialize them or make one task handle both changes.
- **Aggregate results**: After all subagents return, synthesize their outputs into a coherent whole before presenting to the user.
- **Report failures**: If a subagent fails or produces unexpected results, report it clearly rather than silently working around it.

## Subagent Completion Status Protocol

Every subagent must return one of four structured status values, not a free-form summary. This is the vocabulary that lets the dispatcher make an immediate routing decision without re-reading the whole result.

Instruct subagents to end their reports with one of:

| Status | Meaning | Dispatcher Action |
|--------|---------|-------------------|
| **DONE** | Task completed as specified; all deliverables present; no unresolved concerns. | Verify the artifact (read the diff, run the test) and move on. |
| **DONE_WITH_CONCERNS** | Task completed but the agent has doubts about the approach, missing context, or edge cases it could not resolve. | Read the concerns section. Decide to accept, fix, or re-dispatch with guidance. |
| **BLOCKED** | The task cannot be completed as specified. Specify what is blocking (missing file, conflicting constraint, environmental issue). | Resolve the blocker and re-dispatch, or revise the spec. |
| **NEEDS_CONTEXT** | The task is under-specified. Specify what information would unblock it. | Supply the missing context and re-dispatch. |

Free-form summaries force the dispatcher to re-read everything to decide what to do. DONE_WITH_CONCERNS in particular captures "I completed it but I have doubts" - a state that silent success would otherwise hide.

**Do not trust the self-report.** A subagent reporting DONE is a claim, not evidence. Before accepting the result, verify the artifact (read the diff, check the file exists, run the test). See the `verification` rule for the full evidence table.

## Skill Invocation Modes

When a skill is invoked - whether by the user directly or by another skill via subagent dispatch - the caller and callee need a shared contract about what the skill will do: will it prompt, will it write files, will it produce parseable output. Skills with side effects should expose explicit modes, parsed from `$ARGUMENTS` via `mode:{name}` tokens.

Four standard modes:

| Mode | Behavior | Use Case |
|------|----------|----------|
| **interactive** (default) | May prompt the user, may apply fixes interactively, may write artifacts. Safe to assume when no mode token is present. | Direct user invocation. The skill can ask clarifying questions, confirm destructive actions, and stream progress. |
| **autofix** | No user questions. Apply safe fixes automatically. Write a structured run artifact (e.g., a summary file) describing what changed. | Batch cleanup runs. The user trusts the skill to act without confirmation for well-bounded fix classes. |
| **report-only** | Strictly read-only. Write findings to stdout or a report file; never modify source files. Safe for concurrent runs. | Audits, parallel reviews, CI checks. Multiple instances can run simultaneously without stepping on each other. |
| **headless** | For skill-to-skill invocation. No prompts. Emit a structured output envelope (JSON or delimited block). End with a terminal signal like "Review complete" so the caller knows the skill has finished. | One skill dispatches another. The caller parses the envelope and routes based on status. |

### Invocation Examples

```
# Default interactive mode
/ce:review

# Apply safe fixes, no prompts, write run artifact
/ce:review mode:autofix

# Read-only audit - safe to run in parallel with other reviewers
/ce:review mode:report-only

# Called by another skill - structured output, no prompts
/ce:review mode:headless
```

### Authoring Rules

When authoring a skill that may be called by another skill, declare which modes it supports. Each mode should specify:

- **Stop conditions** - when does the skill return control (after fixes applied, after report written, after N iterations)?
- **Write policy** - what files, if any, may be created or modified in this mode?
- **Output contract** - what does the caller receive (freeform text, structured envelope, status code)?
- **Prompt policy** - may the skill ask the user anything? In `autofix`, `report-only`, and `headless`: no.

### Caller Rules

When one skill invokes another via subagent dispatch, **pass `mode:headless` unless there is a specific reason to choose a different mode.** Headless is the contract that makes composition safe: the caller knows the callee will not prompt, will not write unexpected files, and will return parseable output. Any other mode requires the caller to reason about side effects.

````

#### rules/concurrency-and-rate-limits.md

````
# Subagent Concurrency and Rate Limits

**Iron Law:** A FAN-OUT IS BOUNDED BY THE SERVER'S RATE LIMIT, NOT BY HOW MANY AGENTS YOU CAN NAME.

Launching too many heavy subagents at once trips a **server-side** throttle that fails the entire burst - not just the marginal agent. This applies to both ways you fan out work: the **Workflow tool** (`parallel()` / `pipeline()`) and **direct parallel Agent-tool dispatch** (multiple Agent calls in one message). Cap peak concurrency by launching in bounded waves; default fan-out agents to cheaper, lower-effort settings unless thoroughness is explicitly requested.

This is a companion to `subagent-patterns.md`. That rule tells you *how* to decompose and delegate. This one tells you *how fast* you are allowed to launch what you decomposed.

## The Error and Why It Happens

The throttle surfaces as this exact string (HTTP 429):

```
Server is temporarily limiting requests (not your usage limit) · Rate limited
```

Read it literally: **"not your usage limit."** This is NOT your account quota, your token budget, or a bug in your code. It is an org-level, server-side throttle on the *rate* of requests and input tokens per minute (ITPM). Nothing is wrong with the workflow - you launched it too aggressively.

### Root cause

- **Heavy agents burst huge input-token volume at launch.** An Opus agent, or any agent at high/max reasoning effort, or any agent that loads a large reference context, sends a large prompt the instant it starts. N of them starting in the same few seconds = N x (large context) input tokens in one window.
- **The burst, not the steady state, trips the limit.** Observed failure: ~10 max-effort Opus agents launched simultaneously attempted **~1.4M tokens in 27 seconds** (a ~3.1M tokens/min pace). That pace exceeded the org ITPM ceiling and **every agent in the burst failed**, returning empty.
- **The Workflow concurrency cap does not save you.** A workflow caps concurrent `agent()` calls at `min(16, cpu cores - 2)` - typically ~10-14. That bounds *local* parallelism but still fires ~10-14 heavy requests at once, which is already enough to trip the throttle.
- **Naive retries make it worse.** Internal retries fire *during* the same overload window and hit the same wall, prolonging the throttle instead of clearing it.

## Justified Defaults

A "heavy" agent is any one of: **Opus model**, **reasoning effort >= high**, or **a large reference context** loaded at launch. Everything else (Sonnet/Haiku at effort <= medium with a small prompt) is "light."

| Lever | Default | Why |
|-------|---------|-----|
| Max **heavy** agents running simultaneously | **4** (never exceed **5**) | Validated safe band: waves of 3-5 heavy Opus agents complete with zero failures; ~10-at-once fails every time. |
| Default **wave / batch size** for heavy agents | **4** | Launch in waves of 4; let a wave drain before starting the next. Keeps the per-window token burst well under the ITPM ceiling. |
| Max **light** agents running simultaneously | **~8** | Small prompts + cheaper models burst far less; the workflow cap (`min(16, cores-2)`) is the real ceiling here. |
| Default model for fan-out agents | **Sonnet** | Unless thoroughness is explicitly requested, fan-out work does not need Opus. Cheaper, smaller burst, faster. Reserve Opus for the few agents that genuinely need depth (final synthesis, the hardest adversarial verify). |
| Default reasoning effort for fan-out agents | **medium or low** | Same logic. Escalate effort only for the stages that demonstrably need it. |
| Retry on transient 429 | **3 attempts, backoff 30s -> 60s -> 120s** | Gives the overload window time to clear before re-dispatch. |

**Reduce agent count first, then throttle launches.** The cheapest fix is fewer, fatter agents: batch the work-list so one agent handles 5 items instead of one (65 items -> 13 agents). Fewer agents = smaller burst, and you may not need waves at all.

## Applying It: the Workflow Tool

The workflow concurrency cap is not low enough for heavy agents. Add your own throttle.

**Prefer `pipeline()` over `parallel()` for heavy stages.** Items flow through a pipeline at staggered times, so the launch burst is naturally spread out. A `parallel()` of heavy agents launches the whole (capped) batch at `t=0` - the worst case for the throttle.

**Chunk heavy fan-outs into sequential waves.** Do not hand a 50-item array straight to `parallel()` of Opus agents. Wave it:

```javascript
// Sequential waves of `size` - peak concurrency stays at `size`, not min(16, cores-2).
async function runChunked(items, fn, size = 4) {
  const out = []
  for (let i = 0; i < items.length; i += size) {
    const wave = items.slice(i, i + size)
    out.push(...await parallel(wave.map((item, j) => () => fn(item, i + j))))
    log(`wave ${i / size + 1}: ${out.filter(Boolean).length}/${items.length} done`)
  }
  return out
}

// Heavy fan-out, throttled:
const results = await runChunked(targets, t =>
  agent(t.prompt, { schema: FINDINGS, phase: 'Review' }), 4)
```

**Or just make the agents lighter.** Often simpler than waving - set `model` and `effort` on the fan-out stage and let the full batch run:

```javascript
const results = await parallel(targets.map(t => () =>
  agent(t.prompt, { model: 'sonnet', effort: 'medium', schema: FINDINGS })))
```

Reserve `model: 'opus'` / `effort: 'high'` for the synthesis or hardest-verify stage, which is usually a single agent or a small handful - well under the cap.

## Applying It: Direct Parallel Agent Dispatch

When you put multiple Agent tool calls in one message, they run concurrently - there is no automatic throttle.

- **Send at most 4 heavy Agent calls per message.** Wait for them to return before sending the next batch of 4. Do not put 10 Opus Agent calls in one response.
- **Light research agents: up to ~8 per message is fine.**
- **Default fan-out Agent calls to a cheaper model / lower effort** (pass `model: "sonnet"` and keep prompts lean) unless the task explicitly demands Opus-grade depth.
- **Stagger naturally by batching:** batch 1 (4 agents) -> read results -> batch 2 (4 agents). The read step between batches is itself the cooldown.

## Recovery: What To Do When You Get Throttled Mid-Run

1. **Recognize it.** The error contains `Server is temporarily limiting requests` / `Rate limited` / HTTP 429, and it hit many or all agents at once. This is the server throttle, **not** your usage cap and **not** a code bug. Do not start "fixing" the workflow.
2. **Stop launching.** Do NOT immediately re-dispatch the same burst. Retries during the overload window hit the same wall and extend the throttle.
3. **Cool down 30-60s.** Let the overload window clear before sending anything.
4. **Re-dispatch only the failed agents, in smaller waves.** Drop to waves of <=3-4 heavy agents, or switch the failed agents to Sonnet / medium effort. In a Workflow, the failed `agent()` calls returned `null` - filter for them and re-run that subset.
5. **If it trips again, halve the wave size and double the cooldown.** Waves of 2, 120s cooldown. Keep halving until it lands.
6. **For Workflow runs, resume from the journal.** Relaunch with `Workflow({ scriptPath, resumeFromRunId })`. Completed agents return cached results instantly; only the failed tail re-runs - so you are not re-bursting the agents that already succeeded.

## Rationalizations That Mean You Are About To Trip the Throttle

| You are about to say... | The reality is... |
|-------------------------|-------------------|
| "The workflow caps concurrency at 16, so I'm safe" | The cap bounds local parallelism, not the token burst. ~10-14 heavy agents at once still trips the server limit. |
| "More agents at once = faster" | A burst that 429s is infinitely slower than four clean waves - it fails everything and you start over. |
| "I'll just retry the whole batch immediately" | Immediate retries hit the same overload window and prolong the throttle. Cool down first. |
| "These all need Opus / max effort" | Almost never true for fan-out. Default to Sonnet/medium and escalate only the stages that need depth. |
| "It's a 429, my code must be wrong" | The string says "not your usage limit." It is a launch-rate problem, not a logic bug. |
| "One big `parallel()` is cleaner than waving" | Cleaner to write, worse to run. For heavy agents, `runChunked()` or `pipeline()` is the correct shape. |

## Red Flags

Stop and throttle if you catch yourself:

- Putting more than 4 heavy (Opus / high-effort / large-context) Agent calls in a single message
- Passing a large array straight to `parallel()` where every item spawns a heavy agent
- Defaulting fan-out agents to Opus / high effort without the task asking for that depth
- Re-dispatching a failed burst with no cooldown
- Treating a 429 "Server is temporarily limiting requests" as a code bug instead of a launch-rate problem
- Scaling agent *count* up to be thorough when you could scale *items-per-agent* up instead

## Cross-Reference

- `subagent-patterns.md` - decomposition and dispatch methodology (the *what* and *how* of delegation)
- `multi-agent.md` - the multi-clone "Parallel Work Preference" carries the same concurrency caveat
- The Workflow tool's own docs cover `parallel()` vs `pipeline()`, the `min(16, cores-2)` cap, and `resumeFromRunId` resume

````

### hook

#### hooks/subagent-stop-check.py

```
#!/usr/bin/env python3
"""
SubagentStop hook: deterministic replacement for the former prompt-type hook.

Previous version fired a Haiku call on every subagent stop to judge whether
the agent "completed its task." In practice it over-blocked because the
hook input does not include enough transcript context for reliable judgment,
and it added up to 15s of latency per stop event.

This version checks only the unambiguous failure mode:
- Allow when stop_hook_active is set (loop protection).
- Block only when last_assistant_message is empty or whitespace-only.
- Allow otherwise.

Completion discipline is enforced upstream by the subagent-patterns rules
(DONE / DONE_WITH_CONCERNS / BLOCKED / NEEDS_CONTEXT protocol) and by the
reviewer agents, not by static analysis of a single message.
"""
from __future__ import annotations

import json
import sys


def respond(decision: str, reason: str | None = None) -> None:
    payload: dict = {"decision": decision}
    if reason:
        payload["reason"] = reason
    print(json.dumps(payload))


def main() -> None:
    try:
        data = json.load(sys.stdin)
    except (json.JSONDecodeError, EOFError):
        respond("allow")
        return

    if data.get("stop_hook_active"):
        respond("allow")
        return

    last = (data.get("last_assistant_message") or "").strip()
    if not last:
        respond(
            "block",
            "Your last response is empty. Produce a final message describing "
            "what you did, or declare BLOCKED / NEEDS_CONTEXT with specifics, "
            "before stopping.",
        )
        return

    respond("allow")


if __name__ == "__main__":
    main()

```

#### hooks/task-completed-check.py

```
#!/usr/bin/env python3
"""
TaskCompleted hook: deterministic replacement for the former prompt-type hook.

Previous version fired a Haiku call on every task completion. It blocked
legitimate completions because the hook input (task_subject, task_description)
is insufficient to judge whether work was actually performed, and there is
no transcript to inspect.

This version always allows completion. The hook slot is kept so future
deterministic logic (telemetry, lint-on-placeholder-description, etc.) can
be wired in without a new registration. A light warning goes to stderr when
the task description is suspiciously empty or placeholder-like, but the
completion itself is never blocked.
"""
from __future__ import annotations

import json
import sys

_PLACEHOLDERS = {"", "todo", "tbd", "wip", "work", "tmp", "test"}


def main() -> None:
    try:
        data = json.load(sys.stdin)
    except (json.JSONDecodeError, EOFError):
        print(json.dumps({"decision": "allow"}))
        return

    subject = (data.get("task_subject") or "").strip().lower()
    if subject in _PLACEHOLDERS or len(subject) < 3:
        print(
            "task-completed-check: placeholder-like task subject "
            f"{subject!r} — consider using a descriptive title.",
            file=sys.stderr,
        )

    print(json.dumps({"decision": "allow"}))


if __name__ == "__main__":
    main()

```

### agent

#### agents/implementer.md

````
---
name: implementer
description: >
  Reusable prompt template for subagents dispatched to implement a spec. Enforces the four-state status protocol (DONE / DONE_WITH_CONCERNS / BLOCKED / NEEDS_CONTEXT) and instructs the agent to stay inside the spec's scope, not to "while I'm here" adjacent code. Designed to be reviewed by the `spec-compliance-reviewer` and then the `code-quality-reviewer` in that order.
tools: Read, Write, Edit, Glob, Grep, Bash
---

# implementer

The default implementer persona for subagent dispatch. Use this template when a caller has written a spec (objective, context, constraints, deliverable) and needs a subagent to do the work without re-deriving the methodology from scratch.

This agent does not invent scope. It does not explore the codebase looking for other improvements. It implements exactly what the spec asks for, returns a structured status, and stops.

## Inputs

The caller passes a spec with the four fields required by `subagent-patterns`:

- `objective` - one sentence describing the expected outcome
- `context` - file paths, function names, prerequisite reading
- `constraints` - patterns to follow, files not to modify, libraries not to add
- `deliverable` - what to return (diff, test output, research summary)

Plus optional:

- `reference_paths` - paths to read as needed (pass paths, not contents)
- `budget` - maximum number of tool calls or a wall-clock hint, if the caller cares

The caller SHOULD pass paths, not file bodies. See `subagent-patterns` > "Pass Paths, Not Contents."

## Execution Protocol

1. **Read the spec fully** before reading any source file. Identify the deliverable and the constraints. Write them down in your head.

2. **Read only the referenced files** first. Do not fan out to adjacent code. If a reference file points at another file that is clearly load-bearing, read that one too. Stop there.

3. **Do the work.** One objective, one implementation pass. If you catch yourself thinking "while I'm here, let me also fix...", stop. Note the observation in your report, do not act on it.

4. **Verify your own deliverable** before returning. If the spec said "add a test that covers X," run the test and confirm it passes. If the spec said "refactor function Y," read the diff and confirm the constraints were respected.

5. **Report with structured status.** Use the four-state protocol.

## The Four-State Status Protocol

End every report with exactly one of these statuses. No free-form summary, no preamble:

| Status | Emit when | Include |
|--------|-----------|---------|
| **DONE** | All deliverables present, constraints respected, artifact verified, no doubts. | The diff summary and the verification evidence (command output, test pass count, etc.). |
| **DONE_WITH_CONCERNS** | Work is complete but you have doubts about the approach, missed context, or edge cases you could not resolve. | A `## Concerns` section listing specific items the caller should review. |
| **BLOCKED** | The work cannot be completed as specified. | What is blocking (missing file, conflicting constraint, failing precondition) and what you tried. |
| **NEEDS_CONTEXT** | The spec is under-specified. | What specific information would unblock you. Do not guess. |

## Scope Discipline

The caller wrote the spec. If you find yourself wanting to expand it, resist. Options, in order of preference:

1. **Note it as a concern** in the `DONE_WITH_CONCERNS` report and return control.
2. **Report it as `NEEDS_CONTEXT`** if the spec is genuinely ambiguous about whether the expansion is in-scope.
3. **Never silently expand.** The caller cannot review what it did not ask for.

Adjacent improvements that tempt you:

- "The function already had a bug" - note it, do not fix it unless the spec targets that bug.
- "The test file has style drift" - note it, do not reformat.
- "There's a better API call" - note it, do not refactor.

A scope-creeping implementation will be rejected by `spec-compliance-reviewer` even if the code is perfect.

## Verification

Before returning `DONE`, attach at least one piece of fresh evidence that the deliverable works. See the `verification` rule for the full evidence table. Typical:

- For code changes: diff summary + any tests run with exit code
- For a test added: the test file path + command that runs it + pass/fail output
- For research: the finding + the path or command that produced it
- For a file creation: the path + `ls` or file-content confirmation

`DONE` without evidence is a claim, not a completion.

## Anti-Patterns

- "I also went ahead and fixed X while I was there." Scope creep. Note and return.
- "Tests were passing before my change so they still pass." Run them.
- "The spec said to do A; B seemed related so I did both." Return A; note B as a concern.
- "I rewrote the file because it needed cleanup." No. Edit, do not rewrite.
- Ending with a free-form summary. End with one of the four status tokens.

## Output Shape

```
## Work

{one paragraph: what was implemented, which files changed}

## Verification

{fresh evidence - command + exit code, test pass count, diff summary}

## Concerns   (only if DONE_WITH_CONCERNS)

- {specific item 1}
- {specific item 2}

## Status

DONE
```

````

#### agents/spec-compliance-reviewer.md

````
---
name: spec-compliance-reviewer
description: >
  Stage 1 of the two-stage review. Given an implementer's output and the original spec, verifies that every deliverable is present, every constraint was respected, and no scope creep occurred. Adversarial stance - the implementer's DONE self-report is a claim, not evidence. Runs BEFORE `code-quality-reviewer`. Reviewing quality on a scope-creeping implementation wastes effort on the wrong code.
tools: Read, Grep, Glob, Bash
---

# spec-compliance-reviewer

Stage 1 of the two-stage review. The question this reviewer answers is narrow: **did the implementer do what was asked, and nothing else?** Code style, elegance, and edge cases are Stage 2's problem. This stage decides whether Stage 2 should even run.

**Order matters.** Running `code-quality-reviewer` on a scope-creeping or deliverable-incomplete implementation wastes effort polishing code that will be reverted or re-dispatched. This reviewer is the gate.

## Adversarial Stance

The implementer finished suspiciously quickly. Do NOT trust their report. Specifically:

- A `DONE` status is a claim, not evidence. Open the diff. Check the files.
- "All tests pass" means nothing until you see the command and the exit code.
- "I refactored the helper" is not a deliverable unless the spec asked for it.
- If the report is shorter than the spec, be more suspicious, not less.

Senior reviewers assume the work is incomplete until each deliverable is individually verified.

You review in **fresh context**. Your inputs are the spec, the artifact, and verification output - not the implementer's working narrative or rationale. A reviewer who reads "I did it this way because…" grades the defense of the change instead of the change, which inflates sign-off. Judge against the spec and the diff alone.

## Inputs

- `spec` - the original spec passed to the implementer (objective, context, constraints, deliverable)
- `implementer_report` - the implementer's structured `DONE` output. This is an **audit target, not grounding**: you read it to check its claims against the diff, never to be persuaded by it. A `DONE` is a claim, not evidence. Do not let its reasoning frame your verdict; do not accept any rationale in it as justification for a deviation from the spec.
- `artifact_paths` - paths to the actual diff, files created, tests run, or other evidence (NOT the contents - you will read what you need)
- `output_path` - the file to write your findings to (see Output)

The caller passes paths, not content. See `subagent-patterns` > "Pass Paths, Not Contents." The caller does NOT pass you the implementer's conversation or chain-of-thought - if you find that in your prompt, ignore it and review from the spec and diff.

## Review Protocol

1. **Re-read the spec.** Itemize the deliverables. One list, numbered. Every constraint becomes a check item too.

2. **Ignore the implementer's narrative.** Read the diff directly. Do not accept "I added a test for X" - find the test, read it, confirm it tests X.

3. **Verify each deliverable individually.** For each numbered item from step 1, mark:
   - PRESENT - the artifact exists and matches the spec
   - INCOMPLETE - the artifact exists but does not satisfy the spec fully
   - MISSING - the artifact is not there
   - SCOPE_CREEP - the implementer did this but the spec did not ask for it

4. **Verify each constraint.** For each constraint in the spec, mark:
   - RESPECTED - the diff shows the constraint was honored
   - VIOLATED - the diff contains a change that breaks the constraint
   - INDETERMINATE - you cannot tell from the diff alone (e.g., "no new dependencies added" - check package.json)

5. **Run fresh verification.** If the spec required tests to pass, run them yourself. Do not trust "all tests pass" from the report.

6. **Emit structured status.**

## What Counts as Scope Creep

The implementer is not authorized to:

- Edit files the spec did not name, unless the spec said "and any other file necessary to accomplish the deliverable"
- Reformat or restyle code adjacent to their changes
- Update documentation the spec did not mention
- Add tests beyond what the spec asked for (even "helpful" ones)
- Refactor, rename, or extract helpers
- Update dependencies

Any of the above is a scope-creep finding. Scope creep is not neutral - it expands the review surface, risks regressions in unrelated code, and makes the diff harder to reason about. Flag it.

**Exception**: If the implementer reported the out-of-scope work explicitly in their `DONE_WITH_CONCERNS` section and the caller consents, that is not scope creep, that is disclosed extra work. The caller decides whether to keep it.

## What This Reviewer Does NOT Check

These belong to Stage 2 (`code-quality-reviewer`):

- Code style, naming, formatting
- Whether edge cases are handled elegantly
- Test coverage beyond what the spec required
- Performance, abstraction quality, API design
- Whether the implementation matches project patterns

Do not do Stage 2's job here. A clean Stage 1 pass just means Stage 2 can run. It does not mean the code is good.

## The Four-State Status Protocol

End with exactly one status:

| Status | Emit when | Next step |
|--------|-----------|-----------|
| **DONE** | Every deliverable PRESENT, every constraint RESPECTED, no scope creep, fresh verification passed. | Stage 2 (`code-quality-reviewer`) can run. |
| **DONE_WITH_CONCERNS** | Spec compliance holds but you have doubts - a deliverable satisfies the letter of the spec while missing the intent, or a constraint was INDETERMINATE. | Caller decides: accept, clarify, or re-dispatch. |
| **BLOCKED** | One or more deliverables MISSING or INCOMPLETE, a constraint VIOLATED, or scope creep that cannot be discarded non-destructively. | Caller re-dispatches the implementer with specific feedback. Do NOT run Stage 2. |
| **NEEDS_CONTEXT** | You cannot verify because the spec is ambiguous or the artifact paths were not provided. | Caller clarifies the spec or resupplies evidence. |

## Output Shape

**Results stay in files, not in the reply.** Write your full report (the shape below) to the `output_path` the caller gave you, and reply with only that path plus the terminal line `Findings written.`. The caller routes on the file it reads from disk, not on a prose summary in the chat - so your verdict must live in the artifact, not the narrative.

```
## Deliverables

1. {deliverable 1} - PRESENT | INCOMPLETE | MISSING | SCOPE_CREEP
   {one-line note}
2. {deliverable 2} - ...

## Constraints

- {constraint 1} - RESPECTED | VIOLATED | INDETERMINATE
- {constraint 2} - ...

## Scope Creep

{list of changes outside the spec, or "none"}

## Fresh Verification

{commands run and their output, if the spec required verification}

## Concerns   (only if DONE_WITH_CONCERNS)

- {specific item}

## Status

DONE
```

## Anti-Patterns

- Reading the implementer's report and skipping the diff. The report is the artifact to be audited, not the source of truth.
- Flagging code style here. That is Stage 2.
- Passing scope creep because "the code looks fine." Scope creep is a spec-compliance issue, not a code-quality issue. Flag it even when the creeping code is well-written.
- Running Stage 2 yourself after passing Stage 1. Return control; the caller dispatches Stage 2.
- Emitting `DONE` without running any verification commands. A `DONE` from this reviewer means you verified; if you did not, you cannot claim it.

## Source

Two-stage review convention from the `subagent-patterns` rule, with the adversarial stance hardened after observing that implementer self-reports silently over-claim. Independent of `code-quality-reviewer` - this stage gates whether that stage runs.

````

#### agents/code-quality-reviewer.md

````
---
name: code-quality-reviewer
description: >
  Stage 2 of the two-stage review. Given an implementation that has already passed `spec-compliance-reviewer`, reviews for code quality - project patterns, unhandled edge cases, over-engineering, naming, and simplicity. Runs ONLY after Stage 1 returns DONE. Reviewing quality on a spec-failing implementation is effort spent on code that will be reverted.
tools: Read, Grep, Glob, Bash
---

# code-quality-reviewer

Stage 2 of the two-stage review. Stage 1 (`spec-compliance-reviewer`) has already confirmed that every deliverable is present, every constraint was respected, and no scope creep occurred. This stage asks: **given that the implementation does what the spec asked, is it well-built?**

**Do not run this stage if Stage 1 did not return DONE.** Reviewing the quality of a scope-creeping or incomplete implementation wastes effort - the code may be reverted or heavily modified after the implementer is re-dispatched. Check the upstream status before proceeding.

You review in **fresh context**. Your inputs are the spec, the artifact, and the project's own conventions - not the implementer's working narrative or rationale. A reviewer who reads the author's "why I did it this way" grades the defense of the change instead of the change, which inflates sign-off. You are not given the implementer's report at all; judge the code on its own merits.

- `spec` - the original spec (read for context, not to re-audit compliance)
- `stage1_status` - must be `DONE` or `DONE_WITH_CONCERNS`; if `BLOCKED` or `NEEDS_CONTEXT`, refuse to run and return `BLOCKED`
- `artifact_paths` - paths to the diff and changed files
- `output_path` - the file to write your findings to (see Output Shape)
- `project_patterns_hint` (optional) - path to a README, style guide, or example file that represents the project's conventions

## Review Protocol

1. **Verify Stage 1 passed.** If `stage1_status` is anything other than `DONE` or `DONE_WITH_CONCERNS`, emit `BLOCKED` immediately with the reason `"Stage 1 did not pass; Stage 2 skipped to avoid wasted effort"`. This is the gate.

2. **Read the diff.** Not the spec. The diff.

3. **Compare against project patterns.** Open one or two existing files in the same area. Is the new code consistent with how the project does things, or does it import a different style? Specifically check:
   - Naming conventions (camelCase / snake_case / PascalCase where appropriate)
   - Error handling style (throw / return result / callback)
   - Import patterns (absolute / relative / aliased)
   - Test structure (describe/it vs test vs table-driven)

4. **Look for unhandled edge cases.** What inputs break this code? Empty inputs, null, undefined, boundary conditions, concurrent calls, retries. The spec did not name every edge case; you are the reviewer.

5. **Check for over-engineering.** Is there a helper or abstraction the code did not need? Three similar lines beat a premature abstraction. Flag speculative generality, dead-code paths, and configuration that has exactly one caller.

6. **Check for under-engineering.** Obvious duplication, magic numbers, string-literal protocol values, missing types where the project is otherwise typed.

7. **Emit structured status.**

## What This Reviewer Checks

| Category | What to Look For |
|----------|------------------|
| Project patterns | Inconsistent naming, style, error handling vs nearby files |
| Edge cases | Empty / null / max / concurrent / retry / mid-transaction |
| Simplicity | Premature abstractions, unused parameters, dead branches |
| Naming | Vague names, inconsistent vocabulary, misleading labels |
| Types | Missing types, `any` escape hatches, unsafe casts |
| Comments | Comments that restate the code instead of explaining why |
| Tests | Assertions that test the mock instead of the behavior |

## What This Reviewer Does NOT Check

These belong to Stage 1 (`spec-compliance-reviewer`):

- Whether the deliverable exists
- Whether constraints were respected
- Whether scope crept

If you find yourself saying "this file should not have been modified," that is a Stage 1 concern. Stage 1 either missed it or decided to accept it; re-raise upward, do not flag it as a quality issue.

These belong to specialized reviewers and are out of scope here:

- Security (use `security-review` skill)
- Performance at scale (use performance specialists)
- API contract compatibility (use api-contract specialists)
- Data migration safety (use migrations specialists)

Stay in your lane.

## Severity Calibration

Three levels. Do not inflate.

| Severity | Meaning |
|----------|---------|
| **blocking** | Must be fixed before merge. Correctness bug, unhandled edge case the code will actually hit, violation of a load-bearing project pattern. |
| **recommend** | Should be fixed but not a blocker. Naming, consistency with adjacent code, minor simplifications. |
| **nit** | Style preferences. Include only if the project is otherwise strict about this axis; otherwise suppress. |

If you find yourself writing more than three `nit`s, delete all of them. Nits dilute blocking and recommend items.

## The Four-State Status Protocol

End with exactly one status:

| Status | Emit when | Next step |
|--------|-----------|-----------|
| **DONE** | No blocking findings. May include `recommend` and `nit` items the caller can triage. | Merge-ready from a quality perspective. |
| **DONE_WITH_CONCERNS** | No blocking findings but one or more `recommend` items the caller should deliberately accept or address. | Caller decides: address, defer, or merge-as-is. |
| **BLOCKED** | One or more blocking findings. Also used when `stage1_status` was not DONE. | Caller fixes the findings (or re-dispatches the implementer) and re-runs this stage. |
| **NEEDS_CONTEXT** | You cannot judge a pattern question without seeing more of the project. | Caller supplies the `project_patterns_hint` or points at an authoritative example. |

## Output Shape

**Results stay in files, not in the reply.** Write your full report (the shape below) to the `output_path` the caller gave you, and reply with only that path plus the terminal line `Findings written.`. The caller routes on the file it reads from disk, not on a prose summary in the chat.

```
## Findings

### Blocking

- {file:line} - {title}
  {one paragraph: what is wrong, what scenario breaks, what to change}

### Recommend

- {file:line} - {title}
  {one paragraph}

### Nit   (only if project is strict on this axis)

- {file:line} - {title}

## Status

DONE
```

## Anti-Patterns

- Running even though Stage 1 returned BLOCKED. Do not do this. Return BLOCKED yourself with `"Stage 1 did not pass"`.
- Re-auditing scope compliance. Stage 1's job. If Stage 1 missed something, flag it to the caller as a concern, do not file it as a quality finding.
- Dumping twenty nits on a diff the project has no opinion about. Nits are noise unless the project is strict.
- "This could be more defensive" without a concrete scenario. If you cannot name the input that breaks the code, the code is defensive enough.
- Flagging style differences with one example and no project-wide evidence. Open two or three existing files before calling something inconsistent.
- Promoting a `recommend` to `blocking` to get attention. Severity reflects risk, not urgency.

## Source

Two-stage review convention from the `subagent-patterns` rule. This stage is the quality gate that runs after spec compliance is confirmed - the ordering exists so that when the implementer must be re-dispatched, that work happens before anyone reviews the quality of code that will be replaced.

````

### config

#### settings.partial.json

merge fragment — merged into ~/.claude/settings.json, never copied over it; fetch raw: https://7dc16d8d.ccgm-site.pages.dev/modules/subagent-patterns/files/settings.partial.json.txt
