self-subagent

name

self-subagent

description

Orchestrate parallel sub-tasks by spawning non-interactive instances of your own CLI as subagents. Use when you need to parallelize work across multiple files, run independent investigations simultaneously, or delegate heavy multi-step tasks. Works with ANY AI coding CLI agent (Amp, Claude Code, Codex, Cursor, OpenCode, aider, Cline, Roo, goose, Windsurf, Copilot CLI, pi, etc.). Triggers on "run in parallel", "subagent", "delegate", "fan out", "concurrent tasks", or any complex task that benefits from parallel execution.

Self-Subagent Orchestration

Spawn parallel copies of yourself in non-interactive mode to do work concurrently.

YOU (parent, interactive)
 ├─ spawn ──→ [self --exec "task A"]  ──→ result A ─┐
 ├─ spawn ──→ [self --exec "task B"]  ──→ result B ─┼─→ collect → verify → done
 └─ spawn ──→ [self --exec "task C"]  ──→ result C ─┘

Each subagent is fire-and-forget: receives a complete prompt, does the work, exits. No follow-ups.

Phase 1: Discover Your Execute Mode

You must figure out how to invoke yourself non-interactively. Do not assume — discover.

1a. Identify what CLI you are

# Check parent process
ps -p $PPID -o comm= 2>/dev/null

# Check known agent CLIs on PATH
for cmd in amp claude codex cursor opencode aider pi goose cline roo windsurf copilot; do
  command -v "$cmd" &>/dev/null && echo "$cmd"
done

1b. Read your own --help

Once identified, read the help to find the non-interactive/execute/print mode:

# Replace YOUR_CLI with the identified binary
YOUR_CLI --help 2>&1 | grep -iE 'exec|non.?interactive|print|batch|run|pipe|headless|-p |-x '
YOUR_CLI exec --help 2>&1   # some CLIs nest it under a subcommand
YOUR_CLI run --help 2>&1

Look for flags that indicate:

• Non-interactive execution: exec, run, -x, -p, --print, --batch, --headless
• Auto-approve / skip permissions: --yes, --auto, --full-auto, --dangerously-*, --no-confirm
• Structured output: --json, --output-format, --stream-json
• Stdin support: --stdin, - as argument, pipe support

1c. If unknown, use web search or tool docs

If --help is insufficient, search for documentation:

• Search: "<cli-name> non-interactive mode" or "<cli-name> exec mode"
• Check the CLI's GitHub README
• Look for AGENTS.md, CLAUDE.md, or similar instruction files in the project root

1d. Known profiles (quick reference)

CLI	Execute command	Auto-approve	JSON output
amp	amp -x "prompt"	--dangerously-allow-all	--stream-json
claude	claude -p "prompt"	--dangerously-skip-permissions	--output-format json
codex	codex exec "prompt"	--full-auto	--json
aider	echo "prompt" | aider --yes-always	built-in	—
opencode	opencode run "prompt"	—	—
pi	pi -p "prompt"	—	—
goose	goose session --non-interactive "prompt"	—	—

Full details, edge cases, and output capture: see references/cli-profiles.md

1e. Test it

Before spawning real work, validate with a trivial prompt:

AGENT_CMD="claude -p --dangerously-skip-permissions"  # or whatever you discovered
echo "Reply with exactly: PING" | timeout 30 $AGENT_CMD 2>&1
# Should output something containing "PING"

1f. Fallback

If no non-interactive mode exists, fall back to shell scripts with standard tools:

bash -c 'cat src/auth.ts | head -50 && echo "ANALYSIS: ..."'

This loses AI reasoning but still enables parallel scripted work.

Phase 2: Decompose Into a Task Graph

Do NOT just list tasks. Build a dependency graph — this is what enables maximum parallelism.

2a. Identify tasks and their write targets

For each task, declare:

• id: short identifier
• writes: files this task will create or modify
• reads: files this task needs (read-only)
• depends_on: task IDs that must complete first

2b. Build the graph

Example: "Add logging and tests to auth + payments modules"

  task1: {id: "log-auth",     writes: [src/auth.ts],              depends_on: []}
  task2: {id: "log-payments",  writes: [src/payments.ts],          depends_on: []}
  task3: {id: "test-auth",     writes: [tests/auth.test.ts],       depends_on: ["log-auth"]}
  task4: {id: "test-payments", writes: [tests/payments.test.ts],   depends_on: ["log-payments"]}
  task5: {id: "update-ci",     writes: [.github/workflows/ci.yml], depends_on: ["test-auth", "test-payments"]}

  Wave 1: [task1, task2]           ← parallel (disjoint writes, no deps)
  Wave 2: [task3, task4]           ← parallel (disjoint writes, wave 1 done)
  Wave 3: [task5]                  ← serial (depends on wave 2)

2c. Scheduling rules

Condition	Action
No dependency + disjoint writes	Parallel
Depends on another task's output	Wait for dependency
Two tasks write the same file	Serialize OR use git worktrees
Read-only task (research, review)	Always parallelizable
> 6 tasks ready simultaneously	Throttle to 6 concurrent

2d. Wave execution

Group tasks into waves — each wave is a set of tasks that can all run in parallel:

Wave 1: all tasks with 0 unmet dependencies    → spawn all, wait all
Wave 2: tasks whose deps were all in wave 1     → spawn all, wait all
...repeat until all tasks complete

Phase 3: Write Subagent Prompts

Each prompt must be completely self-contained. The subagent knows nothing about your session.

Template

ROLE: You are a focused code executor. Do exactly what is asked. Do not explore beyond scope.
GOAL: [one sentence]
WORKING DIRECTORY: [absolute path]
READ FIRST: [file list — the subagent should read these to understand context]
MODIFY: [exact file list — the ONLY files the subagent may write to]
DO NOT MODIFY: anything not listed above
CONSTRAINTS:
- [coding style, framework, patterns to follow]
- [specific things to avoid]
DELIVERABLES:
- [what each output file should contain]
VALIDATION:
- [command to run, e.g. "npx tsc --noEmit && npm test -- --testPathPattern=auth"]
CONTEXT:
[paste relevant code snippets, types, interfaces — anything the subagent needs]

Prompt size guidelines

• Include all necessary context inline — file contents, type definitions, examples
• For large contexts (>4K chars), write to a temp file and instruct the subagent to read it
• Be extremely specific about constraints — the subagent will improvise if you're vague

Role prefixes

Role	Prefix	Use for
Executor	"You are a focused code executor."	Implementation, refactors, migrations
Researcher	"You are a codebase researcher. Do NOT edit any files."	Code search, architecture analysis
Reviewer	"You are a senior code reviewer. Do NOT edit any files."	Code review, security audit
Planner	"You are a technical planner. Do NOT edit any files."	Architecture decisions, migration plans

Context Sharing (Token Optimization)

When spawning multiple subagents that need the same context (types, guidelines, configs), do not inline the text in every prompt. This wastes tokens.

1. Pack context once:

   ./skill/context-packer.sh "$TMPDIR/shared-context.md" src/types.ts docs/guidelines.md
   

2. Reference it:

   PROMPT="...
   Read $TMPDIR/shared-context.md for types and guidelines.
   ..."
   

Math:

• Inline 200 lines of types (2KB) × 5 subagents = 10KB overhead.
• Shared file (2KB) read once by 5 subagents = 2KB storage + ~50 tokens instruction overhead.
• Savings: ~90% on context tokens.

Phase 4: Spawn, Collect, Verify

4a. Spawn a wave

AGENT_CMD="claude -p --dangerously-skip-permissions"  # from Phase 1
TMPDIR=$(mktemp -d)
PIDS=()
TASK_NAMES=()

spawn_task() {
  local id="$1" prompt="$2"
  timeout 300 $AGENT_CMD "$prompt" > "$TMPDIR/$id.out" 2>&1 &
  PIDS+=($!)
  TASK_NAMES+=("$id")
}

# Wave 1
spawn_task "log-auth" "$(cat <<'EOF'
ROLE: You are a focused code executor.
GOAL: Add structured logging to src/auth.ts
...
EOF
)"

spawn_task "log-payments" "$(cat <<'EOF'
ROLE: You are a focused code executor.
GOAL: Add structured logging to src/payments.ts
...
EOF
)"

# Wait for wave
FAILED=()
for i in "${!PIDS[@]}"; do
  if ! wait "${PIDS[$i]}"; then
    FAILED+=("${TASK_NAMES[$i]}")
  fi
done

4b. Collect results

for id in "${TASK_NAMES[@]}"; do
  echo "=== $id (exit: $(wait ${PIDS[$i]}; echo $?)) ==="
  tail -20 "$TMPDIR/$id.out"  # last 20 lines usually have the summary
done

# See what actually changed on disk
git diff --stat

4c. Retry failures (Session Resumption)

If a task fails, resume the existing session instead of restarting. This saves tokens (no need to re-read context) and preserves the subagent's mental state.

1. Check CLI capabilities: Does your CLI support --resume or persistent sessions?

   • Claude: claude -p --resume <session_id>
   • Codex: codex exec resume <session_id>

2. Implementation:

for id in "${FAILED[@]}"; do
  # Retrieve session ID from previous run's log or output (CLI-specific)
  SESSION_ID=$(grep "Session ID:" "$TMPDIR/$id.out" | awk '{print $NF}')
  ERROR=$(tail -50 "$TMPDIR/$id.out")
  
  FIX_PROMPT="PREVIOUS ATTEMPT FAILED. Error output:
$ERROR

Fix the issue. Do not repeat the same mistake."

  if [[ -n "$SESSION_ID" && "$AGENT_CMD" == *"claude"* ]]; then
    # Resume session (cheaper, faster)
    timeout 300 $AGENT_CMD --resume "$SESSION_ID" "$FIX_PROMPT" > "$TMPDIR/$id.retry.out" 2>&1
  else
    # Fallback: Restart with context injection
    FULL_PROMPT="$ORIGINAL_PROMPT

$FIX_PROMPT"
    timeout 300 $AGENT_CMD "$FULL_PROMPT" > "$TMPDIR/$id.retry.out" 2>&1
  fi
done

After 1 retry, do the task yourself — don't loop.

4d. Verify the wave

Run project-wide validation after each wave:

# Adapt to your project
npx tsc --noEmit && npm test && npm run lint

Only proceed to the next wave if validation passes.

4e. Diff-Based Verification (Pre-Merge)

Before running the quality gate, verify the diff itself is safe to merge.

The diff-verify.sh script performs three checks on the raw git diff:

Check	What	Action on Failure
Secret Scan	Scans added lines for API keys, tokens, credentials	Hard block (exit 2) + auto-revert
Rogue Edit Detection	Flags files modified outside declared targets	Reject (exit 1) + auto-revert
Diff Proportionality	Checks total changes vs task complexity threshold	Reject (exit 1) + auto-revert

Secret Detection Patterns

Scans for 25+ patterns across:

• Generic: api_key, secret, password, token, private_key
• Provider-specific: OpenAI (sk-), GitHub (ghp_, gho_, ghs_), AWS (AKIA), Stripe (sk_live_), Slack (xox), Google (AIza), SendGrid (SG.)
• Structural: PEM private keys, connection strings with embedded credentials
• Suspicious markers: TODO.*remove.*key, FIXME.*secret

Allowlist exempts: process.env, os.environ, shell variable refs, placeholder, test_key, mock_secret

Usage

# Standalone
./skill/diff-verify.sh <subagent_dir> <results_dir> <expected_files> [complexity]

# Exit codes: 0=PASS, 1=FAIL, 2=SECRETS_FOUND

# Integrated (called automatically by quality-gate.sh Phase 0)
./skill/quality-gate.sh <subagent_dir> <results_dir> <expected_files> [complexity]
# Now runs diff verification FIRST, then quality scoring

Auto-Revert

On any verification failure, changes are automatically reverted:

git checkout -- .   # revert tracked changes
git clean -fd       # remove untracked files

This ensures the working directory is clean before:

• Retrying the subagent with error context
• Proceeding to the next wave
• Falling back to inline execution

Exit Code Chain

quality-gate.sh exit	Meaning	What Happened
0	ACCEPT	Diff clean + score >= 6
1	REJECT	Diff failed OR score < 6
2	SECRETS_FOUND	Hard block, auto-reverted

4f. Quality Gate

Before accepting any subagent's output, score it 0-10 on three criteria:

Gate Criteria

Criterion	Weight	Check
File Scope	4 pts	Only modified declared files, no rogue edits
Validation	4 pts	Typecheck/lint/tests pass
Diff Size	2 pts	Diff proportional to task complexity

Scoring Algorithm

#!/usr/bin/env bash
# quality-gate.sh - Score subagent output before merging

SUBAGENT_DIR="$1"      # Temp worktree or directory
RESULTS_DIR="$2"       # Where to save scores
EXPECTED_FILES="$3"    # Space-separated list of expected modified files
TASK_COMPLEXITY="${4:-medium}"  # small|medium|large

cd "$SUBAGENT_DIR"

SCORE=10
FAILURES=""

# 1. File Scope Check (4 points)
MODIFIED=$(git diff --name-only 2>/dev/null | sort)
UNEXPECTED=0
MISSING=0

for file in $MODIFIED; do
  if [[ ! " $EXPECTED_FILES " =~ " $file " ]]; then
    UNEXPECTED=$((UNEXPECTED + 1))
    FAILURES="${FAILURES}UNEXPECTED: $file\n"
  fi
done

for expected in $EXPECTED_FILES; do
  if ! echo "$MODIFIED" | grep -q "^$expected$"; then
    MISSING=$((MISSING + 1))
    FAILURES="${FAILURES}MISSING: $expected\n"
  fi
done

if [[ $UNEXPECTED -gt 0 || $MISSING -gt 0 ]]; then
  SCORE=$((SCORE - 4))
  echo "⚠️  File scope violation: $UNEXPECTED unexpected, $MISSING missing"
fi

# 2. Validation Check (4 points)
VALIDATION_FAILED=0

# TypeScript
if command -v npx >/dev/null 2>&1; then
  if ! npx tsc --noEmit 2>&1 | head -20; then
    SCORE=$((SCORE - 2))
    VALIDATION_FAILED=1
    FAILURES="${FAILURES}TypeScript compilation failed\n"
    echo "❌ TypeScript compilation failed"
  fi
fi

# Lint
if [[ -f "package.json" ]] && grep -q '"lint"' package.json 2>/dev/null; then
  if ! npm run lint 2>&1 | tail -10; then
    SCORE=$((SCORE - 1))
    VALIDATION_FAILED=1
    FAILURES="${FAILURES}Lint failed\n"
    echo "❌ Lint failed"
  fi
fi

# Tests
if [[ -f "package.json" ]] && grep -q '"test"' package.json 2>/dev/null; then
  if ! npm test 2>&1 | tail -10; then
    SCORE=$((SCORE - 1))
    VALIDATION_FAILED=1
    FAILURES="${FAILURES}Tests failed\n"
    echo "❌ Tests failed"
  fi
fi

# 3. Diff Size Check (2 points)
DIFF_LINES=$(git diff --stat 2>/dev/null | tail -1 | awk '{print $1}')

# Thresholds by complexity
if [[ "$TASK_COMPLEXITY" == "small" ]]; then
  MAX_LINES=50
elif [[ "$TASK_COMPLEXITY" == "large" ]]; then
  MAX_LINES=500
else
  MAX_LINES=200  # medium
fi

if [[ $DIFF_LINES -gt $MAX_LINES ]]; then
  SCORE=$((SCORE - 2))
  FAILURES="${FAILURES}Diff too large: $DIFF_LINES lines (max $MAX_LINES for $TASK_COMPLEXITY task)\n"
  echo "⚠️  Diff size: $DIFF_LINES lines exceeds threshold ($MAX_LINES)"
fi

# Clamp to 0-10
[[ $SCORE -lt 0 ]] && SCORE=0
[[ $SCORE -gt 10 ]] && SCORE=10

# Save results
echo "$SCORE" > "$RESULTS_DIR/quality_score"
cat > "$RESULTS_DIR/quality_report.txt" << EOF
Quality Gate Report
===================
Score: $SCORE/10

Criteria:
- File Scope: $([[ $UNEXPECTED -eq 0 && $MISSING -eq 0 ]] && echo "PASS" || echo "FAIL") ($UNEXPECTED unexpected, $MISSING missing)
- Validation: $([[ $VALIDATION_FAILED -eq 0 ]] && echo "PASS" || echo "FAIL")
- Diff Size: $DIFF_LINES lines $([[ $DIFF_LINES -le $MAX_LINES ]] && echo "(PASS)" || echo "(FAIL - max $MAX_LINES)")

Failures:
${FAILURES:-None}

Modified Files:
$(git diff --name-only 2>/dev/null || echo "N/A")
EOF

# Decision
echo ""
echo "╔════════════════════════════════════╗"
echo "║     QUALITY GATE: $SCORE/10        ║"
echo "╚════════════════════════════════════╝"

if [[ $SCORE -ge 6 ]]; then
  echo "✅ ACCEPT: Changes meet quality threshold"
  exit 0
else
  echo "❌ REJECT: Changes below quality threshold"
  echo "   Options:"
  echo "   1. Retry subagent with error context"
  echo "   2. Do task inline (parent handles it)"
  exit 1
fi

Usage in Wave Execution

# After collecting subagent results
for id in "${TASK_NAMES[@]}"; do
  # Run quality gate on each subagent's output
  if quality-gate.sh "$TMPDIR/$id-worktree" "$RESULTS_DIR" "${TASK_WRITES[$id]}" "medium"; then
    # Merge changes
    git merge "subagent/$id" --no-edit
  else
    # Retry once, then abandon
    FAILED_TASKS+=("$id")
  fi
done

# Only proceed if all tasks passed quality gate
if [[ ${#FAILED_TASKS[@]} -gt 0 ]]; then
  echo "❌ Wave failed quality gate for: ${FAILED_TASKS[*]}"
  # Retry or handle inline
fi

Decision Matrix

Score	Action
10	Perfect - merge immediately
8-9	Good - merge with note
6-7	Acceptable - merge, monitor next wave
5	Borderline - retry with context
<5	Reject - retry once, then do inline

Integration with Retry

When retrying a failed quality gate:

retry_with_quality_context() {
  local id="$1"
  local original_prompt="$2"
  local quality_report=$(cat "$RESULTS_DIR/$id/quality_report.txt")
  
  RETRY_PROMPT="$original_prompt

QUALITY GATE FAILED (Score: $(cat $RESULTS_DIR/$id/quality_score)/10)

Issues to fix:
$quality_report

Please address these issues and ensure:
1. Only modify the declared target files
2. All validation passes (typecheck, lint, tests)
3. Keep changes focused and proportional to the task"

  # Retry with enhanced prompt
  timeout 300 $AGENT_CMD "$RETRY_PROMPT" > "$TMPDIR/$id.retry.out" 2>&1
}

Rules

1. Score < 6 = Reject - Don't merge low-quality changes
2. Retry once - Give subagent a chance to fix with context
3. After 2 failures, do inline - Parent takes over
4. Log all scores - Track quality trends across waves
5. Fail fast - Reject early, don't waste time on bad output

4g. Cost & Budget Management

Prevent runaway costs by tracking token usage and enforcing budgets.

Subagent fans-out can quickly consume credits if unchecked. Use the cost tracker to monitor spend.

Budget Tiers

Tier	Task Type	Model Class	Cap
L1	Research	Haiku/Mini	$0.01
L2	Edit	Sonnet/GPT-4o	$0.05
L3	Architect	Opus/o1	$0.50

Implementation

Use skill/cost-tracker.sh in your loop:

source skill/cost-tracker.sh

# Check budget before spawning
if ! check_budget; then
  echo "Budget exceeded!"
  exit 1
fi

# Track after completion
track_usage "claude-3-sonnet" $INPUT_TOKS $OUTPUT_TOKS "$TASK_ID"

See skill/references/cost-management.md for full details.

4h. Proceed to next wave

Clear PIDs, spawn the next wave's tasks (whose dependencies are now met), repeat 4a-4f.

Advanced Patterns

See references/orchestration.md for:

• Git worktree isolation (parallel writes to overlapping files)
• Chained pipelines (researcher → planner → executor)
• Structured JSON output collection and manifests
• Throttle governors and resource limits
• Streaming results as they complete

Rules

1. Discover, don't assume — always check --help before using any CLI flags.
2. Max 6 concurrent subagents — more causes resource contention.
3. Always timeout — timeout 300 (5 min) default, adjust per task complexity.
4. Disjoint writes only — never let two subagents write the same file in the same wave.
5. Verify every wave — run typecheck/tests/lint before proceeding.
6. Full context in every prompt — subagents have zero memory of the parent session.
7. Retry once, then do it yourself — don't retry-loop.
8. Prefer fewer, larger tasks — process spawn overhead is real.