---
name: parallel-agents
description: Parallel Agent Orchestration
user-invocable: false
---
# Parallel Agent Orchestration
When launching multiple agents in parallel, follow this pattern to avoid context bloat.
## Core Principles
1. **No TaskOutput calls** - TaskOutput returns full agent output, bloating context
2. **Run in background** - Always use `run_in_background: true`
3. **File-based confirmation** - Agents write status to files, not return values
4. **Append, don't overwrite** - Multiple agents can write to same status file
## Output Patterns
### Simple Confirmation (parallel batch work)
For tasks where agents just need to confirm completion:
```bash
# Agent writes to shared status file
echo "COMPLETE: <task-name> - $(date)" >> .claude/cache/<batch-name>-status.txt
```
- Use `>>` to append (not `>` which overwrites)
- Include timestamp for ordering
- One line per agent completion
- Check with: `cat .claude/cache/<batch-name>-status.txt`
### Detailed Output (research/exploration)
For tasks requiring detailed findings:
```
.claude/cache/agents/<task-type>/<agent-id>/
├── output.md # Main findings
├── artifacts/ # Any generated files
└── status.txt # Completion confirmation
```
- Each agent gets own directory
- Full output preserved for later reading
- Status file still used for quick completion check
## Task Prompt Template
```markdown
# Task: <TASK_NAME>
## Your Mission
<clear objective>
## Output
When done, write confirmation:
\`\`\`bash
echo "COMPLETE: <identifier> - $(date)" >> .claude/cache/<batch>-status.txt
\`\`\`
Do NOT return large output. Complete work silently.
```
## Launching Pattern
```typescript
// Launch all in single message block (parallel)
Task({
description: "Task 1",
prompt: "...",
subagent_type: "general-purpose",
run_in_background: true
})
Task({
description: "Task 2",
prompt: "...",
subagent_type: "general-purpose",
run_in_background: true
})
// ... up to 15 parallel agents
```
## Monitoring
```bash
# Check completion status
cat .claude/cache/<batch>-status.txt
# Count completions
wc -l .claude/cache/<batch>-status.txt
# Watch for updates
tail -f .claude/cache/<batch>-status.txt
```
## Batch Size
- **Max 15 agents** per parallel batch
- Wait for batch to complete before launching next
- Use status file to track which completed
## DO
- Use `run_in_background: true` always
- Have agents write to status files
- Use append (`>>`) not overwrite (`>`)
- Give each agent clear, self-contained instructions
- Include all context in prompt (agents don't share memory)
## DON'T
- Call TaskOutput (bloats context)
- Return large outputs from agents
- Launch more than 15 at once
- Rely on agent return values for orchestration
## Example: Provider Backfill
```bash
# Status file
.claude/cache/provider-backfill-status.txt
# Each agent appends on completion
echo "COMPLETE: anthropic - Thu Jan 2 12:34:56 2025" >> .claude/cache/provider-backfill-status.txt
echo "COMPLETE: openai - Thu Jan 2 12:35:12 2025" >> .claude/cache/provider-backfill-status.txt
```
Check progress:
```bash
cat .claude/cache/provider-backfill-status.txt
# COMPLETE: anthropic - Thu Jan 2 12:34:56 2025
# COMPLETE: openai - Thu Jan 2 12:35:12 2025
```