Swarm

Swarm Skill

Spawn N coordinated agents working on a shared task list with SQLite-based atomic claiming. Like a dev team tackling multiple files in parallel—fast, reliable, and with full fault tolerance.

Usage

/swarm N:agent-type "task description"

Parameters

• N - Number of agents (1-5, enforced by Gemini CLI limit)
• agent-type - Agent to spawn (e.g., executor, build-fixer, architect)
• task - High-level task to decompose and distribute

Examples

/swarm 5:executor "fix all TypeScript errors"
/swarm 3:build-fixer "fix build errors in src/"
/swarm 4:designer "implement responsive layouts for all components"
/swarm 2:architect "analyze and document all API endpoints"

Architecture

User: "/swarm 5:executor fix all TypeScript errors"
              |
              v
      [SWARM ORCHESTRATOR]
              |
   +--+--+--+--+--+
   |  |  |  |  |
   v  v  v  v  v
  E1 E2 E3 E4 E5
   |  |  |  |  |
   +--+--+--+--+
          |
          v
    [SQLITE DATABASE]
    ┌─────────────────────┐
    │ tasks table         │
    ├─────────────────────┤
    │ id, description     │
    │ status (pending,    │
    │   claimed, done,    │
    │   failed)           │
    │ claimed_by, claimed_at
    │ completed_at, result│
    │ error               │
    ├─────────────────────┤
    │ heartbeats table    │
    │ (agent monitoring)  │
    └─────────────────────┘

Key Features:

• SQLite transactions ensure only one agent can claim a task
• Lease-based ownership with automatic timeout and recovery
• Heartbeat monitoring for detecting dead agents
• Full ACID compliance for task state

Workflow

1. Parse Input

• Extract N (agent count)
• Extract agent-type
• Extract task description
• Validate N <= 5

2. Create Task Pool

• Analyze codebase based on task
• Break into file-specific subtasks
• Initialize SQLite database with task pool
• Each task gets: id, description, status (pending), and metadata columns

3. Spawn Agents

• Launch N agents via Task tool
• Set run_in_background: true for all
• Each agent connects to the SQLite database
• Agents enter claiming loop automatically

3.1. Agent Preamble (IMPORTANT)

When spawning swarm agents, ALWAYS wrap the task with the worker preamble to prevent recursive sub-agent spawning:

import { wrapWithPreamble } from '../agents/preamble.js';

// When spawning each agent:
const agentPrompt = wrapWithPreamble(`
Connect to swarm at ${cwd}/.omc/state/swarm.db
Claim tasks with claimTask('agent-${n}')
Complete work with completeTask() or failTask()
Send heartbeat every 60 seconds
Exit when hasPendingWork() returns false
`);

Task({
  subagent_type: 'oh-my-gemini:executor',
  prompt: agentPrompt,
  run_in_background: true
});

The worker preamble ensures agents:

• Execute tasks directly using tools (Read, Write, Edit, Bash)
• Do NOT spawn sub-agents (prevents recursive agent storms)
• Report results with absolute file paths

4. Task Claiming Protocol (SQLite Transactional)

Each agent follows this loop:

LOOP:
  1. Call claimTask(agentId)
  2. SQLite transaction:
     - Find first pending task
     - UPDATE status='claimed', claimed_by=agentId, claimed_at=now
     - INSERT/UPDATE heartbeat record
     - Atomically commit (only one agent succeeds)
  3. Execute task
  4. Call completeTask(agentId, taskId, result) or failTask()
  5. GOTO LOOP (until hasPendingWork() returns false)

Atomic Claiming Details:

• SQLite IMMEDIATE transaction prevents race conditions
• Only agent updating the row successfully gets the task
• Heartbeat automatically updated on claim
• If claim fails (already claimed), agent retries with next task
• Lease Timeout: 5 minutes per task
• If timeout exceeded + no heartbeat, cleanupStaleClaims releases task back to pending

5. Heartbeat Protocol

• Agents call heartbeat(agentId) every 60 seconds (or custom interval)
• Heartbeat records: agent_id, last_heartbeat timestamp, current_task_id
• Orchestrator runs cleanupStaleClaims every 60 seconds
• If heartbeat is stale (>5 minutes old) and task claimed, task auto-releases

6. Progress Tracking

• Orchestrator monitors via TaskOutput
• Shows live progress: pending/claimed/done/failed counts
• Active agent count via getActiveAgents()
• Reports which agent is working on which task via getAgentTasks()
• Detects idle agents (all tasks claimed by others)

7. Completion

Exit when ANY of:

• isSwarmComplete() returns true (all tasks done or failed)
• All agents idle (no pending tasks, no claimed tasks)
• User cancels via /oh-my-gemini:cancel

Storage

SQLite Database (.omc/state/swarm.db)

The swarm uses a single SQLite database stored at .omc/state/swarm.db. This provides:

• ACID compliance - All task state transitions are atomic
• Concurrent access - Multiple agents query/update safely
• Persistence - State survives agent crashes
• Query efficiency - Fast status lookups and filtering

tasks Table Schema

CREATE TABLE tasks (
  id TEXT PRIMARY KEY,
  description TEXT NOT NULL,
  status TEXT NOT NULL DEFAULT 'pending',
    -- pending: waiting to be claimed
    -- claimed: claimed by an agent, in progress
    -- done: completed successfully
    -- failed: completed with error
  claimed_by TEXT,                  -- agent ID that claimed this task
  claimed_at INTEGER,               -- Unix timestamp when claimed
  completed_at INTEGER,             -- Unix timestamp when completed
  result TEXT,                      -- Optional result/output from task
  error TEXT                        -- Error message if task failed
);

heartbeats Table Schema

CREATE TABLE heartbeats (
  agent_id TEXT PRIMARY KEY,
  last_heartbeat INTEGER NOT NULL,  -- Unix timestamp of last heartbeat
  current_task_id TEXT              -- Task agent is currently working on
);

session Table Schema

CREATE TABLE session (
  id TEXT PRIMARY KEY,
  agent_count INTEGER NOT NULL,
  started_at INTEGER NOT NULL,
  completed_at INTEGER,
  active INTEGER DEFAULT 1
);

Task Claiming Protocol (Detailed)

Atomic Claim Operation with SQLite

The core strength of the new implementation is transactional atomicity:

function claimTask(agentId: string): ClaimResult {
  // Transaction ensures only ONE agent succeeds
  const claimTransaction = db.transaction(() => {
    // Step 1: Find first pending task
    const task = db.prepare(
      'SELECT id, description FROM tasks WHERE status = "pending" ORDER BY id LIMIT 1'
    ).get();

    if (!task) {
      return { success: false, reason: 'No pending tasks' };
    }

    // Step 2: Attempt claim (will only succeed if status is still 'pending')
    const result = db.prepare(
      'UPDATE tasks SET status = "claimed", claimed_by = ?, claimed_at = ? WHERE id = ? AND status = "pending"'
    ).run(agentId, Date.now(), task.id);

    if (result.changes === 0) {
      // Another agent claimed it between SELECT and UPDATE - try next
      return { success: false, reason: 'Task was claimed by another agent' };
    }

    // Step 3: Update heartbeat to show we're alive and working
    db.prepare(
      'INSERT OR REPLACE INTO heartbeats (agent_id, last_heartbeat, current_task_id) VALUES (?, ?, ?)'
    ).run(agentId, Date.now(), task.id);

    return { success: true, taskId: task.id, description: task.description };
  }).immediate();  // Explicitly acquire RESERVED lock for immediate transaction

  return claimTransaction();  // Atomic execution
}

Why SQLite Transactions Work:

• Transactions are called with .immediate() to acquire RESERVED lock
• Prevents other agents from modifying rows between SELECT and UPDATE
• All-or-nothing atomicity: claim succeeds completely or fails completely
• No race conditions, no lost updates

Lease Timeout & Auto-Release

Tasks are automatically released if claimed too long without heartbeat:

function cleanupStaleClaims(leaseTimeout: number = 5 * 60 * 1000) {
  // Default 5-minute timeout
  const cutoffTime = Date.now() - leaseTimeout;

  const cleanupTransaction = db.transaction(() => {
    // Find claimed tasks where:
    // 1. Claimed longer than timeout, OR
    // 2. Agent hasn't sent heartbeat in that time
    const staleTasks = db.prepare(`
      SELECT t.id
      FROM tasks t
      LEFT JOIN heartbeats h ON t.claimed_by = h.agent_id
      WHERE t.status = 'claimed'
        AND t.claimed_at < ?
        AND (h.last_heartbeat IS NULL OR h.last_heartbeat < ?)
    `).all(cutoffTime, cutoffTime);

    // Release each stale task back to pending
    for (const staleTask of staleTasks) {
      db.prepare('UPDATE tasks SET status = "pending", claimed_by = NULL, claimed_at = NULL WHERE id = ?')
        .run(staleTask.id);
    }

    return staleTasks.length;
  }).immediate();  // Explicitly acquire RESERVED lock for immediate transaction

  return cleanupTransaction();
}

How Recovery Works:

1. Orchestrator calls cleanupStaleClaims() every 60 seconds
2. If agent hasn't sent heartbeat in 5 minutes, task is auto-released
3. Another agent picks up the orphaned task
4. Original agent can continue working (it doesn't know it was released)
5. When original agent tries to mark task as done, verification fails safely

API Reference

Agents interact with the swarm via a TypeScript API:

Initialization

import { startSwarm, connectToSwarm } from './swarm';

// Orchestrator starts the swarm
await startSwarm({
  agentCount: 5,
  tasks: ['fix a.ts', 'fix b.ts', ...],
  leaseTimeout: 5 * 60 * 1000,      // 5 minutes (default)
  heartbeatInterval: 60 * 1000      // 60 seconds (default)
});

// Agents join existing swarm
await connectToSwarm(process.cwd());

Agent Loop Pattern

import {
  claimTask,
  completeTask,
  failTask,
  heartbeat,
  hasPendingWork,
  disconnectFromSwarm
} from './swarm';

const agentId = 'agent-1';

// Main work loop
while (hasPendingWork()) {
  // Claim next task
  const claim = claimTask(agentId);

  if (!claim.success) {
    console.log('No tasks available:', claim.reason);
    break;
  }

  const { taskId, description } = claim;
  console.log(`Agent ${agentId} working on: ${description}`);

  try {
    // Do the work...
    const result = await executeTask(description);

    // Mark complete
    completeTask(agentId, taskId, result);
    console.log(`Agent ${agentId} completed task ${taskId}`);

  } catch (error) {
    // Mark failed
    failTask(agentId, taskId, error.message);
    console.error(`Agent ${agentId} failed on ${taskId}:`, error);
  }

  // Send heartbeat every 60 seconds (while working on long tasks)
  heartbeat(agentId);
}

// Cleanup
disconnectFromSwarm();

Core API Functions

startSwarm(config: SwarmConfig): Promise<boolean>

Initialize the swarm with task pool and start cleanup timer.

const success = await startSwarm({
  agentCount: 5,
  tasks: ['task 1', 'task 2', 'task 3'],
  leaseTimeout: 5 * 60 * 1000,
  heartbeatInterval: 60 * 1000
});

stopSwarm(deleteDatabase?: boolean): boolean

Stop the swarm and optionally delete the database.

stopSwarm(true);  // Delete database on cleanup

claimTask(agentId: string): ClaimResult

Claim the next pending task. Returns { success, taskId, description, reason }.

const claim = claimTask('agent-1');
if (claim.success) {
  console.log(`Claimed: ${claim.description}`);
}

completeTask(agentId: string, taskId: string, result?: string): boolean

Mark a task as done. Only succeeds if agent still owns the task.

completeTask('agent-1', 'task-1', 'Fixed the bug');

failTask(agentId: string, taskId: string, error: string): boolean

Mark a task as failed with error details.

failTask('agent-1', 'task-1', 'Could not compile: missing dependency');

heartbeat(agentId: string): boolean

Send a heartbeat to indicate agent is alive. Call every 60 seconds during long-running tasks.

heartbeat('agent-1');

cleanupStaleClaims(leaseTimeout?: number): number

Manually trigger cleanup of expired claims. Called automatically every 60 seconds.

const released = cleanupStaleClaims(5 * 60 * 1000);
console.log(`Released ${released} stale tasks`);

hasPendingWork(): boolean

Check if there are unclaimed tasks available.

if (!hasPendingWork()) {
  console.log('All tasks claimed or completed');
}

isSwarmComplete(): boolean

Check if all tasks are done or failed.

if (isSwarmComplete()) {
  console.log('Swarm finished!');
}

getSwarmStats(): SwarmStats | null

Get task counts and timing info.

const stats = getSwarmStats();
console.log(`${stats.doneTasks}/${stats.totalTasks} done`);

getActiveAgents(): number

Get count of agents with recent heartbeats.

const active = getActiveAgents();
console.log(`${active} agents currently active`);

getAllTasks(): SwarmTask[]

Get all tasks with current status.

const tasks = getAllTasks();
const pending = tasks.filter(t => t.status === 'pending');

getTasksWithStatus(status: string): SwarmTask[]

Filter tasks by status: 'pending', 'claimed', 'done', 'failed'.

const failed = getTasksWithStatus('failed');

getAgentTasks(agentId: string): SwarmTask[]

Get all tasks claimed by a specific agent.

const myTasks = getAgentTasks('agent-1');

retryTask(agentId: string, taskId: string): ClaimResult

Attempt to reclaim a failed task.

const retry = retryTask('agent-1', 'task-1');
if (retry.success) {
  console.log('Task reclaimed, trying again...');
}

Configuration (SwarmConfig)

interface SwarmConfig {
  agentCount: number;           // Number of agents (1-5)
  tasks: string[];              // Task descriptions
  agentType?: string;           // Agent type (default: 'executor')
  leaseTimeout?: number;        // Milliseconds (default: 5 min)
  heartbeatInterval?: number;   // Milliseconds (default: 60 sec)
  cwd?: string;                 // Working directory
}

Types

interface SwarmTask {
  id: string;
  description: string;
  status: 'pending' | 'claimed' | 'done' | 'failed';
  claimedBy: string | null;
  claimedAt: number | null;
  completedAt: number | null;
  error?: string;
  result?: string;
}

interface ClaimResult {
  success: boolean;
  taskId: string | null;
  description?: string;
  reason?: string;
}

interface SwarmStats {
  totalTasks: number;
  pendingTasks: number;
  claimedTasks: number;
  doneTasks: number;
  failedTasks: number;
  activeAgents: number;
  elapsedTime: number;
}

Key Parameters

• Max Agents: 5 (enforced by Gemini CLI background task limit)
• Lease Timeout: 5 minutes (default, configurable)
  • Tasks claimed longer than this without heartbeat are auto-released
• Heartbeat Interval: 60 seconds (recommended)
  • Agents should call heartbeat() at least this often
  • Prevents false timeout while working on long tasks
• Cleanup Interval: 60 seconds
  • Orchestrator automatically runs cleanupStaleClaims() to release orphaned tasks
• Database: SQLite (stored at .omc/state/swarm.db)
  • One database per swarm session
  • Survives agent crashes
  • Provides ACID guarantees

Error Handling & Recovery

Agent Crash

• Task is claimed but agent stops sending heartbeats
• After 5 minutes of no heartbeat, cleanupStaleClaims() releases the task
• Task returns to 'pending' status for another agent to claim
• Original agent's incomplete work is safely abandoned

Task Completion Failure

• Agent calls completeTask() but is no longer the owner (was released)
• The update silently fails (no agent matches in WHERE clause)
• Agent can detect this by checking return value
• Agent should log error and continue to next task

Database Unavailable

• startSwarm() returns false if database initialization fails
• claimTask() returns { success: false, reason: 'Database not initialized' }
• Check isSwarmReady() before proceeding

All Agents Idle

• Orchestrator detects via getActiveAgents() === 0 or hasPendingWork() === false
• Triggers final cleanup and marks swarm as complete
• Remaining failed tasks are preserved in database

No Tasks Available

• claimTask() returns success=false with reason 'No pending tasks available'
• Agent should check hasPendingWork() before looping
• Safe for agent to exit cleanly when no work remains

Cancel Swarm

User can cancel via /oh-my-gemini:cancel:

• Stops orchestrator monitoring
• Signals all background agents to exit
• Preserves partial progress in SQLite database
• Marks session as "cancelled" in database

Use Cases

1. Fix All Type Errors

/swarm 5:executor "fix all TypeScript type errors"

Spawns 5 executors, each claiming and fixing individual files.

2. Implement UI Components

/swarm 3:designer "implement Material-UI styling for all components in src/components/"

Spawns 3 designers, each styling different component files.

3. Security Audit

/swarm 4:security-reviewer "review all API endpoints for vulnerabilities"

Spawns 4 security reviewers, each auditing different endpoints.

4. Documentation Sprint

/swarm 2:writer "add JSDoc comments to all exported functions"

Spawns 2 writers, each documenting different modules.

Benefits of SQLite-Based Implementation

Atomicity & Safety

• Race-Condition Free: SQLite transactions guarantee only one agent claims each task
• No Lost Updates: ACID compliance means state changes are durable
• Orphan Prevention: Expired claims are automatically released without manual intervention

Performance

• Fast Queries: Indexed lookups on task status and agent ID
• Concurrent Access: Multiple agents read/write without blocking
• Minimal Lock Time: Transactions are microseconds, not seconds

Reliability

• Crash Recovery: Database survives agent failures
• Automatic Cleanup: Stale claims don't block progress
• Lease-Based: Time-based expiration prevents indefinite hangs

Developer Experience

• Simple API: Just claimTask(), completeTask(), heartbeat()
• Full Visibility: Query any task or agent status at any time
• Easy Debugging: SQL queries show exact state without decoding JSON

Scalability

• 10s to 1000s of Tasks: SQLite handles easily
• Full Task Retention: Complete history in database for analysis
• Extensible Schema: Add custom columns for task metadata

STATE CLEANUP ON COMPLETION

IMPORTANT: Delete state files on completion - do NOT just set active: false

When all tasks are done:

# Delete swarm state files
rm -f .omc/state/swarm-state.json
rm -f .omc/state/swarm-tasks.json
rm -f .omc/state/swarm-claims.json

Implementation Notes

The orchestrator (main skill handler) is responsible for:

1. Initial task decomposition (via explore/architect)
2. Creating and initializing SQLite database via startSwarm()
3. Spawning N background agents
4. Monitoring progress via getSwarmStats() and getActiveAgents()
5. Running cleanupStaleClaims() automatically (via setInterval)
6. Detecting completion via isSwarmComplete()
7. Reporting final summary from database query

Each agent is a standard Task invocation with:

• run_in_background: true
• Agent-specific prompt with work loop instructions
• API import: import { claimTask, completeTask, ... } from './swarm'
• Connection: await connectToSwarm(cwd) to join existing swarm
• Loop: repeatedly call claimTask() → do work → completeTask() or failTask()