OpenClaw API Explained — How to Integrate and Extend OpenClaw

OpenClaw exposes a local REST API and webhook endpoint system that lets you trigger agent actions from external applications, integrate with other tools, and build custom workflows that extend beyond what the built-in channels support.

The OpenClaw Local API

When the gateway is running, it exposes a local HTTP API on port 3000 (configurable). This API lets you:

• Send messages to your agent programmatically
• Trigger specific skills or tasks
• Query agent status
• Manage crons and channels via API instead of CLI

Base URL and Authentication

# Default base URL:
http://localhost:3000/api

# Authentication via API key (set in openclaw.json):
{
  "api": {
    "enabled": true,
    "key": "your-api-key-here",
    "port": 3000
  }
}

# All requests require header:
Authorization: Bearer your-api-key-here

Sending Messages to Your Agent

# POST /api/messages
curl -s -X POST http://localhost:3000/api/messages \
  -H "Authorization: Bearer YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{"content": "Summarize this week revenue from Stripe", "channel": "api"}'

# Agent processes the task and returns response:
{"id": "msg_abc123", "response": "This week revenue...", "status": "completed"}

Webhook Endpoints

OpenClaw can expose webhook endpoints that trigger agent tasks when external services call them:

# Configure webhooks in openclaw.json:
{
  "webhooks": [
    {
      "path": "/webhook/stripe",
      "secret": "whsec_your_stripe_secret",
      "task": "A Stripe event arrived. Parse the webhook payload and handle it: for payment.succeeded, update the customer record. For subscription.cancelled, send a win-back email."
    },
    {
      "path": "/webhook/github",
      "task": "A GitHub event arrived. If it's a PR opened, post a summary to #saas Slack. If a PR is merged, post the commit message."
    }
  ]
}

Triggering Crons via API

# Run a cron job immediately:
curl -s -X POST http://localhost:3000/api/crons/hex-daily-brief/run \
  -H "Authorization: Bearer YOUR_KEY"

# List cron status:
curl -s http://localhost:3000/api/crons \
  -H "Authorization: Bearer YOUR_KEY"

External Integration Pattern

Common pattern: external app calls OpenClaw API → agent processes → agent posts result to Slack:

# From any application:
fetch('http://your-server:3000/api/messages', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    content: `New support ticket: ${ticketContent}. Categorize and draft a response.`,
    channel: 'api'
  })
})

Exposing to the Internet

To receive webhooks from external services, expose your OpenClaw API via your domain:

# Nginx proxy config:
server {
  server_name api.yourdomain.com;
  location / {
    proxy_pass http://localhost:3000;
    proxy_set_header Host $host;
  }
}

# Then configure your webhook URL:
# https://api.yourdomain.com/webhook/stripe

Get the complete setup guide in The OpenClaw Playbook — everything you need to master OpenClaw for $9.99.