CrawlerToll

Context License

Context License is the buyer-side discovery metadata format. A single JSON file a publisher serves from /.well-known/context-license.json declares price, license, payout, permitted use, and a signing key for response attestation. Agents read it before they make a request — to know what they're getting into.

It sits above the protocol layer (MCP / REST / OpenAPI) and below the marketplace layer.

How CrawlerToll uses it

The WordPress plugin writes and serves this file for you at https://your-domain/.well-known/context-license.json. It fills in your site name, domain, contact address, price and the payment schemes you have set up (x402 appears once you give a USDC payout address). You do not edit it by hand.

  • The License line the plugin adds to your robots.txt points at it. See RSL licence lines.
  • The unlock service fetches it when a site registers, as proof that the site is yours.
  • Agents read it to learn your price and terms before they ask.

Schema

{
  "$schema": "https://registry.crawlertoll.com/schemas/context-license/v1.json",
  "version": "1.0.0",
  "publisher": {
    "name": "Example Publisher",
    "slug": "example",
    "domain": "example.com",
    "contact": "ai@example.com"
  },
  "endpoints": [
    {
      "name": "search",
      "url": "https://example.com/mcp/search",
      "transport": "streamable-http",
      "description": "Search across our content corpus.",
      "schema_org_types": ["NewsArticle"]
    }
  ],
  "pricing": {
    "model": "per_query",
    "currency": "USD",
    "unit_price_micros": 5000
  },
  "auth": {
    "schemes": ["anonymous", "api_key", "x402"]
  },
  "terms_of_use": "https://example.com/ai-terms",
  "quality_signals": {
    "freshness_target_seconds": 86400,
    "last_updated": "2026-05-19T00:00:00Z"
  },
  "attestation": {
    "public_key_pem": "-----BEGIN PUBLIC KEY-----\n...\n-----END PUBLIC KEY-----",
    "kid": "ct_sign_example_2026-05",
    "algorithm": "ed25519"
  }
}

Optional fields

endpoints, terms_of_use and quality_signals are optional. A site that only sells sealed articles can leave endpoints out. When you do list an endpoint, transport can be "http" as well as "streamable-http".

Spec governance

The Context License spec is CC0. The maintainer (Charthouse Ltd) plans to donate the spec to a vendor-neutral standards body on the OpenAPI/SmartBear timeline (~month 9-12 post-publication). Until then, it sits openly governable by anyone.

See also