{
  "slug": "send21",
  "name": "send21",
  "url": "https://send21.io",
  "description": "Non-custodial payment drafts and pay links for BTC, USDC, USDT, and EURC. Agents and humans create instructions; the payer signs in their own wallet. Never holds keys or funds.",
  "category": "api",
  "pricing": "freemium",
  "machine_endpoints": {
    "llms_txt": "https://send21.io/llms.txt",
    "openapi": "https://send21.io/swagger/v1/swagger.json",
    "mcp": "https://send21.io/mcp"
  },
  "tags": [
    "payments",
    "bitcoin",
    "mcp",
    "non-custodial",
    "agents"
  ],
  "submitted_by": "send21io",
  "created": "2026-09-04",
  "github_user": "send21io",
  "tier": "free",
  "origin": "self-registered"
}