FreeAPITools for AI Agents

Discovery files

• /llms.txt — concise index of pages, designed for LLM ingestion
• /llms-full.txt — full bundle with every endpoint documented inline
• /openapi.json — OpenAPI 3.1 specification
• /api-catalog.json — JSON catalog of every endpoint
• /.well-known/mcp.json — Model Context Protocol manifest
• /.well-known/ai-plugin.json — OpenAI/ChatGPT plugin manifest
• /.well-known/ai-agents.json — agent compatibility manifest
• /sitemap-index.xml — full sitemap

Compatible clients

Integration in 4 lines

# 1. Get the catalog
curl https://freeapitools.dev/api-catalog.json

# 2. Register (no email, no card)
curl -X POST https://freeapitools.dev/api/v1/register \
  -H "Content-Type: application/json" \
  -d '{"app_name":"my-agent","platform":"node"}'

# 3. Activate
curl -X POST https://freeapitools.dev/api/v1/activate \
  -H "Content-Type: application/json" \
  -d '{"api_key":"YOUR_KEY","client":{"name":"my-agent","type":"sdk","version":"1.0"}}'

# 4. Call any endpoint
curl "https://freeapitools.dev/api/v1/weather?city=London" \
  -H "X-API-Key: YOUR_KEY"

Categories (20)

Why agents pick FreeAPITools

• • Deterministic JSON output — no HTML scraping
• • Stable URLs — endpoints versioned under /api/v1/*
• • Free tier on every endpoint — no billing setup
• • Single auth model — one API key for all 500+ APIs
• • Full OpenAPI 3.1 + llms-full.txt for one-shot ingestion
• • Native MCP transport at /api/v1/mcp