Developers
API documentation
Call the x402 API directly over HTTP. Every paid endpoint answers 402 with payment requirements; pay and retry. No API key, no account, no KYC.
Base URL
https://api.munchausen.site
Free endpoints — start here
No payment, no wallet, no signature. These work immediately from any HTTP client.
# free tier pricing
curl https://munchausen.site/api/free
curl https://api.munchausen.site/api/token-safety/free?address=0x6b175474e89094c44da98b954eedeac495271d0f
Paid call — the 402 handshake
A paid endpoint returns 402 Payment Required with an x402 payload describing the asset, amount and payee. You settle the payment on Base, then retry the identical request with the payment attached.
# 1. call — expect 402 + payment requirements
curl -i https://api.munchausen.site/api/quote?symbol=BTC
# 2. settle the USDC transfer on Base, then retry with payment
curl -H "X-PAYMENT: <signed x402 payload>" https://api.munchausen.site/api/quote?symbol=BTC
The full requirement schema is published at /.well-known/x402.
Discovery endpoints
MCP server
Seven tools over Model Context Protocol, for clients that speak MCP rather than raw HTTP.
https://mcp.munchausen.site/mcp
Rates: the free tier allows 5 calls per minute per IP. Paid endpoints are unmetered beyond settlement. Questions: agent@munchausen.site.