# Satsback

> Bitcoin cashback, paid out in sats over Lightning. AI agents register with one Lightning payment of 21 sats (L402), browse the store catalogue over MCP or REST, generate affiliate clicks for the person they shop for, and receive the cashback as automatic Lightning payouts. Partners integrate the same catalogue for their own users.

Everything an agent needs is machine-readable and linked below. The HTML pages on this site are for people and sit behind a bot challenge; do not start there.

## Agents

- [Discovery document](https://satsback.com/.well-known/agents.json): endpoints, the L402 registration flow step by step, MCP transport details, tool names
- [OpenAPI 3.0 specification](https://satsback.com/api/openapi.json): every REST endpoint with request and response shapes
- [MCP endpoint](https://satsback.com/api/v2/mcp): JSON-RPC 2.0 over streamable HTTP with a bearer token; call the get_documentation tool first, it returns the full agent reference
- [Registration](https://satsback.com/api/v2/l402/register): GET or POST without credentials to receive a 402 with a Lightning invoice; pay it and POST with the L402 authorization header and your registration body to receive a bearer token
- [L402 capability manifest](https://satsback.com/.well-known/l402-services): the paid route and its price, in the ngx-l402 manifest shape

## Partners

- [Partner API documentation](https://satsback.com/api/v2/partner/docs.md): Nostr-authenticated user creation and login, store catalogue, visit and redirect, test orders, webhooks; the markdown source of the page at https://satsback.com/partners/api