# Agent interop :: Winthropic

Every number on this site is one request away for a machine. Human pages have a markdown mirror at the same path with .md appended, or send Accept: text/markdown.

## Endpoints

- Public API: GET https://winthropic.com/api/index.json (run dates, per-model series, latest deltas; free, no key). Full run records at https://winthropic.com/api/runs/<date>.json.
- MCP server: https://winthropic.com/mcp (Streamable HTTP). Tools: index_summary, list_runs, get_run, model_series, audit_usage. Add with: claude mcp add --transport http winthropic https://winthropic.com/mcp
- llms.txt: https://winthropic.com/llms.txt and https://winthropic.com/llms-full.txt
- OpenAPI: https://winthropic.com/openapi.json
- L402 gateway: Lightning invoices via phoenixd at pay.winthropic.com; 19,000 sats for the Token Audit. Stripe Checkout is the dollar rail ($19).
- Feeds: https://winthropic.com/feed.xml (RSS) and https://winthropic.com/feed.json (JSON Feed)

## Buying the Token Audit as a machine

1. POST a usage CSV (text/csv, or JSON {"csv": "..."}) to https://winthropic.com/api/audit.
2. If identified savings are under $19, the response is 200 with the full findings and fee_declined: true. Otherwise it is 402 with a teaser, a guarantee object, and payment rails: a Lightning invoice (www-authenticate: L402 invoice="...") and a Stripe Checkout URL.
3. Pay the invoice, then GET https://winthropic.com/api/audit/<report_id> with Authorization: L402 <payment_hash>:<preimage>. After Stripe, GET the same resource with ?session_id=<checkout session>.
4. The 200 body is {report_id, paid: true, analysis}. Reports expire 60 days after creation.

The playground on https://winthropic.com/interop simulates this exchange client-side with placeholder invoice and preimage values; no funds move.