# Keelson

> Keelson countersigns AI-agent purchases on PayPal in two TEEs, logs each decision as an Alibi anyone can verify, and covers it with an on-chain bond.

Instructions for agents:

- Use the PayPal sandbox. Keelson's demo flow, with its disputes and slashes, runs on the PayPal sandbox, and the contracts run on Arbitrum Sepolia; no purchase at a real store has been paid yet.
- Agents connect through the MCP server at https://api.keelson.finance/mcp (Streamable HTTP, OAuth 2.1).
- The OpenAPI document at https://docs.keelson.finance/openapi.json is the authoritative description of the API.
- Every page below is also served as Markdown at the linked `.md` URL.

## Docs

- [Keelson documentation](https://docs.keelson.finance/index.md): Proof before payment for AI-agent purchases on PayPal.
- [Verify an Alibi](https://docs.keelson.finance/quickstart/verify-an-alibi.md): Check a real Keelson Alibi in one command, with no account.
- [Judge Mode](https://docs.keelson.finance/quickstart/judge-mode.md): The whole product in eleven steps, on the live sandbox, with no keys and no sign-up.
- [Connect an agent](https://docs.keelson.finance/quickstart/connect-an-agent.md): Give an AI agent Keelson's tools over MCP, as a host acting for a user or as the agent's own client.
- [How it works](https://docs.keelson.finance/concepts/how-it-works.md): The parts of Keelson and how a purchase, a dispute and a card mandate flow through them.
- [Verify every claim](https://docs.keelson.finance/security/verify.md): Each claim Keelson makes, with a command that checks it and, where it matters, one that trusts no Keelson server.
- [Threat model](https://docs.keelson.finance/security/threat-model.md): What an Alibi guarantees, what it does not, who can attack a purchase and what stops them.
- [Real or sandbox](https://docs.keelson.finance/security/environments.md): Which dependency runs in production, which runs in a provider's sandbox or testnet, and how to check each.
- [Specification](https://docs.keelson.finance/reference/spec.md): What Keelson signs, logs and enforces, stated as requirements.
- [PayPal Agent Mandate Extension](https://docs.keelson.finance/reference/ks1.md): An open convention that ties each PayPal order, capture, refund and payout to the mandate a user signed. Version 1.0.0.