Tamper-evident, third-party-verifiable receipts for AI agent / MCP tool calls. Hash-chain (zero-dep) + Ed25519 signatures + external-mediator mode + verifier CLI + a tamper-evident-memory integration with mnemo. pip install agora-agent-receipts. Reference PoC — credits the 'Agent Receipts' protocol (Otto Jongerius), Microsoft agent-governance-toolkit, pipelock, and the arXiv work in this space. Code: /agent-receipts. MIT.