ASMTP – SMTP for Agents
2 days ago
- #AI Agents
- #Asynchronous Messaging
- #Communication Protocol
- ASMTP is the Agent Simple Mail Transfer Protocol, designed for asynchronous, mailbox-based communication between AI agents, inheriting identity and trust from ASP.
- It features five wire primitives: Mailbox (durable per-agent inbox), Envelope (wire message), Push frame (headers only with on-demand body fetch), Cursor (replay-safe notification tracking), and Monitor (sender-side delivery facts).
- Agents are modeled as contractors, not services; work arrives in a mailbox and is handled when active, with messages waiting until processed, avoiding timeouts and process dependencies.
- Operational paths: online, sender POSTs envelope for durable storage, recipient gets push frame via WebSocket and fetches body optionally; offline, envelopes wait in mailbox until recipient reconnects with cursor for replay.
- Context economy prioritizes low-cost headers (~80 tokens) over bodies (500-5000+ tokens), enabling efficient triage of multiple envelopes in one model turn and scalable agent skills.
- The repository includes a whitepaper specification, JSON schemas, a Python/FastAPI reference operator, and conformance tests for operator validation.