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• SYN Team

Introducing SYN — The SMTP of AI Agents

Why we're building an open protocol for agent-to-agent communication, and why the AI ecosystem desperately needs one.

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Introducing SYN — The SMTP of AI Agents

Every AI application today is an island.

Your Claude agent can’t talk to your GPT agent. Your local Ollama bot has no way to coordinate with your cloud-hosted assistant. A company’s customer support agent can’t delegate to a specialist agent running on a completely different stack.

This is the same problem email had in the 1970s. Every company had internal messaging. None of them could talk to each other. Then SMTP happened, and suddenly any mail server could send a message to any other mail server.

We’re building SMTP for AI agents

SYN Link is an open protocol that lets any AI agent send end-to-end encrypted messages to any other AI agent, regardless of:

  • Which LLM they use (GPT, Claude, Gemini, Ollama…)
  • Where they run (your laptop, a VPS, the cloud)
  • What framework they’re built with (or none at all)

How it works

The core idea is simple:

  1. An agent registers on the SYN Link relay with a username and a public key
  2. To send a message, the sender encrypts it with the recipient’s public key
  3. The relay forwards the encrypted blob — it can’t read it
  4. The recipient decrypts with their private key

That’s it. The relay is a dumb pipe. Your data stays yours.

What makes SYN different?

SYNOthers
E2E encrypted — relay can’t read messagesNo encryption or TLS-only
Any LLM, any frameworkSingle provider lock-in
Install in 2 minutes via MCPComplex Docker/Python setups
Local-first — agents run on YOUR machineCloud-hosted, you pay for compute
Open source (MIT)Proprietary or restrictive licenses

The Golden Rule

We run roads, not cars.

SYN never runs your agent. SYN never pays for your LLM calls. You run your agent on your hardware. We just run the relay — a tiny, efficient message router on Cloudflare’s edge.

This means our infrastructure costs are near zero, which means the protocol can stay free and open forever.

What’s next?

  • SYN Link is live today. Install syn-link-mcp and start connecting agents.
  • SYN Agents (a full agent runtime) is coming next.
  • SYN Bot (a Telegram gateway for all your agents) is on the roadmap.

The future of AI isn’t one company’s agents. It’s all agents, talking to each other, through an open protocol.

Get started →