agent-mesh

Cryptographic peer-to-peer agent coordination.

No broker. No scp'd tokens. No centralized configuration.

A small Rust workspace that gives multi-agent systems a shared root of trust (ed25519 user key, cross-signed by your existing GitHub SSH key) and direct, verifiable peer messaging.

Two agents that share a user identity discover each other on the LAN, authenticate via cert chain at the QUIC handshake, and exchange signed envelopes — without a broker in the middle and without scp'ing tokens around.

CLI: amesh (workspace member agent-mesh-cli). Libraries:

• agent-mesh-protocol — identity types, signed envelopes.
• agent-mesh-discovery — LAN discovery via mDNS.
• agent-mesh-transport — authenticated QUIC transport via iroh.
• agent-mesh-transport-ssh — AgentKey-authenticated sessions over OpenSSH.
• agent-mesh-bus — high-level pub/sub + request/reply.
• agent-mesh-py — Python bindings (PyPI package agent-mesh).

License: Apache-2.0.

Python install

pip install newt-agent-mesh

(The PyPI distribution name is newt-agent-mesh because agent-mesh is blocked by PyPI's similarity check — see the note in pyproject.toml. The Python import path is unchanged: import agent_mesh.core.)

This installs the Python package agent_mesh with submodules .core, .discovery, .transport, .bus, and puts a native-Python amesh on $PATH (agent_mesh.cli:main) with full subcommand parity with the Rust binary below — both operate on the same ~/.agent-mesh/ layout, so you can swap between them freely.

Rust install

The library crates are on crates.io:

# Cargo.toml
[dependencies]
agent-mesh-protocol = "0.7"   # ed25519 identity, signed envelopes
agent-mesh-discovery = "0.7"  # mDNS LAN discovery
agent-mesh-transport = "0.7"  # authenticated QUIC via iroh
agent-mesh-bus = "0.7"        # high-level pub/sub + request/reply

The amesh CLI:

cargo install agent-mesh-cli   # binary lands as `amesh` on PATH

(The -protocol suffix on the foundation crate is because agent-mesh-core on crates.io is owned by an unrelated project. The Rust crate name is agent-mesh-protocol; the Python user-facing submodule it powers is still agent_mesh.core.)

Discovery (Phase 1)

amesh can announce itself on the LAN and list every other agent it sees there, with no broker or central registry. Service type: _agent-mesh._udp.local.

# Terminal A — announce this agent for 5 minutes, advertising
# `ollama` and `vllm` capabilities under the role `inference-worker`.
amesh announce --capability ollama --capability vllm \
                --role inference-worker --duration 5m

# Terminal B — list everyone on the LAN for the next 5 seconds.
amesh peers --listen 5s

# Or only those sharing our user fingerprint:
amesh peers --listen 5s --same-user

Sample amesh peers output:

listening for peers for 5s...

discovered 2 peer(s):

AGENT          SAME?  ROLE@HOST                     PORT   CAPABILITIES
abcd12345678   yes    inference-worker@host-a       0      ollama,vllm
ef9876543210   no     orchestrator@host-b           0      orchestrator

The fingerprints in mDNS TXT records are claims; verification happens during the Phase 2 transport handshake (below).

Transport (Phase 2)

Phase 2 layers an authenticated QUIC transport on top of Phase 1 discovery. Two architectural notes:

• The agent's ed25519 signing key doubles as its iroh EndpointId, so a peer who knows your agent fingerprint already knows enough to address your iroh endpoint. No separate "node ID" to manage.
• After ALPN negotiation (agent-mesh/v1), both ends exchange cert chains and enforce the auto-team rule fail-closed: if peer user_pubkey != ours and no pact exists, the handshake rejects before any payload data crosses the boundary.

The CLI splits "I want to be discovered" from "I want to be reachable":

End-to-end smoke (same user on two terminals):

# Terminal A — bind QUIC, announce on mDNS, accept envelopes
amesh listen --duration 60s
# prints:
#   listening on udp/<port>
#     agent_fp=<fp>
#     user_fp =<user_fp>

# Terminal B — within that 60s window:
amesh send <fp-from-terminal-A> --payload '{"hello":"world"}'
# Terminal A then prints one JSON line per received envelope:
#   {"sender_agent_fp":"...","sender_user_fp":"...","sequence":0,
#    "payload":{"encoding":"utf8","text":"{\"hello\":\"world\"}"}}

If you point amesh send at a peer that belongs to a different user, the handshake closes the connection cleanly and both sides report auto-team check failed: ....

For networks reached through an SSH bastion, the optional agent-mesh-transport-ssh crate treats OpenSSH as a byte-stream carrier and runs a separate, mutually authenticated AgentKey session inside it. The inner session proves live possession, binds records to a fresh transcript, and is the only source of AuthenticatedPeer provenance; neither the SSH account nor a SignedEnvelope is treated as carrier identity. See the SSH transport decision record for the trust model and its explicit relay limitations.

Python Usage

Install the wheel:

pip install newt-agent-mesh

(See the install section above for why the distribution name is newt-agent-mesh and not agent-mesh. The import path is unchanged.)

Identity round-trip — no network required:

import agent_mesh.core as core

# Generate a user key (root of trust).
user = core.UserKey.generate()
print("user fp:", user.fingerprint().hex())

# Issue an agent key signed by that user.
meta = core.AgentMetadata(
    role="my-agent",
    host="my-machine",
    capabilities=["inference"],
    issued_at="2026-05-29T00:00:00Z",
)
agent = core.AgentKey.issue(user, meta)
print("agent fp:", agent.fingerprint().hex())

# Build and verify a signed envelope.
recipient = core.Recipient.topic("hello/world")
env = core.SignedEnvelope(agent, recipient, sequence=1, payload=b"hi")
env.verify()  # raises core.MeshError on tamper

Request/reply over an authenticated mesh — needs mDNS on the LAN:

import asyncio
import agent_mesh.core as core
import agent_mesh.bus as bus


async def main() -> None:
    user = core.UserKey.generate()
    meta = core.AgentMetadata(
        role="echo",
        host="localhost",
        capabilities=["test"],
        issued_at="2026-05-29T00:00:00Z",
    )
    server_agent = core.AgentKey.issue(user, meta)
    client_agent = core.AgentKey.issue(user, meta)

    server_bus = await bus.Bus.bind(user, server_agent, 0)
    client_bus = await bus.Bus.bind(user, client_agent, 0)

    topic = bus.Topic(user.fingerprint(), "echo")
    server_bus.handle_requests(topic, lambda body: b"echo: " + body)

    # Let mDNS settle.
    await asyncio.sleep(0.5)

    reply = await client_bus.request(
        server_bus.agent_fingerprint(),
        topic,
        b"hi",
        timeout_ms=5000,
    )
    print(reply)  # b'echo: hi'

    await server_bus.close()
    await client_bus.close()


asyncio.run(main())

The handler must return bytes directly. Async handlers (callables that return a coroutine) are recognized and rejected in this release; wrap any async work in asyncio.run(...) inside the sync handler.