Secure Low-Latency Interactive Messaging

part of

The secure transport layer for A2A, MCP, and SLIMRPC.

SLIM is built for interactive agent workloads: low-latency, end-to-end encrypted message delivery between agents that may be co-located or continents apart. Where protocols define conversation semantics, SLIM provides the data plane that makes those conversations work in production.

See SLIM in Action Community GitHub

Why Use SLIM

Transport for Agent Protocols

Carry A2A, MCP, OpenTelemetry, and custom agent protocols over a single secure overlay instead of bespoke per-protocol networking.

End-to-End Encryption

Message Layer Security (MLS) keeps payloads encrypted from source to destination, even when traffic traverses shared routing infrastructure.

Network-Topology Independence

Agents connect outbound to SLIM nodes—reachable by name, without exposing every agent to the internet.

How SLIM Routes Messages

See SLIM in Action

user@slim:~

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Start Node Send a Message

Community

Connect with AGNTCY contributors, join working group meetings, and help shape secure agent messaging. For more information, see the community page.

Discord Chat with maintainers and contributors in the AGNTCY Discord server. Meetings Join working group and community meetings on the AGNTCY calendar. Blog Read announcements, tutorials, and technical deep dives from the SLIM team.

Contribute

Help build SLIM by contributing code, reporting bugs, or suggesting enhancements. Pick up a good first issue, review open pull requests, or read the contributing guide to get started.

Visit our GitHub Good first issues

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Explore SLIM

• Read the Introduction

  Understand core concepts, the messaging layer, and the controller.

  Overview

• Get Started

  Run a SLIM node and send your first messages in minutes.

  Getting Started

• Dive into the Specification

  Explore the SLIM Internet Draft and protocol definition.

  SLIM Specification

• Integrations

  Run A2A, MCP, SLIMRPC, and OpenTelemetry over SLIM.

  Integrations

• Data Plane Config Reference

  Tune the data plane for your environment.

  Configuration Reference

• Controller Config Reference

  Controller API and configuration details.

  Controller Reference

• Join the Community

  Connect with maintainers and contributors across the AGNTCY project.

  SLIM Community