# SLIM

> AGNTCY's secure, low-latency messaging substrate for agent-to-agent, human-in-the-loop and tool communication, designed for multi-modal exchange and quantum-safe security.

_The Agent Protocol Atlas · /protocols/slim · [JSON](/api/protocols/slim) · [all The Agent Protocol Atlas](/protocols)_

- **name:** SLIM
- **full_name:** Secure Low-latency Interactive Messaging
- **layer:** interop
- **creator:** AGNTCY project (Cisco / Outshift); Linux Foundation
- **status:** active (AGNTCY component)
- **year:** 2025
- **one_liner:** AGNTCY's secure, low-latency messaging substrate for agent-to-agent, human-in-the-loop and tool communication, designed for multi-modal exchange and quantum-safe security.
- **spec_url:** https://docs.agntcy.org/
- **snippet:**

```
SLIM carries agent ↔ agent / human / tool messages with low latency and quantum-safe security.
```
- **abbreviation:** SLIM
- **also_known_as:** Secure Low-latency Interactive Messaging
- **canonical_spec_url:** https://docs.agntcy.org/messaging/slim-core/
- **entity_uri:** https://github.com/agntcy
- **taxonomy_layer:** interop
- **sub_layer:** agent-messaging-substrate
- **protocol_type:** transport
- **central_problem:** Gives multi-agent systems a secure, low-latency messaging substrate for agent-to-agent, human-in-the-loop, and tool communication with multi-modal data and quantum-safe security.
- **maintainer:** AGNTCY project under the Linux Foundation (originated at Cisco / Outshift)
- **governance_body:** Linux Foundation (AGNTCY)
- **license:** Apache-2.0
- **maturity_tag:** emerging
- **current_spec_version:** — (verify-against-primary-at-build)
- **spec_date:** — (verify-against-primary-at-build)
- **launch_date:** 2025
- **last_verified:** 2026-06-15
- **transport:** Low-latency messaging substrate (multi-modal; quantum-safe security by design)
- **core_mechanism:** SLIM (Secure Low-latency Interactive Messaging) handles the communication patterns of AGNTCY: agent-to-agent, human-in-the-loop, and tool exchanges, optimized for low-latency multi-modal data with quantum-safe security designed in. It is the messaging leg of AGNTCY's Internet-of-Agents stack, paired with OASF discovery.
- **discovery_endpoint:** SLIM messaging endpoints (AGNTCY component; implementation-defined)
- **settlement_type:** —
- **adoption_metric:** — (verify-against-primary-at-build)
- **notable_adopters:** {"value":"Cisco / Outshift (originator)","source":"https://www.linuxfoundation.org/press/linux-foundation-welcomes-the-agntcy-project-to-standardize-open-multi-agent-system-infrastructure-and-break-down-ai-agent-silos"}
- **relationships:** {"predicate":"part_of","target":"agntcy","note":"SLIM -part_of-> AGNTCY: SLIM is AGNTCY's secure messaging component (paired with OASF discovery)."}, {"predicate":"competes_with","target":"a2a","note":"SLIM is an agent messaging transport, overlapping with A2A's task/message transport."}
- **ideal_use_case:** The secure, low-latency message bus for a multi-agent system built on AGNTCY, including human-in-the-loop steps.
- **when_to_use:** When you need a purpose-built, low-latency, quantum-safe messaging substrate across agents, humans, and tools within AGNTCY.
- **when_not_to_use:** When A2A's HTTP/JSON-RPC transport or plain REST (ACP) already meets your messaging needs.
- **code_example:** // SLIM messaging (schematic)
// slim.connect(agent.endpoint); slim.send({ to: 'planner', modality: 'text', body: '...' })
- **source:** SLIM as AGNTCY's secure low-latency messaging component (agent/human/tool, multi-modal, quantum-safe): https://docs.agntcy.org/ ; AGNTCY/LF context https://www.linuxfoundation.org/press/linux-foundation-welcomes-the-agntcy-project-to-standardize-open-multi-agent-system-infrastructure-and-break-down-ai-agent-silos . Listed for addition in research §2.
- **agent_readiness_link:** agent-readiness/a2a
- **layer_legacy:** agent