# Agent Client Protocol

> Apache-2.0 LSP-for-agents: one protocol so any editor can talk to any coding agent

**Category:** AI Agents  
**Pricing:** open-source  
**URL:** https://agentclientprotocol.com  
**GitHub:** https://github.com/agentclientprotocol/agent-client-protocol  
**Added:** 2026-10-12

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## The Hook

ACP standardizes how code editors and coding agents talk — JSON-RPC locally over stdio today, with remote HTTP/WebSocket work in progress — so you stop writing a custom bridge for every agent/editor pair.

## What's Good

Apache-2.0 (agentclientprotocol/agent-client-protocol), schema release schema-v1.25.0 (2026-10-09); stable wire protocol version is 1 via `initialize`. Schema crate and versioned JSON Schema artifacts for SDK generators; higher-level Rust runtime crate for implementers. Reuses MCP-style JSON where it fits, plus agent UX types such as diffs. Markdown is the default user-facing text format. Registry of ACP agents and adapters lives under the same org. ★~4.4k.

## The Catch

A protocol, not an app — both the editor and the agent must implement ACP before you feel the benefit. Full remote/cloud agent support is still in progress. Schema artifact versions can move without changing wire compatibility, which matters if you generate SDKs from the JSON Schema. Vs MCP (tool/server protocol for model context): ACP is the editor↔agent session protocol; they solve different layers and often ship together.

## Verdict

The interoperability bet for coding agents — adopt it when you build an editor or an agent, not when you just want a chat UI.