One of the best things to come out of Visual Studio Code is the Language Server Protocol (LSP). It’s the magic glue that decoupled and standardized how language tools worked with editors and it’s what enabled VSCode to pick up support for so many languages so quickly after its release. Now, LSP is a core feature of all the major editors, and keeps the door open for new editors to come to market.

Following this same spirit, the team at Zed is introducing the Agent Client Protocol, and it promises to bring the same benefits to using AI agents in the development environment of your choice. Like LSP, it‘s based on JSON-RPC and supports streaming responses. In Zed’s blog post introducing ACP, Nathan Sobo writes:

Any agent that speaks ACP can plug into a powerful UI, where the user can follow the agent around the codebase as it works, control its access to tools and MCP servers, and review all of its changes in a multi-buffer with full syntax highlighting and language server support.

The first agent besides Zed’s own in-process agent to support ACP is Google’s Gemini CLI. I’m really rooting for this to take off and for tools like Claude Code (still my favorite agent) and OpenAI’s Codex to adopt this standard. The potential for a unified ecosystem of AI coding assistants that support all sorts of editing environments is exciting.