ACP (Agent Client Protocol) Gains Traction as MCP's Runtime Complement
The Agent Client Protocol (ACP) is establishing independent adoption at an accelerating rate. Zed Industries has published codex-acp — an ACP adapter wrapping the OpenAI Codex CLI for Zed's native ACP-compatible editor — with support for @-mentions, images, tool calls with permission prompts, edit review, TODO lists, and slash commands (/review, /review-branch, /compact). Separately, DeepChat (a cross-platform desktop agent app) treats ACP agents as first-class "models" in its workspace UI, with full session management. The positioning is explicit: MCP = tools and resources, ACP = agent runtime and agent-to-agent coordination.
Why It Matters
If ACP consolidates as MCP's complement, builders will need to support both protocols to participate in the full agentic ecosystem. The good news: ACP is designed to wrap existing agents (Codex CLI, OpenCode, etc.) rather than requiring new implementations. Organizations building agent orchestration infrastructure should track this before it becomes a compatibility requirement.