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Connect Codex or Claude to OpenChatCut with MCP

Use the local Streamable HTTP MCP endpoint so external agents can read OpenChatCut projects, edit the timeline, and stay undoable.

Jul 21, 2026OpenChatCutOpenChatCut
Connect Codex or Claude to OpenChatCut with MCP

OpenChatCut is more than an in-app chat agent. It also exposes project capabilities through the Model Context Protocol (MCP) so Codex, Claude Code, or other compatible clients can drive the same multitrack project.

Why MCP

The chat panel is great for fast iteration. MCP is great when you want to:

  • Edit from an Agent CLI or IDE you already use
  • Capture editing steps in a repeatable session
  • Let multiple agents share one project model instead of private one-off APIs

Agents work with structured project objects (media, tracks, selection, captions)—not screen coordinates.

Local endpoint

The dev server and desktop-embedded server expose Streamable HTTP MCP by default:

http://localhost:5199/api/external-mcp/mcp

Start OpenChatCut first (npm run dev from source or the desktop app) and confirm the local port is reachable. Auth and project lifecycle follow the current server implementation; secrets must stay server-side.

Recommended flow

  1. Open or create a project and import media.
  2. Register the MCP server in your agent client.
  3. Have the agent read project state first: tracks, clips, transcript, selection.
  4. Give a concrete goal, e.g. “Remove pauses longer than 0.5s, add captions, duck BGM under speech.”
  5. Preview in the editor, undo if needed, or continue the conversation.

Built-in agent vs external MCP

  • Entry — built-in agent lives in the app chat; external MCP agents run in Codex / Claude Code and similar clients.
  • Mutation path — both use the same editor commands.
  • Secrets — built-in uses local app config; external clients keep their own keys.
  • Best for — built-in for talk-while-previewing; MCP for deeper IDE / CLI workflows.

Neither path should bypass the editor command boundary—that is what keeps validation, proposals, and undo consistent.

FAQ

Port is not 5199?
Use whatever host/port your current dev or desktop server logs. Check the terminal or app settings.

Empty tool list?
Confirm the MCP route is enabled, a project is open, and the client uses Streamable HTTP (not a legacy transport).

Can I expose it remotely?
It is local-first by default. Remote exposure needs your own network isolation and auth. Do not publish an unhardened MCP port to the public internet.

Next steps