Rook MCP
BETARook 1.3.0 adds support for the Model Context Protocol (MCP), the open protocol AI tools use to talk to programs and data sources. Claude Code, Claude Desktop, Codex, Cursor, and Gemini CLI can save notes to Rook over MCP. Saves appear in Rook immediately.
Useful when you'd otherwise be copy-pasting AI output by hand: a code snippet from a chat, a debugging session summary, action items from a long thread, or the text to prompt the next AI session. Each connected AI saves to Rook.
Configuration
This section walks through setting up Rook MCP with 5 local clients: Claude Code, Codex, Gemini CLI, Cursor, and Claude Desktop.
Add the Rook MCP server to Claude Code with either flag, user-scoped or local-scoped:
claude mcp add rook --scope user -- /Applications/Rook.app/Contents/Helpers/rook-mcp.app/Contents/MacOS/rook-mcpUser scope sets the Rook MCP server in every Claude Code session, regardless of directory.
claude mcp add rook --scope local -- /Applications/Rook.app/Contents/Helpers/rook-mcp.app/Contents/MacOS/rook-mcpLocal scope sets it for the current repo only.
Then, in a new Claude Code session:
save "hello from claude code" to RookYou'll see a “Saved to Rook inbox” confirmation, and a Claude Inbox appears in Rook with the note inside.
Type /mcp inside a Claude Code session to see configured servers.
How it works
Rook 1.3.0 includes the MCP helper, a separate binary installed alongside Rook. When an AI tool connects to Rook, it launches the helper as a child process and communicates with it over stdio. The helper writes saves to a shared inbox folder, an app group container that macOS lets both the helper and Rook access. Rook reads from that folder.
The helper exposes one tool: append a note. An AI tool connected through MCP can add new notes, but cannot read, modify, or remove existing ones.
The helper runs inside macOS's app sandbox. Its entitlements allow two operations: receiving messages from the AI tool that spawned it, and appending to Rook's shared inbox.
The AI tool and helper communicate over local IPC (inter-process communication) only. The helper has no network access and exits when its parent AI tool quits.
Tools
rook-mcp implements MCP protocol 2024-11-05 over stdio. The server exposes one tool.
append_to_inbox
Appends text to the calling client's Rook inbox.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
content | string | yes | The text to save, up to 100,000 characters. |
title | string | no | Short heading shown above the content. Up to 200 characters. |
Returns
A confirmation string. Without a title: Saved to Rook inbox 2026-05-12. With a title: Saved to Rook inbox 2026-05-12 under "my title".
Errors
| Code | Name | Description |
|---|---|---|
| -32002 | rate_limited | More than 100 saves in 60 seconds. Each client process has its own budget. |
| -32003 | paused | MCP is paused in Rook (Settings → MCP → Resume). |
| -32004 | input_invalid | Content is empty, exceeds 100,000 characters, or title is empty after sanitization. |
Common questions
Will my AI see existing Rook notes?
No. The helper exposes no read or list operations. A connected AI can add notes but cannot see existing ones.
Does Rook MCP send data off-device?
No. Communication is stdio only, and the helper's sandbox blocks network access. Saves are written to a local folder that Rook reads from.
Where do saves go?
Each AI gets its own collection in Rook: Claude Inbox, Codex Inbox, Cursor Inbox, Gemini Inbox. Saves from the same client within a day are grouped into a single note.
How can it be turned off?
Settings → MCP has a master toggle. The Pause toggle blocks new saves without removing the client-side configuration.
How do I remove the integration entirely?
Run the matching remove command for each client:
- Claude Code:
claude mcp remove rook - Codex:
codex mcp remove rook - Gemini CLI:
gemini mcp remove rook - Cursor: remove
rookfrom the User MCP Servers list in Settings → Tools & MCPs - Claude Desktop: remove the
rookblock from Settings → Developer → Edit Config
Are there limits?
Up to 100 saves per minute per session, and up to 100,000 characters per save.
What if Rook isn't running when an AI tries to save?
The helper writes the save to disk regardless. Rook picks it up the next time it reads the inbox.
How can I see what's been saved?
Click the MCP indicator in Rook's toolbar. The activity log shows every save attempt with the client name, content size, status, and time.