Wren MCP

Overview & setup

Wren’s MCP server lets an AI assistant write into a user’s Wren notebook. Strokes are drawn by Wren’s own engine, so the result is editable handwriting that syncs to the user’s iPad.

Server details

Wren MCP server details
Endpoint	`https://mcp.wrenapp.ai/mcp`
Transport	Streamable HTTP, `POST` only. `GET` returns 405.
Protocol version	`2025-06-18`
Sessions	Stateless. No session id; every request stands alone.
Auth	OAuth 2.0 authorization code + PKCE. See Authentication.
Capabilities	Tools and resources. No prompts.

Connect a client

You need a Wren account. The client opens a Wren sign-in page the first time it calls a tool that touches notes.

Terminal

claude mcp add --transport http wren https://mcp.wrenapp.ai/mcp

Claude Code: run /mcp and authenticate wren.
Cursor: sign in when Cursor prompts you.
Codex: run codex mcp login wren.
Claude (claude.ai and Desktop): Settings, then Connectors, then Add custom connector. Enter https://mcp.wrenapp.ai/mcp, save, and choose Connect.

Any other client that supports remote MCP servers over Streamable HTTP with OAuth can use the same URL.

Verify the server is reachable

Listing tools needs no sign-in, so it is the quickest connectivity check:

Terminal

curl -s https://mcp.wrenapp.ai/mcp \
  -H 'content-type: application/json' \
  -H 'accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

You should get all 10 tools back. Continue with the tool reference or run the JSON-RPC examples.

Try it from an assistant

Once connected, ask your assistant something like:

“Handwrite a short paragraph about why practice matters in math, in Wren.”
“Graph y = x^2 - 4 in a new Wren note called Quadratics.”
“Add a page to my Quadratics note with the quadratic formula.”
“Make a flowchart of the scientific method in Wren.”

What Wren will and won’t change

The user’s own handwriting is never modified. edit_page only works on pages Wren wrote.
Wren draws exactly the content you send; it does not invent content.
Tools that read or change notes need an access token with the matching scope. Discovery and get_drawing_guide do not.

See the privacy policy for how data is handled, or contact support.