An MCP server lets an AI assistant draw on a whiteboard instead of describing a picture in text. The servers below differ in three ways that matter: what you have to sign in with, how many tool calls you get, and where the drawing ends up (in the chat, in your team's workspace, or on a board other people can open). Every fact here comes from the maker's own docs, checked 23 October 2026. We make cnvs.app, so read our row with that in mind.
| Server | Sign-in | Published limits | Where the drawing lives |
|---|---|---|---|
| Miro MCP server | OAuth 2.1 with your Miro account; on Enterprise an admin must enable it first | Works on every plan, Free included. Daily tool calls: Free 100, Starter 500, Business 2,000, Enterprise 10,000 (reset 00:00 UTC) | Your Miro boards |
| Figma MCP server (Figma and FigJam) | Figma sign-in; only clients in Figma's MCP catalog can connect | Read tool calls: up to 20 a month on Starter, or with View or Collab seats; Full or Dev seats on Professional up to 200 a day. Writing outside your drafts needs a Full seat; writing is free during the beta and will become a usage-based paid feature | Your Figma and FigJam files (generate_diagram turns a description or Mermaid into a FigJam diagram) |
| Excalidraw MCP app (open source) | None documented | None published | Streamed into the chat in clients that support MCP Apps, with fullscreen editing |
| Excalidraw+ MCP | Excalidraw+ workspace and an API key (personal, if your admin enables them, or workspace) sent as a bearer token | Public beta; tools follow the key's API permissions | Your Excalidraw+ workspace |
| tldraw MCP app | None documented for the MCP app (in Claude: Settings › Connectors › Browse connectors; other clients add it to their MCP settings); the ChatGPT and Codex plugin signs in to a free tldraw.com account | None published | A tldraw canvas inside the chat that you and the agent both edit; with the ChatGPT/Codex plugin, real tldraw.com files you can share |
| draw.io MCP app | None documented (hosted, no installation) | None published | Rendered inline in the chat; "Open in draw.io" to edit. A separate npm tool server opens diagrams in the draw.io editor |
| cnvs.app MCP endpoint | None. The board ID is the access key; optional PIN lock per board | Free; machine-readable quotas at /quotas.json | A shared board at a URL: people in a browser and AI agents edit it at the same time; every tool has a REST mirror |
Sources, all checked 23 October 2026: Miro MCP server docs and usage and daily limits; Figma MCP server FAQs and tools and prompts; Excalidraw excalidraw-mcp README and Excalidraw+ MCP docs and key types; tldraw MCP app post and ChatGPT and Codex plugin post (29 September 2026); draw.io drawio-mcp README; cnvs.app MCP docs. "None documented" means the maker's page shows no sign-in step, not that we tested every client. Plans and limits change; check the linked page before you rely on a number.
The board has to live where your team already works, with its permissions, templates, voting and design files. Whoever connects the MCP server signs in with their account, and tool calls come out of a daily or monthly allowance tied to the plan.
You want a diagram inside the conversation right now: a sketch, a flowchart, an architecture diagram with real cloud icons (draw.io's shape search). You edit it in the chat or open it in the app afterwards.
The agent should work on a board other people can open from a link while it works: a client, a candidate, a class. Nobody signs up, edits from people and agents sync live, and agents can subscribe to board changes instead of polling.
Claude Code:
claude mcp add --transport http cnvs https://cnvs.app/mcpAny other MCP client: add https://cnvs.app/mcp as a remote (Streamable HTTP) server. Tools include open_board, get_board, get_preview, add_text (Markdown, Mermaid, sticky notes), draw_stroke, move and erase. Full list and client configs: MCP docs · AI whiteboard via MCP · REST API.
Honest limits: no shape libraries, no voting or facilitator tools, no SSO or per-user permissions (anyone with the board ID can edit unless it is PIN-locked), and boards are deleted after up to 30 days of inactivity.
Besides the makers' own servers there are community MCP servers that run on your computer and drive a local canvas, for example mcp_excalidraw for a live Excalidraw canvas. By default they run on one machine for Claude Code or Cursor; letting other people join means hosting the server yourself.
An MCP (Model Context Protocol) server that lets an AI assistant such as Claude, ChatGPT or Cursor draw on a whiteboard or diagram tool: add shapes, notes, connectors or whole diagrams, and read what is already there.
Excalidraw's open-source MCP app, draw.io's hosted MCP app, tldraw's MCP app for Claude and Cursor, and cnvs.app's MCP endpoint are documented without a sign-in step. Miro and Figma need you to sign in with your account, tldraw's ChatGPT and Codex plugin needs a free tldraw.com account, and Excalidraw+ needs an Excalidraw+ API key (personal, if your admin enables them, or workspace).
Miro lists daily MCP tool calls per plan: Free 100, Starter 500, Business 2,000, Enterprise 10,000, reset at 00:00 UTC. Figma lists up to 20 read tool calls a month on Starter and for View or Collab seats, and up to 200 a day for Full or Dev seats on Professional; writing outside your drafts needs a Full seat. Both checked 23 October 2026.
Excalidraw's and draw.io's hosted MCP apps draw the diagram inside the chat, and you open or export it from there. cnvs.app's tools write to a shared board at a URL, so people in a browser and one or more AI agents edit the same board at the same time, with a REST mirror of every tool.
No shape libraries like draw.io's, no voting or facilitation tools like Miro's or FigJam's, no Figma design-file integration, and no SSO or per-user permissions: whoever knows the board ID can edit unless the board is PIN-locked. Boards are deleted after up to 30 days of inactivity.