open_canvas

Show a board inline in clients with MCP Apps and get its web link. Without a canvasId it creates a new board and shows it.

Plan	Quota	Changes data	Hints
All	Without `canvasId`: counts toward the canvas limit	Only when it creates a board

open_canvas is linked to the MCP Apps resource ui://banana/canvas. Clients that support MCP Apps (Claude.ai, Claude Desktop) render the board in the chat. Every client gets the web link in the text.

Inputs

Name	Type	Required	Limits	What it does
`canvasId`	string	No	1 to 100 characters	The board to show. Leave out to create a new one
`title`	string	No	1 to 80 characters	Title for a new board
`brief`	string	No	1 to 500 characters	Brief for a new board
`taste`	string[]	No	1 to 5 words	Style words for searches on this board

Example call

{ "name": "open_canvas", "arguments": { "canvasId": "c3f1a0d2-6b1e-4d8a-9f4b-0a1b2c3d4e5f" } }

Example output

Opened canvas "Coffee launch page" (id c3f1a0d2-6b1e-4d8a-9f4b-0a1b2c3d4e5f).
Web link: https://gobanana.fun/c/c3f1a0d2-6b1e-4d8a-9f4b-0a1b2c3d4e5f
It has 31 items and 9 results in its tray.

structuredContent.canvas is small on purpose (id, title, webUrl, brief, items, sections, tray counts) because some hosts show it to the model. The full board goes to the view only, in the result’s _meta.

The inline view

Pan, zoom, move, edit notes, use keyboard shortcuts. Changes save to the same board as the web.
It refreshes on its own while visible: about every 4 seconds with focus, 15 seconds without, never while hidden.
Upload and Share are web only; uploads show as link cards inline.

Messages

Message	Fix
“canvasId must be an id from open_canvas.”	Use an id from `get_canvas`
“That canvas was not found…”	Wrong id or another account
“You have used your 3 free canvases…”	Only when creating