> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kiwifs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Canvas files

> JSON Canvas files for spatial diagrams — nodes, edges, interactive Flow rendering, and graph-assisted layout.

Canvas files are JSON documents with a **`.canvas.json`** suffix. They store `nodes` and `edges` for infinite-canvas layouts in the web UI and for agents via API or MCP.

## File format

Each canvas is JSON with top-level `nodes` and `edges` arrays. Node and edge objects carry `id`, `type`, optional coordinates (`x`, `y`), and a `data` map for extensibility.

Common node types include file references, text labels, link arrows, and grouped regions.

## Web UI

Click **Canvas** in the toolbar to open the canvas hub. You can create, rename, and switch between canvases stored under `canvases/`. The interactive **Flow** renderer lets you drag nodes, pan and zoom, and edit the diagram visually. Changes persist to the underlying `.canvas.json` file.

## Graph-assisted layout

`POST /api/kiwi/canvas/generate` builds a new canvas from the **wiki-link graph** using layout modes such as `hierarchical`, `radial`, `force`, or `circular`. Restrict to a folder prefix so only part of the graph is laid out.

For canvases that already exist, `POST /api/kiwi/canvas/auto-layout?path=...` repositions nodes using Graphviz engines (`dot`, `neato`, `fdp`, `circo`).

## Incremental edits

Agents can apply batched operations with `PATCH /api/kiwi/canvas` instead of rewriting the full JSON document. See the [Canvas REST API](/api/canvas) for supported `op` values.

## Related documentation

<CardGroup cols={2}>
  <Card title="Canvas REST API" icon="diagram-project" href="/api/canvas">
    List, read, write, patch, query, and auto-layout.
  </Card>

  <Card title="Whiteboard" icon="pen" href="/concepts/whiteboard">
    Excalidraw diagrams in markdown files.
  </Card>

  <Card title="MCP" icon="plug" href="/concepts/mcp">
    `kiwi_canvas_list`, `kiwi_canvas_read`, `kiwi_canvas_write`.
  </Card>

  <Card title="Web UI" icon="window" href="/guides/web-ui">
    Toolbar views including Canvas and Whiteboard.
  </Card>
</CardGroup>