[ PROMPT_NODE_25639 ]
Json Canvas
[ SKILL_DOCUMENTATION ]
# JSON Canvas Skill
This skill enables Claude Code to create and edit valid JSON Canvas files (`.canvas`) used in Obsidian and other applications.
## Overview
JSON Canvas is an open file format for infinite canvas data. Canvas files use the `.canvas` extension and contain valid JSON following the [JSON Canvas Spec 1.0](https://jsoncanvas.org/spec/1.0/).
## File Structure
A canvas file contains two top-level arrays:
```json
{
"nodes": [],
"edges": []
}
```
- `nodes` (optional): Array of node objects
- `edges` (optional): Array of edge objects connecting nodes
## Nodes
Nodes are objects placed on the canvas. There are four node types:
- `text` - Text content with Markdown
- `file` - Reference to files/attachments
- `link` - External URL
- `group` - Visual container for other nodes
### Z-Index Ordering
Nodes are ordered by z-index in the array:
- First node = bottom layer (displayed below others)
- Last node = top layer (displayed above others)
### Generic Node Attributes
All nodes share these attributes:
| Attribute | Required | Type | Description |
|-----------|----------|------|-------------|
| `id` | Yes | string | Unique identifier for the node |
| `type` | Yes | string | Node type: `text`, `file`, `link`, or `group` |
| `x` | Yes | integer | X position in pixels |
| `y` | Yes | integer | Y position in pixels |
| `width` | Yes | integer | Width in pixels |
| `height` | Yes | integer | Height in pixels |
| `color` | No | canvasColor | Node color (see Color section) |
### Text Nodes
Text nodes contain Markdown content.
```json
{
"id": "6f0ad84f44ce9c17",
"type": "text",
"x": 0,
"y": 0,
"width": 400,
"height": 200,
"text": "# Hello WorldnnThis is **Markdown** content."
}
```
| Attribute | Required | Type | Description |
|-----------|----------|------|-------------|
| `text` | Yes | string | Plain text with Markdown syntax |
### File Nodes
File nodes reference files or attachments (images, videos, PDFs, notes, etc.).
```json
{
"id": "a1b2c3d4e5f67890",
"type": "file",
"x": 500,
"y": 0,
"width": 400,
"height": 300,
"file": "Attachments/diagram.png"
}
```
```json
{
"id": "b2c3d4e5f6789012",
"type": "file",
"x": 500,
"y": 400,
"width": 400,
"height": 300,
"file": "Notes/Project Overview.md",
"subpath": "#Implementation"
}
```
| Attribute | Required | Type | Description |
|-----------|----------|------|-------------|
| `file` | Yes | string | Path to file within the system |
| `subpath` | No | string | Link to heading or block (starts with `#`) |
### Link Nodes
Link nodes display external URLs.
```json
{
"id": "c3d4e5f678901234",
"type": "link",
"x": 1000,
"y": 0,
"width": 400,
"height": 200,
"url": "https://obsidian.md"
}
```
| Attribute | Required | Type | Description |
|-----------|----------|------|-------------|
| `url` | Yes | string | External URL |
### Group Nodes
Group nodes are visual containers for organizing other nodes.
```json
{
"id": "d4e5f6789012345a",
"type": "group",
"x": -50,
"y": -50,
"width": 1000,
"height": 600,
"label": "Project Overview",
"color": "4"
}
```
```json
{
"id": "e5f67890123456ab",
"type": "group",
"x": 0,
"y": 700,
"width": 800,
"height": 500,
"label": "Resources",
"background": "Attachments/background.png",
"backgroundStyle": "cover"
}
```
| Attribute | Required | Type | Description |
|-----------|----------|------|-------------|
| `label` | No | string | Text label for the group |
| `background` | No | string | Path to background image |
| `backgroundStyle` | No | string | Background rendering style |
#### Background Styles
| Value | Description |
|-------|-------------|
| `cover` | Fills entire width and height of node |
| `ratio` | Maintains aspect ratio of background image |
| `repeat` | Repeats image as pattern in both directions |
## Edges
Edges are lines connecting nodes.
```json
{
"id": "f67890123456789a",
"fromNode": "6f0ad84f44ce9c17",
"toNode": "a1b2c3d4e5f67890"
}
```
```json
{
"id": "0123456789abcdef",
"fromNode": "6f0ad84f44ce9c17",
"fromSide": "right",
"fromEnd": "none",
"toNode": "b2c3d4e5f6789012",
"toSide": "left",
"toEnd": "arrow",
"color": "1",
"label": "leads to"
}
```
| Attribute | Required | Type | Default | Description |
|-----------|----------|------|---------|-------------|
| `id` | Yes | string | - | Unique identifier for the edge |
| `fromNode` | Yes | string | - | Node ID where connection starts |
| `fromSide` | No | string | - | Side where edge starts |
| `fromEnd` | No | string | `none` | Shape at edge start |
| `toNode` | Yes | string | - | Node ID where connection ends |
| `toSide` | No | string | - | Side where edge ends |
| `toEnd` | No | string | `arrow` | Shape at edge end |
| `color` | No | canvasColor | - | Line color |
| `label` | No | string | - | Text label for the edge |
### Side Values
| Value | Description |
|-------|-------------|
| `top` | Top edge of node |
| `right` | Right edge of node |
| `bottom` | Bottom edge of node |
| `left` | Left edge of node |
### End Shapes
| Value | Description |
|-------|-------------|
| `none` | No endpoint shape |
| `arrow` | Arrow endpoint |
## Colors
The `canvasColor` type can be specified in two ways:
### Hex Colors
```json
{
"color": "#FF0000"
}
```
### Preset Colors
```json
{
"color": "1"
}
```
| Preset | Color |
|--------|-------|
| `"1"` | Red |
| `"2"` | Orange |
| `"3"` | Yellow |
| `"4"` | Green |
| `"5"` | Cyan |
| `"6"` | Purple |
Note: Specific color values for presets are intentionally undefined, allowing applications to use their own brand colors.
## Complete Examples
### Simple Canvas with Text and Connections
```json
{
"nodes": [
{
"id": "8a9b0c1d2e3f4a5b",
"type": "text",
"x": 0,
"y": 0,
"width": 300,
"height": 150,
"text": "# Main IdeannThis is the central concept."
},
{
"id": "1a2b3c4d5e6f7a8b",
"type": "text",
"x": 400,
"y": -100,
"width": 250,
"height": 100,
"text": "## Supporting Point AnnDetails here."
},
{
"id": "2b3c4d5e6f7a8b9c",
"type": "text",
"x": 400,
"y": 100,
"width": 250,
"height": 100,
"text": "## Supporting Point BnnMore details."
}
],
"edges": [
{
"id": "3c4d5e6f7a8b9c0d",
"fromNode": "8a9b0c1d2e3f4a5b",
"fromSide": "right",
"toNode": "1a2b3c4d5e6f7a8b",
"toSide": "left"
},
{
"id": "4d5e6f7a8b9c0d1e",
"fromNode": "8a9b0c1d2e3f4a5b",
"fromSide": "right",
"toNode": "2b3c4d5e6f7a8b9c",
"toSide": "left"
}
]
}
```
### Project Board with Groups
```json
{
"nodes": [
{
"id": "5e6f7a8b9c0d1e2f",
"type": "group",
"x": 0,
"y": 0,
"width": 300,
"height": 500,
"label": "To Do",
"color": "1"
},
{
"id": "6f7a8b9c0d1e2f3a",
"type": "group",
"x": 350,
"y": 0,
"width": 300,
"height": 500,
"label": "In Progress",
"color": "3"
},
{
"id": "7a8b9c0d1e2f3a4b",
"type": "group",
"x": 700,
"y": 0,
"width": 300,
"height": 500,
"label": "Done",
"color": "4"
},
{
"id": "8b9c0d1e2f3a4b5c",
"type": "text",
"x": 20,
"y": 50,
"width": 260,
"height": 80,
"text": "## Task 1nnImplement feature X"
},
{
"id": "9c0d1e2f3a4b5c6d",
"type": "text",
"x": 370,
"y": 50,
"width": 260,
"height": 80,
"text": "## Task 2nnReview PR #123",
"color": "2"
},
{
"id": "0d1e2f3a4b5c6d7e",
"type": "text",
"x": 720,
"y": 50,
"width": 260,
"height": 80,
"text": "## Task 3nn~~Setup CI/CD~~"
}
],
"edges": []
}
```
### Research Canvas with Files and Links
```json
{
"nodes": [
{
"id": "1e2f3a4b5c6d7e8f",
"type": "text",
"x": 300,
"y": 200,
"width": 400,
"height": 200,
"text": "# Research Topicnn## Key Questionsnn- How does X affect Y?n- What are the implications?",
"color": "5"
},
{
"id": "2f3a4b5c6d7e8f9a",
"type": "file",
"x": 0,
"y": 0,
"width": 250,
"height": 150,
"file": "Literature/Paper A.pdf"
},
{
"id": "3a4b5c6d7e8f9a0b",
"type": "file",
"x": 0,
"y": 200,
"width": 250,
"height": 150,
"file": "Notes/Meeting Notes.md",
"subpath": "#Key Insights"
},
{
"id": "4b5c6d7e8f9a0b1c",
"type": "link",
"x": 0,
"y": 400,
"width": 250,
"height": 100,
"url": "https://example.com/research"
},
{
"id": "5c6d7e8f9a0b1c2d",
"type": "file",
"x": 750,
"y": 150,
"width": 300,
"height": 250,
"file": "Attachments/diagram.png"
}
],
"edges": [
{
"id": "6d7e8f9a0b1c2d3e",
"fromNode": "2f3a4b5c6d7e8f9a",
"fromSide": "right",
"toNode": "1e2f3a4b5c6d7e8f",
"toSide": "left",
"label": "supports"
},
{
"id": "7e8f9a0b1c2d3e4f",
"fromNode": "3a4b5c6d7e8f9a0b",
"fromSide": "right",
"toNode": "1e2f3a4b5c6d7e8f",
"toSide": "left",
"label": "informs"
},
{
"id": "8f9a0b1c2d3e4f5a",
"fromNode": "4b5c6d7e8f9a0b1c",
"fromSide": "right",
"toNode": "1e2f3a4b5c6d7e8f",
"toSide": "left",
"toEnd": "arrow",
"color": "6"
},
{
"id": "9a0b1c2d3e4f5a6b",
"fromNode": "1e2f3a4b5c6d7e8f",
"fromSide": "right",
"toNode": "5c6d7e8f9a0b1c2d",
"toSide": "left",
"label": "visualized by"
}
]
}
```
### Flowchart
```json
{
"nodes": [
{
"id": "a0b1c2d3e4f5a6b7",
"type": "text",
"x": 200,
"y": 0,
"width": 150,
"height": 60,
"text": "**Start**",
"color": "4"
},
{
"id": "b1c2d3e4f5a6b7c8",
"type": "text",
"x": 200,
"y": 100,
"width": 150,
"height": 60,
"text": "Step 1:nGather data"
},
{
"id": "c2d3e4f5a6b7c8d9",
"type": "text",
"x": 200,
"y": 200,
"width": 150,
"height": 80,
"text": "**Decision**nnIs data valid?",
"color": "3"
},
{
"id": "d3e4f5a6b7c8d9e0",
"type": "text",
"x": 400,
"y": 200,
"width": 150,
"height": 60,
"text": "Process data"
},
{
"id": "e4f5a6b7c8d9e0f1",
"type": "text",
"x": 0,
"y": 200,
"width": 150,
"height": 60,
"text": "Request new data",
"color": "1"
},
{
"id": "f5a6b7c8d9e0f1a2",
"type": "text",
"x": 400,
"y": 320,
"width": 150,
"height": 60,
"text": "**End**",
"color": "4"
}
],
"edges": [
{
"id": "a6b7c8d9e0f1a2b3",
"fromNode": "a0b1c2d3e4f5a6b7",
"fromSide": "bottom",
"toNode": "b1c2d3e4f5a6b7c8",
"toSide": "top"
},
{
"id": "b7c8d9e0f1a2b3c4",
"fromNode": "b1c2d3e4f5a6b7c8",
"fromSide": "bottom",
"toNode": "c2d3e4f5a6b7c8d9",
"toSide": "top"
},
{
"id": "c8d9e0f1a2b3c4d5",
"fromNode": "c2d3e4f5a6b7c8d9",
"fromSide": "right",
"toNode": "d3e4f5a6b7c8d9e0",
"toSide": "left",
"label": "Yes",
"color": "4"
},
{
"id": "d9e0f1a2b3c4d5e6",
"fromNode": "c2d3e4f5a6b7c8d9",
"fromSide": "left",
"toNode": "e4f5a6b7c8d9e0f1",
"toSide": "right",
"label": "No",
"color": "1"
},
{
"id": "e0f1a2b3c4d5e6f7",
"fromNode": "e4f5a6b7c8d9e0f1",
"fromSide": "top",
"fromEnd": "none",
"toNode": "b1c2d3e4f5a6b7c8",
"toSide": "left",
"toEnd": "arrow"
},
{
"id": "f1a2b3c4d5e6f7a8",
"fromNode": "d3e4f5a6b7c8d9e0",
"fromSide": "bottom",
"toNode": "f5a6b7c8d9e0f1a2",
"toSide": "top"
}
]
}
```
## ID Generation
Node and edge IDs must be unique strings. Obsidian generates 16-character hexadecimal IDs:
```json
"id": "6f0ad84f44ce9c17"
"id": "a3b2c1d0e9f8g7h6"
"id": "1234567890abcdef"
```
This format is a 16-character lowercase hex string (64-bit random value).
## Layout Guidelines
### Positioning
- Coordinates can be negative (canvas extends infinitely)
- `x` increases to the right
- `y` increases downward
- Position refers to top-left corner of node
### Recommended Sizes
| Node Type | Suggested Width | Suggested Height |
|-----------|-----------------|------------------|
| Small text | 200-300 | 80-150 |
| Medium text | 300-450 | 150-300 |
| Large text | 400-600 | 300-500 |
| File preview | 300-500 | 200-400 |
| Link preview | 250-400 | 100-200 |
| Group | Varies | Varies |
### Spacing
- Leave 20-50px padding inside groups
- Space nodes 50-100px apart for readability
- Align nodes to grid (multiples of 10 or 20) for cleaner layouts
## Validation Rules
1. All `id` values must be unique across nodes and edges
2. `fromNode` and `toNode` must reference existing node IDs
3. Required fields must be present for each node type
4. `type` must be one of: `text`, `file`, `link`, `group`
5. `backgroundStyle` must be one of: `cover`, `ratio`, `repeat`
6. `fromSide`, `toSide` must be one of: `top`, `right`, `bottom`, `left`
7. `fromEnd`, `toEnd` must be one of: `none`, `arrow`
8. Color presets must be `"1"` through `"6"` or valid hex color
## References
- [JSON Canvas Spec 1.0](https://jsoncanvas.org/spec/1.0/)
- [JSON Canvas GitHub](https://github.com/obsidianmd/jsoncanvas)
Source: claude-code-templates (MIT). See About Us for full credits.