Obsidian-skills json-canvas
Create and edit JSON Canvas files (.canvas) with nodes, edges, groups, and connections. Use when working with .canvas files, creating visual canvases, mind maps, flowcharts, or when the user mentions Canvas files in Obsidian.
git clone https://github.com/kepano/obsidian-skills
T=$(mktemp -d) && git clone --depth=1 https://github.com/kepano/obsidian-skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/json-canvas" ~/.claude/skills/kepano-obsidian-skills-json-canvas && rm -rf "$T"
skills/json-canvas/SKILL.mdJSON Canvas Skill
File Structure
A canvas file (
.canvas) contains two top-level arrays following the JSON Canvas Spec 1.0:
{ "nodes": [], "edges": [] }
(optional): Array of node objectsnodes
(optional): Array of edge objects connecting nodesedges
Common Workflows
1. Create a New Canvas
- Create a
file with the base structure.canvas{"nodes": [], "edges": []} - Generate unique 16-character hex IDs for each node (e.g.,
)"6f0ad84f44ce9c17" - Add nodes with required fields:
,id
,type
,x
,y
,widthheight - Add edges referencing valid node IDs via
andfromNodetoNode - Validate: Parse the JSON to confirm it is valid. Verify all
/fromNode
values exist in the nodes arraytoNode
2. Add a Node to an Existing Canvas
- Read and parse the existing
file.canvas - Generate a unique ID that does not collide with existing node or edge IDs
- Choose position (
,x
) that avoids overlapping existing nodes (leave 50-100px spacing)y - Append the new node object to the
arraynodes - Optionally add edges connecting the new node to existing nodes
- Validate: Confirm all IDs are unique and all edge references resolve to existing nodes
3. Connect Two Nodes
- Identify the source and target node IDs
- Generate a unique edge ID
- Set
andfromNode
to the source and target IDstoNode - Optionally set
/fromSide
(top, right, bottom, left) for anchor pointstoSide - Optionally set
for descriptive text on the edgelabel - Append the edge to the
arrayedges - Validate: Confirm both
andfromNode
reference existing node IDstoNode
4. Edit an Existing Canvas
- Read and parse the
file as JSON.canvas - Locate the target node or edge by
id - Modify the desired attributes (text, position, color, etc.)
- Write the updated JSON back to the file
- Validate: Re-check all ID uniqueness and edge reference integrity after editing
Nodes
Nodes are objects placed on the canvas. Array order determines z-index: first node = bottom layer, last node = top layer.
Generic Node Attributes
| Attribute | Required | Type | Description |
|---|---|---|---|
| Yes | string | Unique 16-char hex identifier |
| Yes | string | , , , or |
| Yes | integer | X position in pixels |
| Yes | integer | Y position in pixels |
| Yes | integer | Width in pixels |
| Yes | integer | Height in pixels |
| No | canvasColor | Preset - or hex (e.g., ) |
Text Nodes
| Attribute | Required | Type | Description |
|---|---|---|---|
| Yes | string | Plain text with Markdown syntax |
{ "id": "6f0ad84f44ce9c17", "type": "text", "x": 0, "y": 0, "width": 400, "height": 200, "text": "# Hello World\n\nThis is **Markdown** content." }
Newline pitfall: Use
\n for line breaks in JSON strings. Do not use the literal \\n -- Obsidian renders that as the characters \ and n.
File Nodes
| Attribute | Required | Type | Description |
|---|---|---|---|
| Yes | string | Path to file within the system |
| No | string | Link to heading or block (starts with ) |
{ "id": "a1b2c3d4e5f67890", "type": "file", "x": 500, "y": 0, "width": 400, "height": 300, "file": "Attachments/diagram.png" }
Link Nodes
| Attribute | Required | Type | Description |
|---|---|---|---|
| Yes | string | External URL |
{ "id": "c3d4e5f678901234", "type": "link", "x": 1000, "y": 0, "width": 400, "height": 200, "url": "https://obsidian.md" }
Group Nodes
Groups are visual containers for organizing other nodes. Position child nodes inside the group's bounds.
| Attribute | Required | Type | Description |
|---|---|---|---|
| No | string | Text label for the group |
| No | string | Path to background image |
| No | string | , , or |
{ "id": "d4e5f6789012345a", "type": "group", "x": -50, "y": -50, "width": 1000, "height": 600, "label": "Project Overview", "color": "4" }
Edges
Edges connect nodes via
fromNode and toNode IDs.
| Attribute | Required | Type | Default | Description |
|---|---|---|---|---|
| Yes | string | - | Unique identifier |
| Yes | string | - | Source node ID |
| No | string | - | , , , or |
| No | string | | or |
| Yes | string | - | Target node ID |
| No | string | - | , , , or |
| No | string | | or |
| No | canvasColor | - | Line color |
| No | string | - | Text label |
{ "id": "0123456789abcdef", "fromNode": "6f0ad84f44ce9c17", "fromSide": "right", "toNode": "a1b2c3d4e5f67890", "toSide": "left", "toEnd": "arrow", "label": "leads to" }
Colors
The
canvasColor type accepts either a hex string or a preset number:
| Preset | Color |
|---|---|
| Red |
| Orange |
| Yellow |
| Green |
| Cyan |
| Purple |
Preset color values are intentionally undefined -- applications use their own brand colors.
ID Generation
Generate 16-character lowercase hexadecimal strings (64-bit random value):
"6f0ad84f44ce9c17" "a3b2c1d0e9f8a7b6"
Layout Guidelines
- Coordinates can be negative (canvas extends infinitely)
increases right,x
increases down; position is the top-left cornery- Space nodes 50-100px apart; leave 20-50px padding inside groups
- Align to grid (multiples of 10 or 20) for cleaner layouts
| 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 |
Validation Checklist
After creating or editing a canvas file, verify:
- All
values are unique across both nodes and edgesid - Every
andfromNode
references an existing node IDtoNode - Required fields are present for each node type (
for text nodes,text
for file nodes,file
for link nodes)url
is one of:type
,text
,file
,linkgroup
/fromSide
values are one of:toSide
,top
,right
,bottomleft
/fromEnd
values are one of:toEnd
,nonearrow- Color presets are
through"1"
or valid hex (e.g.,"6"
)"#FF0000" - JSON is valid and parseable
If validation fails, check for duplicate IDs, dangling edge references, or malformed JSON strings (especially unescaped newlines in text content).
Complete Examples
See references/EXAMPLES.md for full canvas examples including mind maps, project boards, research canvases, and flowcharts.