JSON Canvas

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.

When to Use This Skill

• Creating or editing .canvas files in Obsidian
• Building visual mind maps or flowcharts
• Creating project boards or planning documents
• Organizing notes visually with connections
• Building diagrams with linked content

File Structure

A canvas file contains two top-level arrays:

{
  "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

First node = bottom layer (displayed below others) Last node = top layer (displayed above others)

Generic Node 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.

{
  "id": "text1",
  "type": "text",
  "x": 0,
  "y": 0,
  "width": 300,
  "height": 150,
  "text": "# Heading\n\nThis is **markdown** content."
}

File Nodes

File nodes reference files or attachments (images, videos, PDFs, notes, etc.)

Attribute	Required	Type	Description
file	Yes	string	Path to file within the system
subpath	No	string	Link to heading or block (starts with #)

{
  "id": "file1",
  "type": "file",
  "x": 350,
  "y": 0,
  "width": 400,
  "height": 300,
  "file": "Notes/My Note.md",
  "subpath": "#Heading"
}

Link Nodes

Link nodes display external URLs.

{
  "id": "link1",
  "type": "link",
  "x": 0,
  "y": 200,
  "width": 300,
  "height": 150,
  "url": "https://example.com"
}

Group Nodes

Group nodes are visual containers for organizing other nodes.

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

{
  "id": "group1",
  "type": "group",
  "x": -50,
  "y": -50,
  "width": 800,
  "height": 500,
  "label": "Project Ideas",
  "color": "4"
}

Edges

Edges are lines connecting nodes.

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

{
  "id": "edge1",
  "fromNode": "text1",
  "fromSide": "right",
  "toNode": "file1",
  "toSide": "left",
  "toEnd": "arrow",
  "label": "references"
}

Colors

The canvasColor type supports both hex colors and preset options.

Hex Colors

{
  "color": "#FF0000"
}

Preset Colors

Preset	Color
"1"	Red
"2"	Orange
"3"	Yellow
"4"	Green
"5"	Cyan
"6"	Purple

Specific color values for presets are intentionally undefined, allowing applications to use their own brand colors.

Complete Examples

Simple Canvas with Text and Connections

{
  "nodes": [
    {
      "id": "idea1",
      "type": "text",
      "x": 0,
      "y": 0,
      "width": 250,
      "height": 100,
      "text": "# Main Idea\n\nCore concept goes here"
    },
    {
      "id": "idea2",
      "type": "text",
      "x": 350,
      "y": -50,
      "width": 200,
      "height": 80,
      "text": "## Supporting Point 1\n\nDetails..."
    },
    {
      "id": "idea3",
      "type": "text",
      "x": 350,
      "y": 100,
      "width": 200,
      "height": 80,
      "text": "## Supporting Point 2\n\nMore details..."
    }
  ],
  "edges": [
    {
      "id": "e1",
      "fromNode": "idea1",
      "fromSide": "right",
      "toNode": "idea2",
      "toSide": "left",
      "toEnd": "arrow"
    },
    {
      "id": "e2",
      "fromNode": "idea1",
      "fromSide": "right",
      "toNode": "idea3",
      "toSide": "left",
      "toEnd": "arrow"
    }
  ]
}

Project Board with Groups

{
  "nodes": [
    {
      "id": "todo-group",
      "type": "group",
      "x": 0,
      "y": 0,
      "width": 300,
      "height": 400,
      "label": "To Do",
      "color": "1"
    },
    {
      "id": "progress-group",
      "type": "group",
      "x": 350,
      "y": 0,
      "width": 300,
      "height": 400,
      "label": "In Progress",
      "color": "3"
    },
    {
      "id": "done-group",
      "type": "group",
      "x": 700,
      "y": 0,
      "width": 300,
      "height": 400,
      "label": "Done",
      "color": "4"
    },
    {
      "id": "task1",
      "type": "text",
      "x": 20,
      "y": 50,
      "width": 260,
      "height": 80,
      "text": "## Task 1\n\nDescription of first task"
    },
    {
      "id": "task2",
      "type": "text",
      "x": 370,
      "y": 50,
      "width": 260,
      "height": 80,
      "text": "## Task 2\n\nCurrently working on this"
    },
    {
      "id": "task3",
      "type": "text",
      "x": 720,
      "y": 50,
      "width": 260,
      "height": 80,
      "text": "## Task 3\n\n~~Completed task~~"
    }
  ],
  "edges": []
}

Research Canvas with Files and Links

{
  "nodes": [
    {
      "id": "central",
      "type": "text",
      "x": 200,
      "y": 200,
      "width": 200,
      "height": 100,
      "text": "# Research Topic\n\nMain research question",
      "color": "6"
    },
    {
      "id": "notes1",
      "type": "file",
      "x": 0,
      "y": 0,
      "width": 180,
      "height": 150,
      "file": "Research/Literature Review.md"
    },
    {
      "id": "notes2",
      "type": "file",
      "x": 450,
      "y": 0,
      "width": 180,
      "height": 150,
      "file": "Research/Methodology.md"
    },
    {
      "id": "source1",
      "type": "link",
      "x": 0,
      "y": 350,
      "width": 180,
      "height": 100,
      "url": "https://scholar.google.com"
    },
    {
      "id": "source2",
      "type": "link",
      "x": 450,
      "y": 350,
      "width": 180,
      "height": 100,
      "url": "https://arxiv.org"
    }
  ],
  "edges": [
    {
      "id": "e1",
      "fromNode": "central",
      "toNode": "notes1",
      "toEnd": "arrow",
      "label": "literature"
    },
    {
      "id": "e2",
      "fromNode": "central",
      "toNode": "notes2",
      "toEnd": "arrow",
      "label": "methods"
    },
    {
      "id": "e3",
      "fromNode": "central",
      "toNode": "source1",
      "toEnd": "arrow"
    },
    {
      "id": "e4",
      "fromNode": "central",
      "toNode": "source2",
      "toEnd": "arrow"
    }
  ]
}

Flowchart

{
  "nodes": [
    {
      "id": "start",
      "type": "text",
      "x": 100,
      "y": 0,
      "width": 150,
      "height": 60,
      "text": "**Start**",
      "color": "4"
    },
    {
      "id": "decision",
      "type": "text",
      "x": 75,
      "y": 120,
      "width": 200,
      "height": 80,
      "text": "## Decision\n\nIs condition true?",
      "color": "3"
    },
    {
      "id": "yes-path",
      "type": "text",
      "x": -100,
      "y": 280,
      "width": 150,
      "height": 60,
      "text": "**Yes Path**\n\nDo action A"
    },
    {
      "id": "no-path",
      "type": "text",
      "x": 300,
      "y": 280,
      "width": 150,
      "height": 60,
      "text": "**No Path**\n\nDo action B"
    },
    {
      "id": "end",
      "type": "text",
      "x": 100,
      "y": 420,
      "width": 150,
      "height": 60,
      "text": "**End**",
      "color": "1"
    }
  ],
  "edges": [
    {
      "id": "e1",
      "fromNode": "start",
      "fromSide": "bottom",
      "toNode": "decision",
      "toSide": "top",
      "toEnd": "arrow"
    },
    {
      "id": "e2",
      "fromNode": "decision",
      "fromSide": "left",
      "toNode": "yes-path",
      "toSide": "top",
      "toEnd": "arrow",
      "label": "Yes"
    },
    {
      "id": "e3",
      "fromNode": "decision",
      "fromSide": "right",
      "toNode": "no-path",
      "toSide": "top",
      "toEnd": "arrow",
      "label": "No"
    },
    {
      "id": "e4",
      "fromNode": "yes-path",
      "fromSide": "bottom",
      "toNode": "end",
      "toSide": "left",
      "toEnd": "arrow"
    },
    {
      "id": "e5",
      "fromNode": "no-path",
      "fromSide": "bottom",
      "toNode": "end",
      "toSide": "right",
      "toEnd": "arrow"
    }
  ]
}

ID Generation

Node and edge IDs must be unique strings. Obsidian generates 16-character hexadecimal IDs.

Example format: a1b2c3d4e5f67890

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
• JSON Canvas GitHub