json-canvas

$npx skills add kepano/obsidian-skills --skill json-canvas
SKILL.md

Json Canvas

This skill enables skills-compatible agents to create and edit valid JSON Canvas files (`.canvas`) used in Obsidian and other applications. 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/). A canvas file contains two top-level arrays:

JSON Canvas Skill

This skill enables skills-compatible agents 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.

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

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.
{
  "id": "6f0ad84f44ce9c17",
  "type": "text",
  "x": 0,
  "y": 0,
  "width": 400,
  "height": 200,
  "text": "# Hello World\n\nThis is **Markdown** content."
}

Newline Escaping (Common Pitfall)

In JSON, newline characters inside strings must be represented as \n. Do not use the literal sequence \\n in a .canvas file—Obsidian will render it as the characters \ and n instead of a line break.
Examples:
{ "type": "text", "text": "Line 1\nLine 2" } { "type": "text", "text": "Line 1\\nLine 2" }
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.).
{
  "id": "a1b2c3d4e5f67890",
  "type": "file",
  "x": 500,
  "y": 0,
  "width": 400,
  "height": 300,
  "file": "Attachments/diagram.png"
}

{
  "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.
{
  "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.
{
  "id": "d4e5f6789012345a",
  "type": "group",
  "x": -50,
  "y": -50,
  "width": 1000,
  "height": 600,
  "label": "Project Overview",
  "color": "4"
}

{
  "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.
{
  "id": "f67890123456789a",
  "fromNode": "6f0ad84f44ce9c17",
  "toNode": "a1b2c3d4e5f67890"
}

{
  "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

{
  "color": "#FF0000"
}
`### Preset Colors`
{
  "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

{
  "nodes": [
    {
      "id": "8a9b0c1d2e3f4a5b",
      "type": "text",
      "x": 0,
      "y": 0,
      "width": 300,
      "height": 150,
      "text": "# Main Idea\n\nThis is the central concept."
    },
    {
      "id": "1a2b3c4d5e6f7a8b",
      "type": "text",
      "x": 400,
      "y": -100,
      "width": 250,
      "height": 100,
      "text": "## Supporting Point A\n\nDetails here."
    },
    {
      "id": "2b3c4d5e6f7a8b9c",
      "type": "text",
      "x": 400,
      "y": 100,
      "width": 250,
      "height": 100,
      "text": "## Supporting Point B\n\nMore 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`
{
  "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 1\n\nImplement feature X"
    },
    {
      "id": "9c0d1e2f3a4b5c6d",
      "type": "text",
      "x": 370,
      "y": 50,
      "width": 260,
      "height": 80,
      "text": "## Task 2\n\nReview PR #123",
      "color": "2"
    },
    {
      "id": "0d1e2f3a4b5c6d7e",
      "type": "text",
      "x": 720,
      "y": 50,
      "width": 260,
      "height": 80,
      "text": "## Task 3\n\n~~Setup CI/CD~~"
    }
  ],
  "edges": []
}
`### Research Canvas with Files and Links`
{
  "nodes": [
    {
      "id": "1e2f3a4b5c6d7e8f",
      "type": "text",
      "x": 300,
      "y": 200,
      "width": 400,
      "height": 200,
      "text": "# Research Topic\n\n## Key Questions\n\n- 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`
{
  "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**\n\nIs 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:
"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