Obsidian Canvas

Obsidian Canvas Creator

Create .canvas files that Obsidian will accept without stripping groups, edges, or nodes.

ID Generation

Generate ALL IDs upfront before building JSON. Use 16-char lowercase hex:

for i in $(seq 1 N); do uuidgen | tr '[:upper:]' '[:lower:]' | tr -d '-' | head -c 16; echo; done

Or use a systematic hex pattern for clarity:

a1b2c3d4e5f60001  (group 1)
a1b2c3d4e5f60010  (first child of group 1)
a1b2c3d4e5f60011  (second child of group 1)
a1b2c3d4e5f6e001  (edge 1)

Critical Rules

These are non-negotiable. Violating ANY of them causes Obsidian to silently strip nodes:

1. Every node MUST have "styleAttributes":{} — Obsidian's proprietary field. Without it, nodes (especially groups) get dropped on re-serialization.
2. Use 16-char hex IDs — Human-readable IDs like "group-work" cause parser issues. Use hex: "a1b2c3d4e5f60001".
3. Groups BEFORE children in the array — Nodes are z-indexed by array position. Groups render behind children, so they must appear earlier.
4. Spatial containment is implicit — No children or parentId field exists. A node is "inside" a group purely by having its bounds within the group's bounds. Children must be FULLY contained.
5. Always include metadata block — {"version":"1.0-1.0","frontmatter":{}}. Prevents unnecessary re-serialization.
6. Edges MUST include fromSide/toSide — Despite being optional in the JSON Canvas spec, Obsidian fails to render edges without them. Values: "top", "right", "bottom", "left".
7. Color is a string — "1" through "6" (presets) or "#RRGGBB". Never use integers.
8. Close the canvas tab before writing — If the canvas is open in Obsidian, its in-memory state will overwrite your file on auto-save. Warn the user to close it first.
9. No custom object/array properties on nodes — Obsidian's custom JSON serializer adds trailing commas for unknown object/array properties, producing invalid JSON. Only styleAttributes:{} is safe.

Node Types Reference

Common Properties (all nodes)

Text Node

Group Node

File Node

Link Node

Edge

Color Reference

Hex values also work: "#FF0000", "#000000", etc.

Sizing Guide

Width: (character_count * 9) + 40 px, round up to nearest 20.

• 40px = ~20px padding each side
• Bold text: use ~10px/char
• Emojis: count as ~2 chars

Height: 60px for single line. 80-90px if text may wrap.

Group padding: 20-30px margin on each side. Group label takes ~40px at top, so first child y should be group y + 60 minimum.

Minimal Working Template

{
	"nodes":[
		{"id":"a1b2c3d4e5f60001","type":"group","x":-20,"y":-20,"width":560,"height":200,"color":"6","label":"My Group","styleAttributes":{}},
		{"id":"a1b2c3d4e5f60010","type":"text","text":"First item","x":30,"y":60,"width":200,"height":60,"styleAttributes":{}},
		{"id":"a1b2c3d4e5f60011","type":"text","text":"Second item","x":280,"y":60,"width":200,"height":60,"styleAttributes":{}}
	],
	"edges":[
		{"id":"a1b2c3d4e5f6e001","fromNode":"a1b2c3d4e5f60010","fromSide":"right","toNode":"a1b2c3d4e5f60011","toSide":"left"}
	],
	"metadata":{
		"version":"1.0-1.0",
		"frontmatter":{}
	}
}

Workflow

1. Gather content — Ask user what nodes, groups, and connections they need
2. Generate IDs — Run the uuidgen one-liner for all needed IDs (or use systematic hex pattern)
3. Calculate sizing — Use the width formula per node. Pick consistent heights.
4. Layout — Position groups first. Place children within group bounds (with margins). Stack groups vertically with ~60px gaps.
5. Build JSON — Groups BEFORE children in nodes array. Add styleAttributes:{} to every node. Include metadata.
6. Warn user — Tell them to close the canvas tab in Obsidian if it's open
7. Write file — Use the Write tool to create the .canvas file
8. Verify — Ask user to open in Obsidian and confirm groups/edges persist