json-canvas

name json-canvas description 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. JSON Canvas Skill File Structure A canvas file ( .canvas ) contains two top-level arrays following the JSON Canvas Spec 1.0 : { "nodes" : [ ] , "edges" : [ ] } nodes (optional): Array of node objects edges (optional): Array of edge objects connecting nodes Common Workflows 1. Create a New Canvas Create a .canvas file with the base structure {"nodes": [], "edges": []} Generate unique 16-character hex IDs for each node (e.g., "6f0ad84f44ce9c17" ) Add nodes with required fields: id , type , x , y , width , height Add edges referencing valid node IDs via fromNode and toNode Validate : Parse the JSON to confirm it is valid. Verify all fromNode / toNode values exist in the nodes array 2. Add a Node to an Existing Canvas Read and parse the existing .canvas file Generate a unique ID that does not collide with existing node or edge IDs Choose position ( x , y ) that avoids overlapping existing nodes (leave 50-100px spacing) Append the new node object to the nodes array 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 fromNode and toNode to the source and target IDs Optionally set fromSide / toSide (top, right, bottom, left) for anchor points Optionally set label for descriptive text on the edge Append the edge to the edges array Validate : Confirm both fromNode and toNode reference existing node IDs 4. Edit an Existing Canvas Read and parse the .canvas file as JSON 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 id Yes string Unique 16-char hex identifier type Yes string 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 Preset "1" - "6" or hex (e.g., "#FF0000" ) Text Nodes Attribute Required Type Description text 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 file Yes string Path to file within the system subpath 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 url 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 label No string Text label for the group background No string Path to background image backgroundStyle No string cover , ratio , or repeat { "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 id Yes string - Unique identifier fromNode Yes string - Source node ID fromSide No string - top , right , bottom , or left fromEnd No string none none or arrow toNode Yes string - Target node ID toSide No string - top , right , bottom , or left toEnd No string arrow none or arrow color No canvasColor - Line color label 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 "1" Red "2" Orange "3" Yellow "4" Green "5" Cyan "6" 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) x increases right, y increases down; position is the top-left corner 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 id values are unique across both nodes and edges Every fromNode and toNode references an existing node ID Required fields are present for each node type ( text for text nodes, file for file nodes, url for link nodes) type is one of: text , file , link , group fromSide / toSide values are one of: top , right , bottom , left fromEnd / toEnd values are one of: none , arrow Color presets are "1" through "6" or valid hex (e.g., "#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. References JSON Canvas Spec 1.0 JSON Canvas GitHub