Skills excalidraw
Generate hand-drawn style diagrams, flowcharts, and architecture diagrams as PNG images from Excalidraw JSON
install
source · Clone the upstream repo
git clone https://github.com/openclaw/skills
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/openclaw/skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/a-anand-91119/excalidraw" ~/.claude/skills/clawdbot-skills-excalidraw && rm -rf "$T"
manifest:
skills/a-anand-91119/excalidraw/SKILL.mdsource content
Excalidraw Diagram Generator
Generate beautiful hand-drawn style diagrams rendered as PNG images.
Workflow
- Generate JSON — Write Excalidraw element array based on what the user wants
- Save to file — Write JSON to
/tmp/<name>.excalidraw - Render —
node <skill_dir>/scripts/render.js /tmp/<name>.excalidraw /tmp/<name>.png - Send — Send the PNG via message tool with
filePath
Quick Reference
node <skill_dir>/scripts/render.js input.excalidraw output.png
Element Types
| Type | Shape | Key Props |
|---|---|---|
| Box | x, y, width, height |
| Oval | x, y, width, height |
| Decision | x, y, width, height |
| Arrow | connects shapes (see Arrow Binding below) |
| Line | x, y, points: [[0,0],[dx,dy]] |
| Label | x, y, text, fontSize, fontFamily (1=hand, 2=sans, 3=code) |
Styling (all shapes)
{ "strokeColor": "#1e1e1e", "backgroundColor": "#a5d8ff", "fillStyle": "hachure", "strokeWidth": 2, "roughness": 1, "strokeStyle": "solid" }
fillStyle:
hachure (diagonal lines), cross-hatch, solid
roughness: 0=clean, 1=hand-drawn (default), 2=very sketchy
Arrow Binding (IMPORTANT)
Always use
/from
bindings for arrows. The renderer auto-calculates edge intersection points — no manual coordinate math needed.to
Simple arrow (straight, between two shapes)
{"type":"arrow","id":"a1","from":"box1","to":"box2","strokeColor":"#1e1e1e","strokeWidth":2,"roughness":1}
That's it. No x, y, or points needed. The renderer computes start/end at shape edges.
Multi-segment arrow (routed path with waypoints)
For arrows that need to go around obstacles, use
absolutePoints with intermediate waypoints:
{ "type":"arrow","id":"a2","from":"box3","to":"box1", "absolutePoints": true, "points": [[375,500],[30,500],[30,127],[60,127]], "strokeColor":"#1e1e1e","strokeWidth":2,"roughness":1 }
- First point = near source shape edge (will snap to actual edge)
- Last point = near target shape edge (will snap to actual edge)
- Middle points = absolute waypoint coordinates for routing
Arrow labels
Place a separate text element near the arrow midpoint:
{"type":"text","id":"label","x":215,"y":98,"width":85,"height":16,"text":"sends data","fontSize":10,"fontFamily":1,"strokeColor":"#868e96"}
Arrow styles
— dashed line"strokeStyle":"dashed"
— bidirectional arrow"startArrowhead": true
Template: Flowchart with Bindings
{ "type": "excalidraw", "version": 2, "elements": [ {"type":"rectangle","id":"start","x":150,"y":50,"width":180,"height":60,"strokeColor":"#1e1e1e","backgroundColor":"#b2f2bb","fillStyle":"hachure","strokeWidth":2,"roughness":1}, {"type":"text","id":"t1","x":200,"y":65,"width":80,"height":30,"text":"Start","fontSize":20,"fontFamily":1,"strokeColor":"#1e1e1e"}, {"type":"arrow","id":"a1","from":"start","to":"decision","strokeColor":"#1e1e1e","strokeWidth":2,"roughness":1}, {"type":"diamond","id":"decision","x":140,"y":170,"width":200,"height":120,"strokeColor":"#1e1e1e","backgroundColor":"#ffec99","fillStyle":"hachure","strokeWidth":2,"roughness":1}, {"type":"text","id":"t2","x":185,"y":215,"width":110,"height":30,"text":"Condition?","fontSize":18,"fontFamily":1,"strokeColor":"#1e1e1e","textAlign":"center"}, {"type":"arrow","id":"a2","from":"decision","to":"process","strokeColor":"#1e1e1e","strokeWidth":2,"roughness":1}, {"type":"rectangle","id":"process","x":150,"y":350,"width":180,"height":60,"strokeColor":"#1e1e1e","backgroundColor":"#a5d8ff","fillStyle":"hachure","strokeWidth":2,"roughness":1}, {"type":"text","id":"t3","x":190,"y":365,"width":100,"height":30,"text":"Process","fontSize":20,"fontFamily":1,"strokeColor":"#1e1e1e"} ] }
Layout Guidelines
- Node size: 140-200 × 50-70 px
- Diamond: 180-200 × 100-120 px (taller for text)
- Vertical spacing: 60-100 px between nodes
- Horizontal spacing: 80-120 px between nodes
- Text: Position inside shape manually (offset ~15-30px from top-left of shape)
- Arrow labels: Place as separate text elements near midpoint of arrow path
Color Palette
Fills:
#a5d8ff (blue), #b2f2bb (green), #ffec99 (yellow), #ffc9c9 (red), #d0bfff (purple), #f3d9fa (pink), #fff4e6 (cream)
Strokes: #1e1e1e (dark), #1971c2 (blue), #2f9e44 (green), #e8590c (orange), #862e9c (purple)
Labels: #868e96 (gray, for annotations)
Tips
- Every element needs a unique
(required for binding!)id - Use
/from
on arrows — don't calculate coordinates manuallyto
for clean diagrams,roughness:0
for sketchy feel1- Text
for hand-drawn,fontFamily:1
for code3 - Group related elements spatially, color-code by type
- For nested layouts, use a large background rectangle as a container