Add new skill :excalidraw-diagram-generator skill

[jun-shiromizu]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• My contribution adds a new instruction, prompt, agent, or skill file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, or skill with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.

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Description

Summary

Add a new skill, excalidraw-diagram-generator, to generate Excalidraw .excalidraw JSON diagrams from natural language requests. It supports multiple diagram types (flowcharts, relationship diagrams, mind maps, architecture, DFD, swimlane, class, sequence, ER) and provides step-by-step guidance and templates. Includes guidance for optional icon library usage via bundled scripts.

Why / Use cases

• Create diagrams directly from Copilot prompts without manual drawing
• Quickly visualize workflows, system architecture, data flows, and entity relations
• Produce reusable .excalidraw files that open in Excalidraw or the VS Code extension

How to use (quick start)

1. Use the skill when asked to “create a diagram / flowchart / architecture / mind map”.
2. Provide a clear description of key entities, steps, and relationships.
3. Output a .excalidraw JSON file and open it in Excalidraw (web or VS Code extension).

Validation / Tests

• npm run skill:validate
• npm run build
• bash scripts/fix-line-endings.sh

Distinct from existing skills

• Focuses specifically on generating Excalidraw-format diagram files (not Mermaid/PlantUML/ASCII).
• Includes templates, scripts, and guidance for diagram construction and optional icon library workflows.

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New collection file.
• New skill file.
• Update to existing instruction, prompt, agent, collection or skill.
• Other (please specify):

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Additional Notes

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[Copilot]

Pull request overview

This PR introduces a new skill called excalidraw-diagram-generator that enables generating Excalidraw diagrams from natural language descriptions. The skill supports multiple diagram types including flowcharts, relationship diagrams, mind maps, architecture diagrams, data flow diagrams, swimlane diagrams, class diagrams, sequence diagrams, and ER diagrams. It includes comprehensive templates, reference documentation, and Python scripts for working with Excalidraw icon libraries.

Changes:

• Added complete skill implementation with SKILL.md, templates, references, and helper scripts
• Integrated skill into the skills documentation table
• Provided 8 diagram templates as starting points for different diagram types

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
skills/excalidraw-diagram-generator/SKILL.md	Main skill documentation with workflow, guidelines, and icon library integration instructions
skills/excalidraw-diagram-generator/templates/*.excalidraw	8 diagram templates for different use cases (flowchart, relationship, mindmap, etc.)
skills/excalidraw-diagram-generator/references/*.md	Schema and element type reference documentation
skills/excalidraw-diagram-generator/scripts/*.py	Python utilities for library splitting, icon insertion, and arrow creation
skills/excalidraw-diagram-generator/scripts/README.md	Documentation for the Python scripts
docs/README.skills.md	Added skill entry to skills table
docs/README.instructions.md	Unrelated formatting change (row reordering)

[aaronpowell]

Would it be worth including a .gitignore file in the scripts folder to avoid the skill generating python artifacts that are inadvertently added to a repo when the skill is used?

[jun-shiromizu]

Would it be worth including a .gitignore file in the scripts folder to avoid the skill generating python artifacts that are inadvertently added to a repo when the skill is used?

Thank you for your review. The .gitignore file under the scripts folder has now been removed. I received a similar report yesterday via PR#624 and have cleaned it up in this PR. Please verify.

[aaronpowell]

I was suggesting to include one in the skill's script folder

[jun-shiromizu]

I was suggesting to include one in the skill's script folder

Based on your suggestion, I came up with the following plan. Does it align with your intent?

• Create a new .gitignore file in the skills/excalidraw-diagram-generator/scripts folder
• The contents of that file are as follows:

# Avoid accidentally committing local Python artifacts produced when running these scripts.

# Byte-compiled / cache files
__pycache__/
*.py[cod]
*$py.class

# Virtual environments (people often create these next to scripts)
.venv/
venv/
env/
ENV/

# Tool caches
.pytest_cache/
.mypy_cache/
.ruff_cache/
.tox/
.nox/

# Coverage outputs
.coverage
.coverage.*
htmlcov/

# Packaging/build outputs (rare here, but harmless)
build/
dist/
*.egg-info/
.eggs/

# OS cruft
.DS_Store
Thumbs.db

[aaronpowell]

Looks good