Create Excalidraw Agent

[GeorgeNgMsft]

Add Excalidraw Agent for AI-Powered Diagram Generation

Summary
Adds a new excalidraw TypeAgent that converts documentation, markdown, Visio XML exports, Mermaid
diagrams, and plain-text architecture descriptions into https://excalidraw.com/ diagram files using
AI. The agent integrates with the existing TypeAgent dispatcher and agent provider infrastructure.

What's Changed
New package: ts/packages/agents/excalidraw/

• excalidrawActionSchema.ts — Defines two actions:
  • createDiagram — accepts sourceContent, sourceType (markdown | text | visio-xml | mermaid |
    architecture), optional diagramTitle, and optional outputPath
  • exportDiagram — writes provided Excalidraw JSON to a specified path
• excalidrawActionHandler.ts — Calls the OpenAI chat model with a structured system prompt that
  instructs the LLM to output valid Excalidraw JSON (type, version, elements[], appState). Writes the
  resulting .excalidraw file to the user-specified path, or defaults to ~/Documents/ with a timestamped
  filename.
• excalidrawManifest.json — Agent manifest for TypeAgent discovery

Agent registration: ts/packages/defaultAgentProvider/

• Registered in config.json, config.all.json, and config.agent.json with execMode: "dispatcher"
• Added excalidraw-agent as a workspace dependency

Usage Examples

▎ "Create an Excalidraw diagram from this architecture document"
▎ "Convert this Mermaid diagram to an Excalidraw file and save it to C:\diagrams\arch.excalidraw"
▎ "Turn this Visio XML into an Excalidraw diagram"

Testing

• pnpm run build excalidraw-agent passes (114 tasks, tsc + asc compilation)
• Schema compiles to excalidrawSchema.pas.json in dist/

Notes

• Output defaults to ~/Documents/<title>_.excalidraw when no path is provided
  (cross-platform: works on Windows and Unix)
• The LLM prompt includes explicit Excalidraw JSON structure guidance (elements, text binding,
  arrows, colors, layout) to maximize diagram quality