Borrowing it
Nothing to install: this file belongs to eaccmk/eaccmk_excalidraw-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/eaccmk/eaccmk_excalidraw-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/eaccmk/eaccmk_excalidraw-mcpWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/eaccmk/eaccmk_excalidraw-mcp/claude-md)<a href="https://agentmods.dev/instructions/eaccmk/eaccmk_excalidraw-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/eaccmk/eaccmk_excalidraw-mcp/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/eaccmk/eaccmk_excalidraw-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/eaccmk/eaccmk_excalidraw-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.02343 | $0.02343 |
| Opus 5 | $0.01171 | $0.01171 |
| Sonnet 5 | $0.00469 | $0.00469 |
| Haiku 4.5 | $0.00234 | $0.00234 |
Grade A, and why
eaccmk_excalidraw-mcp CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Excalidraw MCP App Server
Standalone MCP server that streams Excalidraw diagrams as SVG with hand-drawn animations.
Architecture
server.ts → 2 tools (read_me, create_view) + resource + cheat sheet
main.ts → HTTP (Streamable) + stdio transports
src/mcp-app.tsx → ExcalidrawAppCore (widget logic) + ExcalidrawApp (useApp wrapper)
src/mcp-entry.tsx → Production entry point: createRoot + ExcalidrawApp
src/global.css → Animations (stroke draw-on, fade-in) + auto-resize
src/dev.tsx → Dev entry point: mock app + sample elements + control panel
src/dev-mock.ts → Mock MCP App with event simulation (sendToolInput, streamElements, etc.)
index-dev.html → Dev HTML entry (served by vite dev server)
vite.config.dev.ts → Dev-only vite config (resolves from node_modules, no esm.sh externals)
Tools
read_me (text tool, no UI)
Returns a cheat sheet with element format, color palettes, coordinate tips, and examples. The model should call this before create_view.
create_view (UI tool)
Takes elements — a JSON string of standard Excalidraw elements. The widget parses partial JSON during streaming and renders via exportToSvg + morphdom diffing. No Excalidraw React canvas component — pure SVG rendering.
Screenshot as model context: After final render, the SVG is captured as a 512px-max PNG and sent via app.updateModelContext() so the model can see the diagram and iterate on user feedback.
Key Design Decisions
Standard Excalidraw JSON — no extensions
The input is standard Excalidraw element JSON. No label on containers, no start/end on arrows. These are Excalidraw's internal "skeleton" API (convertToExcalidrawElements) — not the standard format.
Why: Standard format means any .excalidraw file's elements array works as input.
Trade-off: Labels require separate text elements with manually computed centered coordinates. The cheat sheet teaches the formula: x = shape.x + (shape.width - text.width) / 2.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 9d ago First seen · 206 lines · 2,343 tokens per session scan A d94205a105f5
eaccmk_excalidraw-mcp CLAUDE.md is an instructions file published in the GitHub repository eaccmk/eaccmk_excalidraw-mcp (0 stars, last pushed 12d ago), licensed MIT. It adds 2,343 tokens to every session, about $0.0117 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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