A local MCP server for creating and synchronising Excalidraw diagrams, using a Node.js program and a local web server.

Use it for agent-assisted diagrams and for keeping diagram changes synchronised with a local Excalidraw canvas.

It gives a coding agent access to an Excalidraw canvas instead of requiring manual diagram work. It needs two environment settings to run.

excalidraw — MCP server for Claude Code and Codex by leocder07: A local MCP server for creating and synchronising Excalidraw…

Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code

/plugin marketplace add leocder07/spectra

Claude Code

/plugin install spectra

Made for: Claude Code, Codex, Cursor, Gemini CLI, OpenCode.

Or install spectra, the plugin that ships this one along with the rest of its 4 commands, 4 agents, 2 hooks, 1 MCP server.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/mcp/leocder07/spectra/excalidraw.svg)](https://agentmods.dev/mcp/leocder07/spectra/excalidraw)

Your own site

<a href="https://agentmods.dev/mcp/leocder07/spectra/excalidraw"><img src="https://agentmods.dev/badge/mcp/leocder07/spectra/excalidraw.svg" alt="Measured on agentmods" height="20"></a>

Per session not measured What this adds to a session before it is invoked.

When invoked not measured Not applicable: nothing here is loaded into a session.

Security scan A 0 findings. Scan, not verified.

Origin original No closer match found in the catalogue.

Security

Grade A, and why

excalidraw 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 5d 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.

.mcp.json · 12 lines

What it actually says

{
  "excalidraw": {
    "command": "node",
    "args": [
      "/Users/leocder/mcp_excalidraw/dist/index.js"
    ],
    "env": {
      "EXPRESS_SERVER_URL": "http://localhost:3000",
      "ENABLE_CANVAS_SYNC": "true"
    }
  }
}

Changes

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.

5d ago First seen · 12 lines scan A ac1aa13fab4a

Subscribe to this mod's changes

excalidraw is an MCP server published in the GitHub repository leocder07/spectra (19 stars, last pushed 2mo ago), licensed MIT. Its token cost is not measured: an MCP server costs its tool schemas, not its config file. 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 2026-08-30.

Design and UX Multi-Agent ai-agents claude code-quality due-diligence

excalidraw

Getting it into your agent

Wrote this? Show the measurements

Grade A, and why

Nothing flagged

What it actually says

What this file has done since we first saw it

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