What is mcp-figma CLAUDE.md?

Project instructions for Claude Code, an AI coding assistant, working on a bridge between Figma Desktop and AI clients. The project uses a Figma plugin, a local WebSocket relay, and an MCP server to send design actions to the Figma canvas.

Use them when building, running, testing, or changing the mcp-figma project.

They give the coding assistant the project's build commands, architecture, security settings, and development conventions in one place.

How tranhoangtu-it/mcp-figma configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to tranhoangtu-it/mcp-figma. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/tranhoangtu-it/mcp-figma/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/tranhoangtu-it/mcp-figma

Made for: Claude Code.

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/instructions/tranhoangtu-it/mcp-figma/claude-md/github.svg)](https://agentmods.dev/instructions/tranhoangtu-it/mcp-figma/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/tranhoangtu-it/mcp-figma/claude-md"><img src="https://agentmods.dev/badge/instructions/tranhoangtu-it/mcp-figma/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/tranhoangtu-it/mcp-figma/claude-md"><img src="https://agentmods.dev/badge/instructions/tranhoangtu-it/mcp-figma/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 585 This file is loaded in full into every session.

When invoked 585 The same file — it is already loaded in full.

Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

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	$0.00585	$0.00585
Opus 5	$0.00293	$0.00293
Sonnet 5	$0.00117	$0.00117
Haiku 4.5	$0.00059	$0.00059

Measured 9d ago against content hash 444b010360f0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

mcp-figma CLAUDE.md scanned grade A with 1 finding 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

- Never pass design data to `child_process.exec()` (CVE-2025-53967 pattern)

CLAUDE.md · 58 lines

How it starts

The opening of the file, as written. The whole thing — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

MCP server bridging AI clients to Figma Desktop via Plugin API + WebSocket. Three components:

MCP Server (src/mcp-server/) — Exposes 25 design tools via stdio, connects to WS relay
WebSocket Server (src/websocket/) — Relay with token auth, channel routing, heartbeat
Figma Plugin (src/figma-plugin/) — Runs inside Figma Desktop, executes Plugin API calls

Build & Run

npm run build          # Build with tsup
npm run ws             # Start WebSocket relay server (shows session token)
npm run start          # Start MCP server (needs MCP_FIGMA_TOKEN env)
npm run dev            # Watch mode
npm run test           # Run all tests
npm run test:ws        # Run WebSocket tests only

Architecture

AI Client → MCP (stdio) → MCP Server → WebSocket (127.0.0.1:3055, token auth) → Figma Plugin → Figma Canvas

MCP Server uses stdio transport (stdout = protocol, stderr = logging)
WebSocket relay binds 127.0.0.1 only with per-session random token
Figma Plugin is plain JS (code.js) running in WASM sandbox + HTML UI (ui.html) for WebSocket

Key Conventions

Figma colors use 0-1 RGBA (not 0-255) — all color params are z.number().min(0).max(1)
Plugin code.js is plain JavaScript — Figma sandbox doesn't support TypeScript, modules, or most browser APIs
All logging to stderr — stdout is reserved for MCP stdio transport
Message IDs use crypto.randomUUID() — for request/response correlation over async WebSocket
Tools are organized in modular files under src/mcp-server/tools/ by function category
Shared schemas and constants live in src/shared/

Testing

Tests use Node.js built-in test runner with tsx loader:

node --import tsx --test src/websocket/ws-server.test.ts

Figma Plugin cannot be unit tested outside Figma — integration testing requires Figma Desktop with plugin imported from manifest.

Read the full file on GitHub · 58 lines

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.

9d ago First seen · 58 lines · 585 tokens per session scan A 444b010360f0

Subscribe to this mod's changes

mcp-figma CLAUDE.md is an instructions file published in the GitHub repository tranhoangtu-it/mcp-figma (0 stars, last pushed 5mo ago), licensed MIT. It adds 585 tokens to every session, about $0.0029 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

ai claude design-tools figma mcp model-context-protocol

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AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

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AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

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vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

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mcp-figma: Instructions file for Claude Code