glyphs-mcp 0.2.6

MCP bridge for AI-assisted type design in GlyphsApp.

Lets Claude, Cursor, or any MCP client read and write font data directly in GlyphsApp — bidirectional, real-time, live in the editor.

MCP Client  ←(stdio/MCP)→  MCP Server  ←(HTTP/localhost)→  GlyphsApp Plugin

Requirements

• Glyphs 3 or 4
• An MCP client
• Python 3.10+ with uv (recommended) or pip
• glyphsets and shaperglot (installed automatically with the MCP package)

Installation

1. Install the GlyphsApp plugin

From Plugin Manager (recommended): Open GlyphsApp, go to Window > Plugin Manager, search for MCP, and click Install.

Manual install: Download GlyphsMCP.glyphsPlugin.zip from the latest release, unzip, and double-click to install.

Restart GlyphsApp. You should see GlyphsMCP under the Window menu.

2. Connect your MCP client

Open Window > GlyphsMCP > Connect and choose your client:

• Claude Code — registers a user-scoped stdio server with the official claude CLI.
• Codex / ChatGPT Desktop — registers the server with codex; both apps share this configuration.
• OpenCode — adds the server to OpenCode's global configuration; restart OpenCode afterward.
• Visual Studio Code — adds the server to your active user profile with code --add-mcp.
• Cursor — safely merges the server into ~/.cursor/mcp.json and backs up an existing file first.
• Other MCP Client — copies a portable mcpServers JSON block to the clipboard.

Glyphs 3 and Glyphs 4 are registered separately as glyphs-3 and glyphs-4, using the port currently configured in each app. If a client CLI is not available to GlyphsApp, the equivalent Terminal command is copied to the clipboard instead.

For manual setup, use the endpoint shown when starting the GlyphsMCP server. For example:

{
  "mcpServers": {
    "glyphs-4": {
      "command": "uvx",
      "args": ["glyphs-mcp"],
      "env": {
        "GLYPHS_URL": "http://127.0.0.1:7746"
      }
    }
  }
}

Claude Desktop now recommends Desktop Extensions (.mcpb) for local MCP servers. A GlyphsMCP Desktop Extension is planned separately and is not installed by this menu yet.

3. Use it

Open a font in GlyphsApp, then ask your AI assistant:

"Run a full color audit on my font and tell me which glyphs are inconsistent"

"Compare the stems across all my lowercase letters"

"Check if my figures are consistent with my letters"

"Make the R 20% wider and harmonize the curves"

"Analize metrics on lowercases"

Tools

Read

Write

Analysis

Analysis tools may mark glyphs in GlyphsApp: red = inconsistent, orange = unreliable, yellow = warning/optical compensation, green = pass. analyze_kerning, analyze_spacing, check_compatibility, and compare_stems also point to matching workflow recipes for broader checks.

RMX Tools

Requires RMX Tools for full functionality. rmx_scale now uses real RMX processing, accepts one value or a per-master list for scale parameters, and defaults allow_fallback=False; native affine fallback must be explicitly enabled. rmx_tune delegates to the loaded RMX Tuner and supports blend and all_masters.

Recipes

Bundled markdown recipes provide ordered workflows for consistency audits, spacing, kerning, master compatibility, proportional scaling, dated-layer cleanup, and Glyphs plugin creation.

Recipe creation and deletion modify files in the installed plugin's Resources/recipes directory.

Advanced

Multi-master support

All tools accept an optional master_id parameter. When omitted, read/write tools use the first master. Analysis tools analyze all masters and return per-master results.

Tools with side effects are explicit: kerning-group analysis can assign groups and color glyphs; auto-kern can write kerning; glyphset coverage can add empty blue-labelled glyphs; box drawing creates or replaces outlines; smart scale modifies outlines and can create backup layers; recipe CRUD writes or deletes markdown files. Use dry-run/preview options where available and save the font before bulk operations.

Menu

The plugin adds a GlyphsMCP submenu under Window in the menu bar:

• Start/Stop Server — toggle the HTTP server
• Connect — register GlyphsMCP with Claude Code, Codex/ChatGPT Desktop, OpenCode, VS Code, Cursor, or copy a generic configuration
• Documentation — open this page in your browser
• Allow Execute Endpoint — enable execute_in_glyphs (off by default for security)

Preferences

How it works

The GlyphsApp plugin runs an HTTP server on 127.0.0.1 using the configured port (7745 by default). All GlyphsApp API calls run on the main thread via a queue + NSTimer bridge for thread safety.

The MCP server is a thin translation layer — it receives MCP tool calls via stdio and forwards them to the plugin URL supplied through GLYPHS_URL.

Roadmap

• Font proofing — Generate proof strings for spacing/kerning evaluation
• Auto-update — Check for updates directly from the GlyphsMCP menu
• Analytics — Optional usage telemetry to guide development priorities

License

MIT — Nicolas Massi www.nico.works