onyx MCP

This is the official onyx Model Context Protocol (or "MCP" for short) server.

Prerequisites

• Node.js version as specified in .node-version file
• If you are sitting behind an (enterprise) proxy, you might need to set the export NODE_USE_SYSTEM_CA=1 environment variable.

Getting started

Install the CLI globally:

# npm
npm install -g @sit-onyx/modelcontextprotocol

# pnpm
pnpm install -g @sit-onyx/modelcontextprotocol

Now you can run the onyx-mcp command:

onyx-mcp -h

Using with the Gemini CLI

Add this entry to your Gemini settings (in ~/.gemini/settings.json):

{
  "$schema": "https://raw.githubusercontent.com/google-gemini/gemini-cli/main/schemas/settings.schema.json",
  "mcp": {
    "allowed": ["onyx-mcp"]
  },
  "mcpServers": {
    "onyx-mcp": {
      "description": "Information about components of the onyx UI component library",
      "command": "onyx-mcp",
      "args": ["-r"]
    }
  }
}

Save the file and confirm that the MCP has been set up correctly:

gemini mcp list

"Eject" Skills

If you prefer to have the skills as editable markdown on your filesystem, then the --writeSkills flag can be used in the CLI:

onyx-mcp --writeSkills "./skills"

Then configure the onyx-mcp in your coding assistants configuration to exclude the skill capabilities:

onyx-mcp --exclude "skill"

This way the MCP will not provide the skills and avoid duplicated context for the coding agent.

Development/Contributing

Run this command in the monorepo root:

pnpm run dev modelcontextprotocol

This starts the "build" watcher and the @modelcontextprotocol/inspector locally.

You must reload the inspector browser website after changes to the @sit-onyx/modelcontextprotocol source code. Using the "Reconnect" button does not suffice!

Adding Agent Skills

Agent Skills are developed and maintained in the ./src/resources/skills directory. Each skill has its own directory with a single SKILL.md file.

---
name: <skill-name>
description: <skill-description>
license: Apache-2.0
---

Nested/bundled references and other resources are currently not supported.