OpenFeature

You run a local MCP server that helps your OpenFeature SDKs install and configure themselves, while supporting the Open Feature Remote Evaluation Protocol (OFREP) over stdio. This keeps feature flag guidance and evaluations close at hand during development and testing.

How to use

To connect your client tools to the local OpenFeature MCP server, choose your preferred transport and point it at the local stdio MCP instance. The server exposes guidance prompts for OpenFeature SDK installation and OFREP evaluations, so your tooling can fetch installation steps and evaluate feature flags without leaving your editor or CLI.

How to install

Prerequisites you need before running the MCP server locally:

• Node.js 18+ installed on your machine
• A working npm or npx setup in your shell

Install the MCP package and run it via the stdio transport. You can use NPX to fetch and run the local MCP without a global install, or install the package globally if you prefer. Follow the concrete examples below to configure your MCP client.

// NPX-based local MCP usage (preferred for quick start)
// Client commands shown here map to the stdio transport exposed by the MCP server
npx -y @openfeature/mcp

// Global install option (alternative)
npm install -g @openfeature/mcp

{
  "mcpServers": {
    "openfeature": {
      "command": "npx",
      "args": ["-y", "@openfeature/mcp"]
    }
  }
}

Additional setup notes

If you prefer different clients, you can configure them to use the stdio transport by providing the same command and arguments structure in their MCP settings. The key pieces you need are the command (npx) and the argument list that includes the MCP package name (@openfeature/mcp). Logs from the MCP server go to stderr, while protocol messages flow to stdout.

Configuration references for common clients

Cursor, VS Code, Claude Code, Windsurf, and Claude Desktop provide ready-made snippets you can copy into your environment to connect to the local MCP server. Here are representative configurations showing the required command and arguments for the stdio transport.

// Cursor: ~/.cursor/mcp_settings.json
{
  "mcpServers": {
    "OpenFeature": {
      "command": "npx",
      "args": ["-y", "@openfeature/mcp"]
    }
  }
}

// VS Code: .continue/config.json
{
  "mcpServers": {
    "OpenFeature": {
      "command": "npx",
      "args": ["-y", "@openfeature/mcp"]
    }
  }
}

// Claude Code: CLI add
claude mcp add --transport stdio openfeature npx -y @openfeature/mcp

// Windsurf raw config
{
  "mcpServers": {
    "OpenFeature": {
      "command": "npx",
      "args": ["-y", "@openfeature/mcp"]
    }
  }
}

// Claude Desktop
{
  "mcpServers": {
    "openfeature": {
      "command": "npx",
      "args": ["-y", "@openfeature/mcp"]
    }
  }
}

Available tools

install_openfeature_sdk

Fetches Markdown instructions for installing the OpenFeature SDK for a given technology and can augment prompts with provider-specific installation notes.

ofrep_flag_eval

Evaluate feature flags via OpenFeature Remote Evaluation Protocol (OFREP). Supports single or bulk evaluation with optional context and authentication.