fusion-mcp

A zero-dependency MCP server that exposes OpenRouter Fusion as a tool any agent can call.

Fusion sends your prompt to a panel of models in parallel (with web search), a judge model compares their answers, and you get back one synthesized answer — stronger than any single model. This wraps it so Claude Code (or any MCP client) can reach Fusion directly instead of going through the OpenRouter web UI.

Tool

fusion_ask

Fusion runs several completions per call (panel + judge), so it costs more than a single model call. Use it where being wrong is costly: research, critique, decisions.

Related MCP server: HydraMCP

Setup

Requires Node ≥ 18 and an OpenRouter API key.

export OPENROUTER_API_KEY=sk-or-...

Wire into Claude Code

claude mcp add fusion -e OPENROUTER_API_KEY=sk-or-... -- node /Users/yoshikondo/fusion-mcp/server.mjs

Or add to your MCP config manually:

{
  "mcpServers": {
    "fusion": {
      "command": "node",
      "args": ["/Users/yoshikondo/fusion-mcp/server.mjs"],
      "env": { "OPENROUTER_API_KEY": "sk-or-..." }
    }
  }
}

Then in a session: "use fusion_ask to research X".

Test

npm test

The test suite spins up a real local HTTP server standing in for OpenRouter and drives a real child-process MCP server over real stdio — nothing internal is mocked.

License

MIT