grains-mcp

An MCP server for Grains — build and deploy a hosted agent to grains.run without leaving Claude.

It's a thin client over the Grains control-plane API. Every tool call acts as one Grains user, authenticated by that user's deploy token.

Tools

Setup

Requires a Grains deploy token (from the dashboard, or grains CLI). Then add the server to Claude Code (~/.claude/mcp.json or project .mcp.json):

{
  "mcpServers": {
    "grains": {
      "command": "grains-mcp",
      "env": {
        "GRAINS_API_URL": "https://api.grains.run",
        "GRAINS_DEPLOY_TOKEN": "grains_dt_your_token_here"
      }
    }
  }
}

(Until custom domains are live, GRAINS_API_URL is the API Gateway URL.)

Then, in Claude: "scaffold a URL-summarizer agent and deploy it to Grains." Claude calls grains_scaffold, writes the files, calls grains_deploy, and you can grains_invoke it — all in one conversation.

Transports

• stdio (default) — for the Claude Code config above.
• streamable-http — grains-mcp --http --port 8080, for hosting at mcp.grains.run (hosted OAuth-backed deployment is a follow-up; today the server authenticates with the deploy token from its env).