@cubiczan/governed-mcp-gateway

HTTP MCP control plane (default port 7474). Principal on every tools/call and every SSE frame — not a tool catalog.

Production MCP auth often dies when work hops threads or workers. This gateway resolves a Bearer credential to a Principal, injects it into params._meta.cubiczan.principal, repeats it on SSE, enforces allowlists, rotates vaulted secrets in place, and runs a lightweight CHP spend gate before priced tools.

Install / run

npm i -g @cubiczan/governed-mcp-gateway   # or use npx
npx -y @cubiczan/governed-mcp-gateway
# → http://127.0.0.1:7474

From source:

npm install
npm run build
npm start
npm test

Cursor / Claude config

Start the gateway in a terminal (or a process manager), then point the client at the HTTP MCP endpoints:

{
  "mcpServers": {
    "governed-gateway": {
      "url": "http://127.0.0.1:7474/mcp",
      "headers": {
        "Authorization": "Bearer mcp_agt_payops_demo"
      }
    },
    "chp": {
      "command": "npx",
      "args": ["-y", "@cubiczan/chp-mcp"]
    },
    "conductor": {
      "command": "npx",
      "args": ["-y", "@cubiczan/agent-conductor"]
    }
  }
}

Demo keys: mcp_agt_payops_demo, mcp_agt_research_demo, mcp_human_controller_demo.

Stack

┌─────────────────┐     ┌──────────────────────────┐     ┌────────────────────┐
│ Cursor / Claude │────▶│ governed-mcp-gateway     │────▶│ spend-mandate-plane│
│ (MCP client)    │ SSE │ :7474  principal+vault   │ opt │ :7475              │
└────────┬────────┘     └────────────┬─────────────┘     └────────────────────┘
         │                           │
         │ stdio                     │ CHP gate (embedded)
         ▼                           ▼
┌─────────────────┐     ┌──────────────────────────┐
│ @cubiczan/      │     │ @cubiczan/chp-mcp        │
│ agent-conductor │     │ Profile B spend / HITL   │
└─────────────────┘     └──────────────────────────┘

Sister packages: @cubiczan/chp-mcp, @cubiczan/agent-conductor, consensus-hardening-protocol.

API

| Method | Path | Auth | What | |--------|------|------|------| | GET | /health | — | { ok, service } | | POST | /mcp | Bearer | JSON-RPC initialize, tools/list, tools/call | | GET | /mcp/sse | Bearer | SSE with principal on _meta | | POST | /v1/credentials | Human | Put a named secret | | POST | /v1/credentials/:name/rotate | Human | New hash, same name | | POST | /v1/credentials/verify | — | { ok } | | POST | /v1/locks | Human | CHP approve / reject |

curl -sS -H "Authorization: Bearer mcp_agt_payops_demo" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"echo.ping","arguments":{"hello":"world"}}}' \
  http://127.0.0.1:7474/mcp

Notes

• This is an HTTP MCP gateway (JSON-RPC + SSE), not a stdio MCP process. The governed-mcp-gateway bin starts the HTTP server.
• Shared CHP / HTTP / ledger helpers are vendored under src/shared/ (no @cubiczan/shared workspace dep).
• Optional: set SPEND_PLANE_URL to hook the spend-mandate plane before priced tools.

License

MIT