NIGHTGATE-MCP

@odatano/nightgate-mcp is a Model Context Protocol (MCP) server that exposes NIGHTGATE, the Midnight blockchain attestation layer, to AI agents. An agent connected to it can anchor documents on-chain, prove zero-knowledge predicates over hidden document fields, manage disclosure grants, verify everything against live contract state, and poll async jobs — through plain MCP tool calls, without knowing anything about OData, Compact or Midnight.

Wallet lifecycle (connect, send, deploy) is deliberately not exposed: the agent gets a notary, not a wallet.

Highlights

• 15 tools covering verify, prove, anchor and grant — the full NIGHTGATE attestation surface
• Clean negatives: every verification tool returns verified: false when an attestation or proof is absent, never an error
• Scoped agent access: write tools run against a pinned wallet session and can be restricted by an ngat_… agent-grant token (tool allowlist, budget, pinned session)
• Async job model: anchor / prove / grant tools return a job id; get_job_status polls until succeeded / failed
• Zero-install: ships a nightgate-mcp binary — npx @odatano/nightgate-mcp is enough
• Any MCP client: Claude Code, Claude Desktop, Cursor, or a custom @modelcontextprotocol/sdk client

Requirements

Getting a NIGHTGATE instance

The fastest way is the official Docker image published from the NIGHTGATE repo — no Node setup, no host app:

docker run -d --name nightgate -p 4004:4004 \
  -e ENCRYPTION_KEY=$(openssl rand -hex 32) \
  -e NIGHTGATE_HTTP_PASSWORD=change-me \
  -v nightgate-data:/data \
  ghcr.io/odatano/nightgate:latest

The container targets Midnight preprod by default, serves with HTTP basic auth (nightgate / your password), persists its database in the nightgate-data volume, and proves in-process (WASM), so no proof server is needed to start.

Alternatively, any CAP app using the @odatano/nightgate plugin works — e.g. the NIGHTGATE repo itself via npm run dev.

Configuration

Configuration is environment-driven so the same binary works for local dev (basic auth against a cds watch instance) and for a deployed NIGHTGATE behind a reverse proxy (bearer token / agent grants).

For agent operation, create a scoped grant once as the operator (e.g. via curl against NIGHTGATE’s createAgentGrant action) and hand the returned ngat_… token to the agent as NIGHTGATE_TOKEN. The write tools are then limited to the grant’s allowlist, budget and pinned session.

Use with Claude Code

claude mcp add nightgate \
  --env NIGHTGATE_BASE_URL=http://localhost:4004 \
  --env NIGHTGATE_TOKEN=ngat_... \
  -- npx -y @odatano/nightgate-mcp

Or in a project .mcp.json (Claude Code, Cursor and most MCP clients share this shape):

{
  "mcpServers": {
    "nightgate": {
      "command": "npx",
      "args": ["-y", "@odatano/nightgate-mcp"],
      "env": {
        "NIGHTGATE_BASE_URL": "http://localhost:4004",
        "NIGHTGATE_TOKEN": "ngat_..."
      }
    }
  }
}

For a local dev instance with mocked CAP auth, replace NIGHTGATE_TOKEN with NIGHTGATE_USERNAME / NIGHTGATE_PASSWORD.

Tools

Write tools require a connected wallet session (sessionId); creating sessions stays outside MCP by design.

Typical agent flow

1. prepare_document_proof   → payloadHash, contentRoot, per-field proof inputs
2. anchor_document          → { jobId }        (async)
3. get_job_status           → succeeded, on-chain tx
4. prove_field_predicate    → { jobId }        e.g. "carbon_footprint ≤ 80"
5. get_job_status           → succeeded, attestation id
6. verify_predicate         → verified: true   (anyone, crawler-free)

Stack

Sourcecode

github.com/ODATANO/NIGHTGATE-MCP · npm: @odatano/nightgate-mcp