WhisperGraph is a graph database of internet infrastructure: 7.39B nodes, 39B edges, and 5.6M threat-intelligence edges mapping DNS resolution, domain hierarchy, BGP routing, IP allocation, GeoIP, web hyperlinks, email infrastructure, DNSSEC, WHOIS, and threat feeds.

This is the open-source MCP server for it. It exposes WhisperGraph to any MCP client (Claude Desktop, Claude Code, Cursor, …) as one Cypher query tool plus read-only schema-introspection and threat-assessment tools. It validates every query against a safety rule set, then relays it to the hosted WhisperGraph API using your API key.

Learn more: WhisperGraph intro · Cypher API reference · Query guide · Cypher syntax · Functions · Best practices · MCP setup

Quick start

You need a WhisperGraph API key — get a free one.

Claude Desktop / Claude Code / Cursor (stdio)

Add this to your MCP client config:

{
  "mcpServers": {
    "whisper-graph": {
      "command": "npx",
      "args": ["-y", "@whisper-security/whisper-graph-mcp"],
      "env": { "WHISPER_API_KEY": "your-api-key" }
    }
  }
}

Or with Claude Code:

claude mcp add whisper-graph -e WHISPER_API_KEY=your-api-key -- npx -y @whisper-security/whisper-graph-mcp

Hosted remote server (no install)

Whisper also runs a hosted MCP server at https://mcp.whisper.security — point any MCP client that supports remote servers at it and authenticate with your API key. Self-hosting this repo is for teams who want to run the MCP layer in their own environment. See How to set up.

Tools

All six tools are read-only.

| Tool | What it does | | ------------------- | --------------------------------------------------------------------------------------------------------------- | | query | Execute a Cypher query against WhisperGraph. Validated against a safety rule set before it reaches the backend. | | list_labels | List every node label with counts. Call it before writing a query when you're unsure which label to anchor on. | | describe_label | Confirm a label exists and enumerate its property keys. | | explain_indicator | Threat assessment for an IP, hostname, CIDR, or ASN — score, level, factors, sources. | | whisper_history | Historical WHOIS or BGP data for an indicator. | | domain_variants | Typosquatting / brand-protection variants of a domain, checked against the graph. |

Resources

Six MCP resources: the full schema, the relationship map, a Cypher function reference, a query cookbook, plus live whisper://stats and whisper://quota.

Prompts

Eight investigation-workflow prompt templates: investigate-ip, map-attack-surface, compare-domains, blast-radius, threat-triage, whois-pivot, bgp-investigation, typosquat-sweep.

Self-hosting (Docker / HTTP)

For remote or team deployments, run the server over Streamable HTTP:

docker run -p 8080:8080 -e MCP_TRANSPORT=http \
  ghcr.io/whisper-sec/whisper-graph-mcp:latest

Or with Docker Compose:

docker compose up

In HTTP mode the server does not authenticate inbound requests — it relays the caller's X-API-Key or Authorization: Bearer header to the hosted WhisperGraph API, falling back to the WHISPER_API_KEY environment variable when no header is present. Put it behind your own gateway if you need access control.

Configuration

All configuration is via environment variables.

| Variable | Default | Description | | -------------------------- | -------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- | | WHISPER_API_KEY | (none) | Your WhisperGraph API key. Get a free one. | | MCP_TRANSPORT | stdio | stdio for local CLI use, http for remote/Docker. | | HTTP_HOST | 0.0.0.0 | Bind host for the HTTP transport. | | HTTP_PORT | 8080 | Bind port for the HTTP transport. | | WHISPER_ALLOWED_HOSTS | (none) | Comma-separated Host header allowlist for DNS-rebinding protection in HTTP mode. Leave empty only behind a trusted gateway. | | WHISPER_DB_URL | https://graph.whisper.security | Base URL of the hosted WhisperGraph API. | | WHISPER_QUERY_TIMEOUT_MS | 60000 | Hard per-query deadline forwarded to the API. | | WHISPER_DB_TIMEOUT_MS | 10000 | HTTP timeout for non-query calls. | | LOG_LEVEL | info | debug, info, warn, or error. |

Development

npm install
npm run dev       # run from source over stdio
npm test          # unit + integration tests (no secrets needed)
npm run build     # bundle to dist/
npm run lint      # eslint
npm run typecheck # tsc --noEmit

The test suite runs entirely offline against a fake backend — no API key required.

Contributing

Contributions are welcome. See CONTRIBUTING.md and our Code of Conduct. Security issues: see SECURITY.md.

License

Apache-2.0. "Whisper", the Whisper logo, and "WhisperGraph" are trademarks of Whisper Security — see NOTICE.