CELF · Neo4j Gds MCP: Risk & Policy

WHAT IT DOES

What CELF does on Neo4j Gds

AI agents invoke CELF to trigger actions in Neo4j Gds. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why CELF needs a policy

CELF (Cost-Effective Lazy Forward) is a known graph algorithm for influence maximization. Given the server's stated purpose of executing graph algorithms on Neo4j databases, this tool likely runs a graph algorithm. Empty description lowers confidence. Categorized as Execute since it triggers computation on an external database system.

From the tool's definition Tool name 'CELF' with empty description; server description states tools 'run complex graph algorithms' by 'selecting and executing appropriate parameterised graph algorithms' on Neo4j databases.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

CELF Rate-limited

CELF stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "CELF": {
      "limits": [
        {
          "counter": "celf_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Neo4j Gds, so you can run agents against it safely.

FAQ

Questions about CELF

What does the CELF tool do? +

CELF. It is categorised as a Execute tool in the Neo4j Gds MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on CELF? +

Register the Neo4j Gds MCP server in PolicyLayer and add a rule for CELF: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Neo4j Gds. Nothing to install.

What risk level is CELF? +

CELF is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit CELF? +

Yes. Add a rate_limit block to the CELF rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block CELF completely? +

Set action: deny in the PolicyLayer policy for CELF. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides CELF? +

CELF is provided by the Neo4j Gds MCP server (neo4j-contrib/gds-agent). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.