update_entities · Neo4j Knowledge Graph MCP: Risk & Policy

WHAT IT DOES

What update_entities does on Neo4j Knowledge Graph

AI agents use update_entities to create or update resources in Neo4j Knowledge Graph — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Neo4j Knowledge Graph environment.

WHY IT NEEDS A POLICY

Why update_entities needs a policy

The tool modifies existing entities in the knowledge graph but does not irreversibly delete data (that is delete_entities' role). Updates are reversible through subsequent corrections, making this a Write category rather than Destructive.

From the tool's definition Tool name is 'update_entities' with capability to modify data in a Neo4j graph database. Server description confirms users can 'update' entities and relationships.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_entities Rate-limited

update_entities stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "update_entities": {
      "limits": [
        {
          "counter": "update_entities_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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 Knowledge Graph, so you can run agents against it safely.

FAQ

Questions about update_entities

What does the update_entities tool do? +

update_entities. It is categorised as a Write tool in the Neo4j Knowledge Graph MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_entities? +

Register the Neo4j Knowledge Graph MCP server in PolicyLayer and add a rule for update_entities: 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 Knowledge Graph. Nothing to install.

What risk level is update_entities? +

update_entities is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit update_entities? +

Yes. Add a rate_limit block to the update_entities 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 update_entities completely? +

Set action: deny in the PolicyLayer policy for update_entities. 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 update_entities? +

update_entities is provided by the Neo4j Knowledge Graph MCP server (mjftw/mcp_neo4j_knowledge_graph). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.