create_entities | PolicyLayer

WHAT IT DOES

What create_entities does on MCP DuckDB Knowledge Graph Memory Server

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

THE RISK

Medium Risk

Why create_entities needs a policy

The tool creates new entities in a persisted knowledge graph stored in DuckDB. This is a Write operation—it modifies data reversibly. A misclassified call might inject malicious entities into user knowledge state, pollute the knowledge graph, or contaminate future conversations if the server does not validate entity content.

From the tool's definition create_relations, delete_entities, delete_observations, delete_relations are sibling tools that clearly modify the knowledge graph data; this tool description is 'Create multiple new entities in the knowledge graph'

Documented attack patterns abuse exactly the kind of access create_entities gives an agent:

POLICY

How to control create_entities

PolicyLayer is an MCP gateway — it sits between your AI agents and MCP DuckDB Knowledge Graph Memory Server, and nothing reaches the server without passing your rules. This is the rule we recommend for create_entities:

policy.json

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

create_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.

Create a free account and register MCP DuckDB Knowledge Graph Memory Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More MCP DuckDB Knowledge Graph Memory Server tools

Destructive delete_entities Delete multiple entities and their associated relations from the knowledge graph Destructive delete_observations Delete specific observations from entities in the knowledge graph Destructive delete_relations Delete multiple relations from the knowledge graph Write add_observations Add new observations to existing entities in the knowledge graph Write create_relations Create multiple new relations between entities in the knowledge graph. Relations should be Read search_nodes Search for nodes in the knowledge graph based on a query Read open_nodes Open specific nodes in the knowledge graph by their names

All 8 MCP DuckDB Knowledge Graph Memory Server tools →

Write tools on other servers

M-Team MCP Server download_torrent YouTube MCP Server generate_video_title Android Forensics ADB MCP Server combine_reports 0xarchive web3_signup

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Argument validation → Checking tool call arguments against schema and policy before they run.
Scoped token → Per-person credentials that grant a defined subset of servers and tools.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about create_entities

What does the create_entities tool do? +

Create multiple new entities in the knowledge graph. It is categorised as a Write tool in the MCP DuckDB Knowledge Graph Memory Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_entities? +

Register the MCP DuckDB Knowledge Graph Memory Server MCP server in PolicyLayer and add a rule for create_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 MCP DuckDB Knowledge Graph Memory Server. Nothing to install.

What risk level is create_entities? +

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

Can I rate-limit create_entities? +

Yes. Add a rate_limit block to the create_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 create_entities completely? +

Set action: deny in the PolicyLayer policy for create_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 create_entities? +

create_entities is provided by the MCP DuckDB Knowledge Graph Memory Server MCP server (izumisy/mcp-duckdb-memory-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every MCP DuckDB Knowledge Graph Memory Server tool call.

Start from MCP DuckDB Knowledge Graph Memory Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

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8 MCP DuckDB Knowledge Graph Memory Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.