create_dataset · Truenas Ws MCP: Risk & Policy

WHAT IT DOES

What create_dataset does on Truenas Ws

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

WHY IT NEEDS A POLICY

Why create_dataset needs a policy

Creating a dataset is a Write operation (it adds new data structures to the storage system). It is not Destructive because datasets can be deleted later, and not Execute because it doesn't run arbitrary code or external commands. Severity is high because misconfiguration or unintended dataset creation in a storage system could consume significant resources, fragment storage, or interfere with system operations.

From the tool's definition Tool description states 'Create a new ZFS dataset' — a reversible creation operation that modifies storage infrastructure.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_dataset Rate-limited

create_dataset 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": {
    "create_dataset": {
      "limits": [
        {
          "counter": "create_dataset_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 Truenas Ws, so you can run agents against it safely.

FAQ

Questions about create_dataset

What does the create_dataset tool do? +

Create a new ZFS dataset. It is categorised as a Write tool in the Truenas Ws 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_dataset? +

Register the Truenas Ws MCP server in PolicyLayer and add a rule for create_dataset: 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 Truenas Ws. Nothing to install.

What risk level is create_dataset? +

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

Can I rate-limit create_dataset? +

Yes. Add a rate_limit block to the create_dataset 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_dataset completely? +

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

create_dataset is provided by the Truenas Ws MCP server (thoriphes/truenas-ws-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.