clone_snapshot · Truenas Ws MCP: Risk & Policy

WHAT IT DOES

What clone_snapshot does on Truenas Ws

AI agents use clone_snapshot 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 clone_snapshot needs a policy

Cloning a snapshot creates a new dataset from an existing snapshot. This is a Write operation as it creates new data/resources (the cloned dataset) without destroying anything. It is reversible since the cloned dataset can be deleted. Severity is medium because misuse could consume significant storage space or create unintended datasets on the TrueNAS system.

From the tool's definition Clone a snapshot to a new dataset

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

clone_snapshot Rate-limited

clone_snapshot 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": {
    "clone_snapshot": {
      "limits": [
        {
          "counter": "clone_snapshot_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 clone_snapshot

What does the clone_snapshot tool do? +

Clone a snapshot to a new 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 clone_snapshot? +

Register the Truenas Ws MCP server in PolicyLayer and add a rule for clone_snapshot: 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 clone_snapshot? +

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

Can I rate-limit clone_snapshot? +

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

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

clone_snapshot 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.