update_time_machine · NDB MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_time_machine does on NDB MCP Server

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

WHY IT NEEDS A POLICY

Why update_time_machine needs a policy

The tool modifies an existing Time Machine configuration, which is a Write operation—data is being changed but the action is reversible. It does not delete data (Destructive), execute arbitrary code (Execute), or move money (Financial).

From the tool's definition Tool name 'update_time_machine' indicates modification of a Time Machine configuration or state. In Nutanix NDB context, Time Machine is the backup/recovery mechanism.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_time_machine Rate-limited

update_time_machine 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_time_machine": {
      "limits": [
        {
          "counter": "update_time_machine_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 NDB MCP Server, so you can run agents against it safely.

FAQ

Questions about update_time_machine

What does the update_time_machine tool do? +

Update a Time Machine. It is categorised as a Write tool in the NDB MCP 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 update_time_machine? +

Register the NDB MCP Server MCP server in PolicyLayer and add a rule for update_time_machine: 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 NDB MCP Server. Nothing to install.

What risk level is update_time_machine? +

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

Can I rate-limit update_time_machine? +

Yes. Add a rate_limit block to the update_time_machine 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_time_machine completely? +

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

update_time_machine is provided by the NDB MCP Server MCP server (rouxton/ndb-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.