vna_save_state · Copper Mountain Vna MCP: Risk & Policy

WHAT IT DOES

What vna_save_state does on Copper Mountain Vna

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

WHY IT NEEDS A POLICY

Why vna_save_state needs a policy

This tool creates or modifies a configuration file by persisting the current state of a Vector Network Analyzer. This is a Write operation (creates/updates data reversibly). The blast radius is low because saving configuration state does not alter instrument behavior, affect measurements, trigger calibration, execute arbitrary code, or cause financial impact. The operation is fully reversible.

From the tool's definition Tool name 'vna_save_state' and description 'Save current VNA configuration to file' indicate file creation/writing. The action is reversible—saved configurations can be overwritten or deleted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vna_save_state Rate-limited

vna_save_state 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": {
    "vna_save_state": {
      "limits": [
        {
          "counter": "vna_save_state_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 Copper Mountain Vna, so you can run agents against it safely.

FAQ

Questions about vna_save_state

What does the vna_save_state tool do? +

Save current VNA configuration to file. It is categorised as a Write tool in the Copper Mountain Vna MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on vna_save_state? +

Register the Copper Mountain Vna MCP server in PolicyLayer and add a rule for vna_save_state: 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 Copper Mountain Vna. Nothing to install.

What risk level is vna_save_state? +

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

Can I rate-limit vna_save_state? +

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

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

vna_save_state is provided by the Copper Mountain Vna MCP server (rfingadam/copper-mountain-vna-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.