vna_set_center_span · Copper Mountain Vna MCP: Risk & Policy

WHAT IT DOES

What vna_set_center_span does on Copper Mountain Vna

AI agents use vna_set_center_span 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_set_center_span needs a policy

This tool modifies VNA frequency parameters (center and span) which changes the measurement configuration. This is a Write operation—it creates or modifies device settings reversibly. It does not execute arbitrary code, delete data, or move money.

From the tool's definition Tool name 'vna_set_center_span' and description 'Configure frequency via center and span' indicate modification of Vector Network Analyzer settings.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vna_set_center_span Rate-limited

vna_set_center_span 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_set_center_span": {
      "limits": [
        {
          "counter": "vna_set_center_span_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_set_center_span

What does the vna_set_center_span tool do? +

Configure frequency via center and span. 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_set_center_span? +

Register the Copper Mountain Vna MCP server in PolicyLayer and add a rule for vna_set_center_span: 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_set_center_span? +

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

Can I rate-limit vna_set_center_span? +

Yes. Add a rate_limit block to the vna_set_center_span 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_set_center_span completely? +

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

vna_set_center_span 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.