agents_update · CyPerf MCP Server MCP: Risk & Policy

WHAT IT DOES

What agents_update does on CyPerf MCP Server

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

WHY IT NEEDS A POLICY

Why agents_update needs a policy

The tool creates or modifies data (agent properties) in a reversible manner, fitting the Write category. Severity is high because updating agent properties in a network testing platform could alter test behavior, routing, or performance characteristics, potentially affecting production network visibility or test validity.

From the tool's definition Tool name 'agents_update' and description 'Update agent properties' indicate modification of existing agent configurations. Update operations are reversible Write actions.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

agents_update Rate-limited

agents_update 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": {
    "agents_update": {
      "limits": [
        {
          "counter": "agents_update_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 CyPerf MCP Server, so you can run agents against it safely.

FAQ

Questions about agents_update

What does the agents_update tool do? +

[Agents] Update agent properties. It is categorised as a Write tool in the CyPerf 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 agents_update? +

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

What risk level is agents_update? +

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

Can I rate-limit agents_update? +

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

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

agents_update is provided by the CyPerf MCP Server MCP server (keysight/cyperf-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.