cribl_restartWorkerGroup · Cribl MCP: Risk & Policy

WHAT IT DOES

What cribl_restartWorkerGroup does on Cribl

AI agents invoke cribl_restartWorkerGroup to trigger actions in Cribl. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why cribl_restartWorkerGroup needs a policy

This tool executes an operational action (restart) on infrastructure components. While not destructive (data is not deleted), it triggers external effects that could interrupt data processing pipelines and cause service disruption. The impact depends on arguments (which worker group), classifying it as Execute rather than Read or Write.

From the tool's definition Tool name contains 'restart' and description states it 'Restarts all workers within the default or specified worker group.' Restarting worker groups triggers external operations (service restarts) whose effects depend on which worker group is targeted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

cribl_restartWorkerGroup Rate-limited

cribl_restartWorkerGroup stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "cribl_restartWorkerGroup": {
      "limits": [
        {
          "counter": "cribl_restartworkergroup_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Cribl, so you can run agents against it safely.

FAQ

Questions about cribl_restartWorkerGroup

What does the cribl_restartWorkerGroup tool do? +

Restarts all workers within the default or specified worker group. It is categorised as a Execute tool in the Cribl MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on cribl_restartWorkerGroup? +

Register the Cribl MCP server in PolicyLayer and add a rule for cribl_restartWorkerGroup: 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 Cribl. Nothing to install.

What risk level is cribl_restartWorkerGroup? +

cribl_restartWorkerGroup is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit cribl_restartWorkerGroup? +

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

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

cribl_restartWorkerGroup is provided by the Cribl MCP server (pebbletek/cribl-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.