set-category-rules · Yarr Media Stack MCP: Risk & Policy

WHAT IT DOES

What set-category-rules does on Yarr Media Stack

AI agents use set-category-rules to create or update resources in Yarr Media Stack — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Yarr Media Stack environment.

WHY IT NEEDS A POLICY

Why set-category-rules needs a policy

This tool modifies download settings/rules by category within a media stack system (Sonarr/Prowlarr/Overseerr). Configuration changes are reversible (can be reconfigured), so it qualifies as Write rather than Destructive. Severity is medium because misconfiguration could cause unwanted downloads or bandwidth usage, but the effects are not permanent or financial.

From the tool's definition Tool name 'set-category-rules' and description 'Configure download settings by category' indicate modification of configuration data. The verb 'set' and action 'Configure' show this creates or modifies settings reversibly.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set-category-rules Rate-limited

set-category-rules 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": {
    "set-category-rules": {
      "limits": [
        {
          "counter": "set-category-rules_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 Yarr Media Stack, so you can run agents against it safely.

FAQ

Questions about set-category-rules

What does the set-category-rules tool do? +

Configure download settings by category. It is categorised as a Write tool in the Yarr Media Stack MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set-category-rules? +

Register the Yarr Media Stack MCP server in PolicyLayer and add a rule for set-category-rules: 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 Yarr Media Stack. Nothing to install.

What risk level is set-category-rules? +

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

Can I rate-limit set-category-rules? +

Yes. Add a rate_limit block to the set-category-rules 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 set-category-rules completely? +

Set action: deny in the PolicyLayer policy for set-category-rules. 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 set-category-rules? +

set-category-rules is provided by the Yarr Media Stack MCP server (mcpnexus-registry/yarr). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.