rename_room · Loenn MCP: Risk & Policy

WHAT IT DOES

What rename_room does on Loenn

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

WHY IT NEEDS A POLICY

Why rename_room needs a policy

This tool creates or modifies data (the room name) in a Celeste .bin map file without permanently destroying it. Renaming is reversible, so it does not qualify as Destructive. It is not an Execute operation because it doesn't run arbitrary code or trigger side effects; it simply updates a field.

From the tool's definition The tool description explicitly states 'Rename a room in a map,' which modifies metadata of an existing game map file. This is a reversible write operation—the old name can be changed back.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rename_room Rate-limited

rename_room 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": {
    "rename_room": {
      "limits": [
        {
          "counter": "rename_room_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 Loenn, so you can run agents against it safely.

FAQ

Questions about rename_room

What does the rename_room tool do? +

Rename a room in a map. It is categorised as a Write tool in the Loenn MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on rename_room? +

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

What risk level is rename_room? +

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

Can I rate-limit rename_room? +

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

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

rename_room is provided by the Loenn MCP server (magedeline/loenn-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.