add_trigger · Loenn MCP: Risk & Policy

WHAT IT DOES

What add_trigger does on Loenn

AI agents use add_trigger 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 add_trigger needs a policy

This tool creates a new trigger object in a Celeste map file, which is a reversible modification (triggers can be edited or removed). It does not delete or execute external operations, placing it in the Write category. Severity is medium because incorrect trigger placement could affect map playability, but changes are editable.

From the tool's definition Tool name 'add_trigger' combined with server description stating it 'enables AI agents to read, edit, analyze, procedurally generate, and preview Celeste .bin map files'. The 'add_' prefix indicates creation/modification of map data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_trigger Rate-limited

add_trigger 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": {
    "add_trigger": {
      "limits": [
        {
          "counter": "add_trigger_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 add_trigger

What does the add_trigger tool do? +

add_trigger. 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 add_trigger? +

Register the Loenn MCP server in PolicyLayer and add a rule for add_trigger: 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 add_trigger? +

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

Can I rate-limit add_trigger? +

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

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

add_trigger 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.