undo_last_change · RPG Maker MZ MCP Server MCP

WHAT IT DOES

What undo_last_change does on RPG Maker MZ MCP Server

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

WHY IT NEEDS A POLICY

Why undo_last_change needs a policy

This tool modifies file state by reverting to a backup version. While it appears to undo changes rather than create new destructive effects, it still constitutes a write operation because it alters the current state of files. It is not Destructive because the original (current) file state could theoretically be re-applied or recovered from version history, and the operation itself is reversible.

From the tool's definition Tool description states it 'Restore[s] a file from its latest backup', which is a reversible modification operation that restores prior state rather than permanently deletes data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

undo_last_change Rate-limited

undo_last_change 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": {
    "undo_last_change": {
      "limits": [
        {
          "counter": "undo_last_change_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 RPG Maker MZ MCP Server, so you can run agents against it safely.

FAQ

Questions about undo_last_change

What does the undo_last_change tool do? +

Restore a file from its latest backup. If filename is not specified, restores the most recently modified file. It is categorised as a Write tool in the RPG Maker MZ 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 undo_last_change? +

Register the RPG Maker MZ MCP Server MCP server in PolicyLayer and add a rule for undo_last_change: 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 RPG Maker MZ MCP Server. Nothing to install.

What risk level is undo_last_change? +

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

Can I rate-limit undo_last_change? +

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

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

undo_last_change is provided by the RPG Maker MZ MCP Server MCP server (rein1225/rpgmakermz_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.