redo · Melo MCP: Risk & Policy

WHAT IT DOES

What redo does on Melo

AI agents invoke redo to trigger actions in Melo. 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 redo needs a policy

This tool executes commands that alter the state of Roblox Studio by replaying up to 50 previously undone operations. While redo is technically reversible (via undo), the tool actively triggers Studio actions whose effects depend on the count argument and the prior operation history.

From the tool's definition The tool description states 'Trigger redo in Studio to redo the last N operations.' The verb 'trigger' combined with the action to 'redo the last N operations' indicates this executes state changes within Roblox Studio.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

redo Rate-limited

redo 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": {
    "redo": {
      "limits": [
        {
          "counter": "redo_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 Melo, so you can run agents against it safely.

FAQ

Questions about redo

What does the redo tool do? +

Trigger redo in Studio to redo the last N operations. Args: - count (number, optional): Number of redo steps (default: 1, max: 50) Returns: Confirmation of redo. It is categorised as a Execute tool in the Melo MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on redo? +

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

What risk level is redo? +

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

Can I rate-limit redo? +

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

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

redo is provided by the Melo MCP server (yannyhl/linkedsword-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.