move_to_folder · Nexus Core MCP: Risk & Policy

WHAT IT DOES

What move_to_folder does on Nexus Core

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

WHY IT NEEDS A POLICY

Why move_to_folder needs a policy

The tool performs reversible write operations on Gmail message metadata (labels and inbox status) rather than reading, executing external code, destructively deleting, or moving money. An AI agent could misuse this by reorganizing messages into wrong folders, but the operations are undoable. Severity is medium because unintended bulk reorganization of messages could cause user confusion but no permanent data loss.

From the tool's definition Tool description states 'Move = apply label + remove INBOX', indicating it modifies Gmail labels and message state. The operations (applying labels, removing INBOX) are reversible data modifications.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

move_to_folder Rate-limited

move_to_folder 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": {
    "move_to_folder": {
      "limits": [
        {
          "counter": "move_to_folder_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 Nexus Core, so you can run agents against it safely.

FAQ

Questions about move_to_folder

What does the move_to_folder tool do? +

Move = apply label + remove INBOX. Gmail has no real folders; labels stand in. It is categorised as a Write tool in the Nexus Core MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on move_to_folder? +

Register the Nexus Core MCP server in PolicyLayer and add a rule for move_to_folder: 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 Nexus Core. Nothing to install.

What risk level is move_to_folder? +

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

Can I rate-limit move_to_folder? +

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

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

move_to_folder is provided by the Nexus Core MCP server (noumenon-ai/nexus-core). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.