mail_update_labels · Mailgent MCP Server MCP: Risk & Policy

WHAT IT DOES

What mail_update_labels does on Mailgent MCP Server

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

WHY IT NEEDS A POLICY

Why mail_update_labels needs a policy

This tool creates or modifies message labels, which are metadata tags that organize emails. Label changes are reversible—labels can be added and removed without permanently deleting or destroying data. While modifying labels could affect email organization and filtering workflows, the operation is non-destructive and typically low-impact.

From the tool's definition Tool name 'mail_update_labels' and description 'Add or remove labels on a message' indicate reversible modification of message metadata through label operations (add/remove).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

mail_update_labels Rate-limited

mail_update_labels 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": {
    "mail_update_labels": {
      "limits": [
        {
          "counter": "mail_update_labels_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 Mailgent MCP Server, so you can run agents against it safely.

FAQ

Questions about mail_update_labels

What does the mail_update_labels tool do? +

Add or remove labels on a message. It is categorised as a Write tool in the Mailgent 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 mail_update_labels? +

Register the Mailgent MCP Server MCP server in PolicyLayer and add a rule for mail_update_labels: 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 Mailgent MCP Server. Nothing to install.

What risk level is mail_update_labels? +

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

Can I rate-limit mail_update_labels? +

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

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

mail_update_labels is provided by the Mailgent MCP Server MCP server (loomal-ai/loomal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.