mail_archive · Hermes Google MCP: Risk & Policy

WHAT IT DOES

What mail_archive does on Hermes Google

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

WHY IT NEEDS A POLICY

Why mail_archive needs a policy

Archiving is a reversible modification of data (the message itself remains intact, only its label status changes). It does not read-only retrieve data (Read), execute arbitrary code (Execute), permanently delete data (Destructive), nor involve financial transactions (Financial).

From the tool's definition "Archive a message in Hermes's inbox (removes the INBOX label)" – this modifies email metadata by removing a label, which is a write operation that changes the organizational state of a message.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

mail_archive Rate-limited

mail_archive 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_archive": {
      "limits": [
        {
          "counter": "mail_archive_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 Hermes Google, so you can run agents against it safely.

FAQ

Questions about mail_archive

What does the mail_archive tool do? +

Archive a message in Hermes's inbox (removes the INBOX label). It is categorised as a Write tool in the Hermes Google 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_archive? +

Register the Hermes Google MCP server in PolicyLayer and add a rule for mail_archive: 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 Hermes Google. Nothing to install.

What risk level is mail_archive? +

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

Can I rate-limit mail_archive? +

Yes. Add a rate_limit block to the mail_archive 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_archive completely? +

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

mail_archive is provided by the Hermes Google MCP server (jimmy-larsson/hermes-google). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.