gmail_update_label · Mcp Gmail MCP: Risk & Policy

WHAT IT DOES

What gmail_update_label does on Mcp Gmail

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

WHY IT NEEDS A POLICY

Why gmail_update_label needs a policy

The tool modifies Gmail labels, which are reversible organizational metadata (labels can be recreated or restored). This is a Write operation rather than Destructive since label updates do not permanently erase data. Severity is high because unauthorized label manipulation could affect email organization, visibility, and filtering for the account owner, potentially causing operational disruption or privacy concerns.

From the tool's definition Tool name 'gmail_update_label' indicates modification of Gmail label metadata. The server is described as 'Gmail MCP server with auto authentication support', confirming this tool operates on Gmail data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

gmail_update_label Rate-limited

gmail_update_label 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": {
    "gmail_update_label": {
      "limits": [
        {
          "counter": "gmail_update_label_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 Mcp Gmail, so you can run agents against it safely.

FAQ

Questions about gmail_update_label

What does the gmail_update_label tool do? +

gmail_update_label. It is categorised as a Write tool in the Mcp Gmail MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on gmail_update_label? +

Register the Mcp Gmail MCP server in PolicyLayer and add a rule for gmail_update_label: 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 Mcp Gmail. Nothing to install.

What risk level is gmail_update_label? +

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

Can I rate-limit gmail_update_label? +

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

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

gmail_update_label is provided by the Mcp Gmail MCP server (@monsoft/mcp-gmail). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.