gmail_send_email · Gmail MCP Server MCP: Risk & Policy

WHAT IT DOES

What gmail_send_email does on Gmail MCP Server

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

WHY IT NEEDS A POLICY

Why gmail_send_email needs a policy

This tool creates new email messages or modifies existing threads by adding replies—both reversible Write operations. It does not execute arbitrary code (Execute), delete/destroy data (Destructive), or transfer funds (Financial).

From the tool's definition Tool description states 'Send an email. Can send new emails or reply to existing threads.' The verb 'send' and explicit mention of composing and dispatching emails indicates data creation/modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

gmail_send_email Rate-limited

gmail_send_email 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_send_email": {
      "limits": [
        {
          "counter": "gmail_send_email_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 Gmail MCP Server, so you can run agents against it safely.

FAQ

Questions about gmail_send_email

What does the gmail_send_email tool do? +

Send an email. Can send new emails or reply to existing threads. Requires confirmation before sending. It is categorised as a Write tool in the Gmail 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 gmail_send_email? +

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

What risk level is gmail_send_email? +

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

Can I rate-limit gmail_send_email? +

Yes. Add a rate_limit block to the gmail_send_email 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_send_email completely? +

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

gmail_send_email is provided by the Gmail MCP Server MCP server (murphy360/mcp_gmail). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.