update_send_as · Gmail MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_send_as does on Gmail MCP Server

AI agents use update_send_as 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 update_send_as needs a policy

This tool modifies existing email alias settings reversibly through Gmail's API. It qualifies as Write rather than Execute because it updates configuration data (an email alias) rather than triggering external operations or executing arbitrary code.

From the tool's definition Updates a send-as alias in Gmail, modifying email identity configuration without deletion or creation of new aliases.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_send_as Rate-limited

update_send_as 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": {
    "update_send_as": {
      "limits": [
        {
          "counter": "update_send_as_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 update_send_as

What does the update_send_as tool do? +

Updates a send-as alias. 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 update_send_as? +

Register the Gmail MCP Server MCP server in PolicyLayer and add a rule for update_send_as: 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 update_send_as? +

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

Can I rate-limit update_send_as? +

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

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

update_send_as is provided by the Gmail MCP Server MCP server (nk900600/gmail-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.