patch_send_as · Gmail MCP Server MCP: Risk & Policy

WHAT IT DOES

What patch_send_as does on Gmail MCP Server

AI agents use patch_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 patch_send_as needs a policy

This tool modifies email sending aliases reversibly—a user can update the patch with different values or delete the alias. It does not irreversibly delete data (Destructive), does not execute arbitrary code (Execute), does not move money (Financial), and does not merely read data (Read).

From the tool's definition Tool name 'patch_send_as' and description 'Patches the specified send-as alias' indicate modification of existing email sending configuration. 'Patch' is a standard HTTP operation for partial updates of resources.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

patch_send_as Rate-limited

patch_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": {
    "patch_send_as": {
      "limits": [
        {
          "counter": "patch_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 patch_send_as

What does the patch_send_as tool do? +

Patches the specified 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 patch_send_as? +

Register the Gmail MCP Server MCP server in PolicyLayer and add a rule for patch_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 patch_send_as? +

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

Can I rate-limit patch_send_as? +

Yes. Add a rate_limit block to the patch_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 patch_send_as completely? +

Set action: deny in the PolicyLayer policy for patch_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 patch_send_as? +

patch_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.