mail_send · Mailgent MCP Server MCP: Risk & Policy

WHAT IT DOES

What mail_send does on Mailgent MCP Server

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

WHY IT NEEDS A POLICY

Why mail_send needs a policy

mail_send creates and sends email messages, which is a write operation that modifies state (adds a message to recipient inboxes). While emails can theoretically be unsent or deleted, the primary action is irreversible once delivered.

From the tool's definition Tool description states 'Send an email from your agent' — this creates a new message and transmits it to recipients, a reversible write operation. The server manages email communications including 'sending' messages.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

mail_send Rate-limited

mail_send 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_send": {
      "limits": [
        {
          "counter": "mail_send_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 Mailgent MCP Server, so you can run agents against it safely.

FAQ

Questions about mail_send

What does the mail_send tool do? +

Send an email from your agent. It is categorised as a Write tool in the Mailgent 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 mail_send? +

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

What risk level is mail_send? +

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

Can I rate-limit mail_send? +

Yes. Add a rate_limit block to the mail_send 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_send completely? +

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

mail_send is provided by the Mailgent MCP Server MCP server (loomal-ai/loomal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.