test_domain_smtp · TrekMail MCP Server MCP: Risk & Policy

WHAT IT DOES

What test_domain_smtp does on TrekMail MCP Server

AI agents invoke test_domain_smtp to trigger actions in TrekMail MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why test_domain_smtp needs a policy

The tool name indicates it performs an SMTP test against a domain, which involves executing an external network operation (connecting to a remote SMTP server). This is not a passive read but an active probe that triggers real network connections. The description is minimal ('Test a domain'), so confidence is moderate, but the SMTP context strongly implies execution of an external operation.

From the tool's definition 'Test a domain' and 'test_domain_smtp' — triggers an active SMTP connection/probe against a domain's mail server

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

test_domain_smtp Rate-limited

test_domain_smtp stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "test_domain_smtp": {
      "limits": [
        {
          "counter": "test_domain_smtp_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches TrekMail MCP Server, so you can run agents against it safely.

FAQ

Questions about test_domain_smtp

What does the test_domain_smtp tool do? +

Test a domain. It is categorised as a Execute tool in the TrekMail MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on test_domain_smtp? +

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

What risk level is test_domain_smtp? +

test_domain_smtp is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit test_domain_smtp? +

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

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

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