setup_dmarc · Domain Suite MCP: Risk & Policy

WHAT IT DOES

What setup_dmarc does on Domain Suite

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

WHY IT NEEDS A POLICY

Why setup_dmarc needs a policy

This tool creates a new DNS TXT record for DMARC policy. While DNS modifications are reversible (can be deleted or updated), this is a Write category action that modifies domain authentication infrastructure.

From the tool's definition Tool adds/creates a DMARC policy TXT record via DNS, which is a write operation that modifies domain configuration. Description uses "Add" indicating creation/modification of DNS records.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

setup_dmarc Rate-limited

setup_dmarc 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": {
    "setup_dmarc": {
      "limits": [
        {
          "counter": "setup_dmarc_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 Domain Suite, so you can run agents against it safely.

FAQ

Questions about setup_dmarc

What does the setup_dmarc tool do? +

Add DMARC policy TXT record. It is categorised as a Write tool in the Domain Suite MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on setup_dmarc? +

Register the Domain Suite MCP server in PolicyLayer and add a rule for setup_dmarc: 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 Domain Suite. Nothing to install.

What risk level is setup_dmarc? +

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

Can I rate-limit setup_dmarc? +

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

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

setup_dmarc is provided by the Domain Suite MCP server (oso95/domain-suite-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.