AI agents call subdomain to retrieve information from ThreatMCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool only retrieves/queries subdomain records associated with a domain. It performs a read-only lookup against threat intelligence data with no write or execution side effects. Severity is medium because subdomain enumeration can be used for reconnaissance and attack surface mapping, but the tool itself causes no direct harm.
From the tool's definition 子域名查询：获取域名的所有子域名信息，用于资产发现和安全评估 — 'query' and 'get' semantics; retrieves subdomain information for asset discovery and security assessment
Documented attack patterns abuse exactly the kind of access subdomain gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and ThreatMCP, and nothing reaches the server without passing your rules. This is the rule we recommend for subdomain:
{
"version": "1",
"default": "deny",
"tools": {
"subdomain": {}
}
}subdomain is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
子域名查询：获取域名的所有子域名信息，用于资产发现和安全评估. It is categorised as a Read tool in the ThreatMCP MCP Server, which means it retrieves data without modifying state.
Register the Threat MCP server in PolicyLayer and add a rule for subdomain: 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 ThreatMCP. Nothing to install.
subdomain is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the subdomain 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.
Set action: deny in the PolicyLayer policy for subdomain. 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.
subdomain is provided by the Threat MCP server (naxg/threatmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from ThreatMCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
15 ThreatMCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.