Discover subdomains using passive methods: Certificate Transparency logs + DNS brute-force (no active probing). Use to map organization's attack surface; non-intrusive. Response carries next_calls — capped at 5 ssl_check hints (one per first-five subdomain) so triage scales to large enumerations ...
Single-target operation
Part of the ContrastAPI MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents call subdomain_enum to retrieve information from ContrastAPI without modifying any data. This is common in research, monitoring, and reporting workflows where the agent needs context before taking action. Because read operations don't change state, they are generally safe to allow without restrictions -- but you may still want rate limits to control API costs.
Even though subdomain_enum only reads data, uncontrolled read access can leak sensitive information or rack up API costs. An agent caught in a retry loop could make thousands of calls per minute. A rate limit gives you a safety net without blocking legitimate use.
Read-only tools are safe to allow by default. No rate limit needed unless you want to control costs.
tools:
subdomain_enum:
rules:
- action: allowSee the full ContrastAPI policy for all 53 tools.
Agents calling read-class tools like subdomain_enum have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Read risk category across the catalogue. The same policy patterns (rate-limit, allow) apply to each.
Discover subdomains using passive methods: Certificate Transparency logs + DNS brute-force (no active probing). Use to map organization's attack surface; non-intrusive. Response carries next_calls — capped at 5 ssl_check hints (one per first-five subdomain) so triage scales to large enumerations without token bloat; pull tail entries by name when needed. Free: 30/hr, Pro: 500/hr. Returns {domain, count, subdomains, sources, found_via_wordlist, found_via_crtsh, crtsh_status, warnings, summary, next_calls}. Always check crtsh_status: 'ok' means the CT lookup completed (so a low count is real); 'timeout' / 'rate_limited' / 'unavailable' / 'error' means CT logs did not respond and the count is wordlist-only — the actual attack surface is likely larger, retry later or surface the limitation to the user.. It is categorised as a Read tool in the ContrastAPI MCP Server, which means it retrieves data without modifying state.
Add a rule in your Intercept YAML policy under the tools section for subdomain_enum. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the ContrastAPI MCP server.
subdomain_enum 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_enum rule in your Intercept 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 Intercept policy for subdomain_enum. 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_enum is provided by the ContrastAPI MCP server (contrastcyber/contrastapi). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic policy on every MCP tool call. Per-identity grants. Full audit log.