check_subdomain_takeoverLive scan of one domain: enumerate its subdomains (CT logs + DNS), then test each for dangling references on 13 cloud providers. Slow on large domains (up to a few minutes). Rate-limited per client.
| Name | Required | Description | Default |
|---|---|---|---|
| domain | Yes | The apex domain to scan |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Discloses that the scan is live, enumerates subdomains from CT logs and DNS, tests on 13 cloud providers, may take minutes on large domains, and is rate-limited per client. This adds meaningful behavioral context beyond the readOnlyHint and openWorldHint annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two concise sentences: the first states the process, the second mentions performance and rate-limit constraints. No filler, information is front-loaded, and every sentence earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description covers the scan process and performance constraints well, but lacks an output schema and does not describe the return format (e.g., list of vulnerable subdomains, report structure). This is a noticeable gap for a tool with no output schema.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema already fully describes the 'domain' parameter as 'The apex domain to scan' (100% coverage). The description adds only marginal context like 'one domain' and the scanning process, which doesn't materially enhance parameter understanding.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states a specific verb-resource-outcome: live scan of one domain, enumerate subdomains via CT logs and DNS, and test for dangling references on 13 cloud providers. This distinguishes it from siblings like check_email_auth and check_whois.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Provides clear context that it's a live scan of a single domain with caveats about slowness and rate limiting, implying when this tool is appropriate. However, it doesn't explicitly mention alternatives or when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a clearly distinct purpose: the three check_* tools target different failure modes (email auth, subdomain takeover, WHOIS), and the three base rate tools are distinguished by their roles (list catalog, search, get detail). No overlap or ambiguity.
Tool names follow a consistent verb_noun pattern (check_* and get/find/list), but there is a minor inconsistency: 'list_base_rates' uses plural while 'find_base_rate' and 'get_base_rate' use singular. Otherwise the naming is predictable.
Six tools is well-scoped for a specialized security scanner: three live checks and three data access functions. Each tool earns its place, and the count feels neither sparse nor bloated.
The tool set covers the full lifecycle of the stated purpose: live checks for three common failure types plus a complete knowledge base with list, search, and detail endpoints. No obvious gaps or dead ends.