check_whoisLive WHOIS lookup for up to 100 domains: expiry date, registrar, nameservers. Use to catch registrations about to lapse. Rate-limited per client.
| Name | Required | Description | Default |
|---|---|---|---|
| domains | Yes | Domains to look up (1-100). Array preferred; a JSON-encoded array or comma/space-separated string also works. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the operation as read-only (readOnlyHint=true, openWorldHint=true), lowering the bar. The description adds valuable behavioral details beyond annotations: 'Live', 'up to 100 domains', and 'Rate-limited per client'. It does not disclose potential failure modes or response structure, but for a read-only lookup this is acceptable.
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?
The description is compact (two sentences) and front-loaded with the primary action and result. Each clause adds meaning: 'Live' signals immediacy, the domain limit is stated, the purpose (catching lapses) is included, and the rate limit is disclosed. No filler or redundancy.
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?
For a single-parameter read-only tool with no output schema, the description covers the essential operation, constraints (100 domains, rate limit), and a practical use case. It could optionally mention error behavior or that results are per-domain, but the information provided is sufficient for an agent to select and invoke the tool correctly.
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?
Schema description coverage is 100%, and the parameter 'domains' already includes details about accepted formats and the 1-100 count. The tool description does not add significant parameter semantics beyond the schema, so the baseline score of 3 is appropriate.
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 uses a specific verb ('live WHOIS lookup') and names the resource (domains) and key outputs (expiry date, registrar, nameservers). It clearly distinguishes from siblings like check_email_auth and check_subdomain_takeover, which address different concerns.
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?
The description provides a concrete use case ('Use to catch registrations about to lapse') and contextualizes when the tool is appropriate. It does not explicitly name alternatives or exclusions, but the sibling tools are contextually distinct, and the intended scenario is clear.
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.