Query WHOIS database for domain registration details. Returns registrant name, registrar, registration and expiration dates, registrant contact info, and nameserver list. Use for domain research, owner identification, or tracking registration status.
| Name | Required | Description | Default |
|---|---|---|---|
| domain | Yes | Domain name to look up in WHOIS (e.g. 'example.com', 'company.org') |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint and openWorldHint. The description adds details about returned fields but does not disclose potential limitations such as private registrations or rate limits. Reasonable but not exceptional.
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 two sentences, front-loaded with the key action and result, followed by usage context. No redundant information.
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 simple tool with one parameter and no output schema, the description covers purpose, return fields, and use cases. Could mention limitations or error cases, but sufficient for most agents.
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?
With 100% schema coverage, the schema already describes the domain parameter adequately. The tool description does not add new semantic information beyond the schema's example.
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 the tool queries WHOIS for domain registration details and lists the returned information, distinguishing it from sibling tools like check_dns or check_ssl which serve different purposes.
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 use cases like domain research and owner identification, implying when to use it. However, it does not explicitly exclude it from other scenarios or compare to siblings.
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 targets a distinct aspect of web analysis: DNS records, SSL certificates, full website crawling, technology stack detection, and WHOIS data. There is no ambiguity in their purposes.
All tool names follow a consistent verb_noun pattern: check_dns, check_ssl, crawl_website, detect_tech_stack, lookup_whois. The pattern is uniform and predictable.
5 tools is appropriate for a focused SEO and web analysis server. It covers the core areas without being excessive or too thin, though a couple more could be added.
Covers DNS, SSL, crawling, tech stack, and WHOIS, but misses common SEO tools like HTTP header inspection, robots.txt/sitemap analysis, or page speed evaluation. Notable gaps exist.