Reverse WHOIS Search

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint, destructiveHint, idempotentHint, and openWorldHint. The description adds minimal behavioral context beyond mentioning the data source (WhoisXML). No contradictions with 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?

A single, front-loaded sentence with the verb 'Find' immediately conveys the action. Every word earns its place; no 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 simple tool with one parameter, complete annotations, and an output schema, the description adequately covers purpose, usage context, and source. Minor gap: no mention of result volume or pagination.

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 single 'keyword' parameter has 100% schema coverage with a clear description. The tool description reiterates acceptable keyword types (person, company, email) but adds no new semantics beyond the schema.

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 it finds domains registered by a person, company, or email, specifying it's a reverse WHOIS lookup for OSINT and brand monitoring. This differentiates it from sibling tools like whois.domain.lookup and whois.domain.availability.

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 context for use (OSINT, brand monitoring) and implies the tool is for reverse lookups, but does not explicitly state when not to use it or compare with alternatives among siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.