WHOIS/RDAP lookup

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

The description goes far beyond the hints by explaining the operational behavior: the specific data sources (IANA RDAP, rdap.org fallback), the safety profile (No auth, no side effects), and a critical policy detail (GDPR redaction), which is vital behavioral context.

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 text is dense but highly efficient, front-loading the core function and separating the functional description from the operational details (GDPR, data sources) and the routing advice, ensuring high information density without fluff.

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?

Given the complexity of integrating with external data sources and adhering to privacy standards (GDPR), the description provides every piece of necessary information. It covers use cases, output contents, safety, and alternative tools.

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?

Although schema coverage is 100%, the description adds significant semantic value by explicitly defining that the `query` parameter accepts *either* a domain name *or* an IPv4/IPv6 address. This clarifies expected input formats beyond the generic string type in 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 purpose is stated immediately as a 'Read-only WHOIS/RDAP lookup' and clearly delineates the scope: domains vs. IP addresses. It explicitly directs the user to a sibling tool, `lookup_dns`, if their goal is DNS record checking, making the differentiation perfect.

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 robust 'when-to-use' section (check ownership, age, vet suspicious domains) and a definitive 'when-not-to-use' clause (direct users to `lookup_dns` for DNS records). This eliminates ambiguity for the agent.

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