domain_age

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

With no annotations, the description must disclose behavioral traits. It uses the word 'estimate', implying approximation, but does not explain data sources, accuracy, or possible side effects. It lacks details on network requirements or what happens with unregistered domains.

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 extremely concise: one sentence for purpose followed by a parameter list with example. Every word serves a purpose, no fluff. Front-loaded with the core action.

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 tool's low complexity (one parameter, no annotations, output schema present), the description is mostly complete. It states the purpose and parameter usage. However, it could mention error handling or limitations (e.g., 'requires valid registered domain') to fully prepare the agent.

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 input schema provides no parameter descriptions (coverage 0%). The description compensates by specifying the parameter 'domain' with an example ('e.g. example.com'), adding clear meaning beyond the raw schema. This effectively guides the user on input format.

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 estimates 'domain registration age and expiry information', providing a specific verb and resource. It distinguishes from siblings like dns_lookup or dns_whois_lookup by focusing on age/expiry rather than general DNS data. However, it could be slightly more precise (e.g., 'expiry information' is vague).

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?

No guidance is given on when to use this tool versus alternatives. For instance, it doesn't mention that one should use domain_age for age/expiry vs dns_whois_lookup for full whois data. Users receive no context for selection.

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