Check Domain Availability

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

Annotations already indicate readOnly, idempotent, openWorld. Description adds value by detailing return fields (confidence, source, cache age) and handling of ambiguous results, which is beyond what annotations provide. No contradiction 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?

Two concise sentences front-load the purpose and usage, then add behavioral details. Every sentence is necessary and 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?

Given one required parameter and no output schema, the description covers purpose, return content, and edge cases (ambiguous lookups). However, it lacks details on domain format validation or limits, and the 0% schema coverage means the description could have provided more parameter guidance.

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 coverage is 0%, so description should compensate; it mentions 'one or more domains' but does not specify format (e.g., full domain names) or constraints. The parameter is simple (array of strings), so the minimal gain is acceptable, but no added detail.

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 checks domain availability, specifies the user intent ('when the user wants to know'), and distinguishes from siblings (check_usage, get_domain_info) by focusing on availability and return details like confidence and cache age.

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?

Explicitly says when to use ('when the user wants to know whether one or more domains are available to register'), but does not mention when not to use or provide explicit alternatives. However, sibling names imply differentiation.

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