check_domain_availability

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

No annotations exist, so description carries full burden. It describes the operation as a 'WHOIS availability lookup' implying read-only, but doesn't disclose any side effects, error behavior, or expected return format. Minimal beyond basic operation.

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 sentences, no unnecessary words. First sentence establishes purpose and method, second provides example and usage advice. Perfectly front-loaded and efficient.

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 one-parameter tool without output schema, the description covers purpose, usage context, and example. However, it omits what the return value will be (boolean? availability status?), leaving the agent partially informed.

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 100% with description for the only parameter. The description adds 'Pass the full domain' reinforcing the format, but this is already in the schema. No additional semantics beyond what the schema provides.

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 specific verb 'Check' and resource 'domain name availability' with context 'pre-purchase WHOIS availability lookup'. It differentiates from domain sibling tools (list_domains, get_domain, register_domain) by focusing on availability checking.

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 explicitly advises when to use: 'Use before quoting a registration or suggesting an alternative name.' This provides clear context and workflow integration. It lacks explicit 'when not to use' but the purpose is well-scoped.

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