domain_check

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

No annotations are present, so the description carries the behavioral disclosure burden. The explicit 'Read-only' label is valuable and discloses that the operation has no side effects. However, it does not mention response format, rate limits, authentication needs, or edge cases such as invalid domain formats or unsupported TLDs.

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 a single, tightly written sentence with no filler. The core operation is front-loaded, and each clause contributes something useful: the action, the resource, the possible outcomes, and the read-only safety note.

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 one-parameter, read-only tool with no output schema and no annotations, the description covers the main semantics and the outcome categories well. It does not describe the exact return shape or provide input format examples, but the simplicity of the tool makes those omissions relatively minor.

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 schema provides only the parameter name and type, with 0% schema description coverage. The description compensates by clarifying that the domains parameter is a list of domain names to be checked and by indicating the possible status outcomes. It does not specify accepted domain syntax or normalization rules, but it adds meaningful semantics beyond the bare array-of-strings 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 uses a specific verb ('Availability check') and resource ('domains'), and enumerates the result categories: registered elsewhere, free, or transferable. This distinguishes it clearly from sibling tools like domain_list or domain_info, which are about managing or viewing domains that are already known.

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 explicit when-to-use or when-not-to-use guidance is provided. The description implies this tool is for checking domain availability rather than managing owned domains, but it never names alternatives or explains the conditions for choosing domain_check over domain_info, domain_list, or domain_price.

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