Check domain availability

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

The description adds valuable behavioral context beyond the annotations: it mentions the return of price in micro-units of the returned currency and explicitly notes that the answer may not be definitive, which relates to the FAST vs FULL distinction. The readOnlyHint and openWorldHint annotations are consistent and complemented by this added nuance.

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, focused sentence that front-loads the core purpose and appends essential return-value details. It is concise with no filler, earning a high score for efficiency.

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 simple tool scope, presence of an output schema, and annotations covering safety and open-world behavior, the description provides sufficient information: what it does, what it returns, and key unit caveats. No critical gaps for an agent to invoke it correctly.

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 already provides full parameter descriptions for both 'domain' and 'check_type' (including the FAST/FULL enum values). The description does not add new parameter-level semantics beyond what the schema offers, so it meets the baseline but does not exceed it.

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 ('Check whether') and identifies the resource ('a domain is available to register'), clearly distinguishing it from sibling DNS management tools. It states the primary function in a single, unambiguous sentence.

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 purpose makes the primary use case obvious, but the description provides no explicit guidance on when to choose this tool over alternatives or when to prefer FAST vs FULL. The schema describes the check_type options, but the description itself does not elaborate on usage context.

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