domains_checkDomainAvailabilityV1

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

With no annotations, the description must disclose behavioral traits. It mentions the rate limit (90 req/min) and TLD format rule (no leading dot). Although it doesn't explicitly state read-only, the phrase 'verify availability' implies non-destructive behavior. It could add a note that it does not purchase, but that's inferred.

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 concise and well-structured, with distinct lines for main purpose, usage, and constraints. Each sentence adds information with no redundancy. It is front-loaded with the primary function.

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?

While covering purpose, usage, rate limit, and parameter semantics, it does not describe the response format or what availability statuses look like. However, for a straightforward check tool with no output schema, it is sufficiently complete. The rate limit and alternative domain guidance add robustness.

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%, so baseline is 3. The description adds semantics beyond the schema by explaining the relationship between tlds and with_alternatives (must supply only one TLD) and reinforces the TLD format. This adds value over the schema alone.

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 across multiple TLDs, using a specific verb ('Check') and resource ('domain names'), and distinguishes it from sibling tools like domain suggestion or purchase tools. It also includes the explicit use case 'verify domain availability before purchase.'

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 gives explicit when-to-use guidance: 'Use this endpoint to verify domain availability before purchase.' It also provides specific usage conditions for alternatives (one TLD with with_alternatives=true) and TLD formatting rules, which effectively directs the agent.

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