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

Annotations only declare readOnlyHint and openWorldHint. The description adds substantial behavioral detail: the returned fields, the not_found error path, price_on_request semantics with an explicit 'never imply a price' rule, and available_for_purchase=false meaning the listing is sold and purchase_url is unusable. It remains consistent with readOnlyHint.

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 longer than typical, but the length is earned: the purpose sentence is front-loaded, the return summary is compact, and the two IMPORTANT caveats address high-stakes edge cases. Minor redundancy exists with 'Present price, key attributes, and the purchase link' repeating the return list, but overall it remains well organized.

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 a single-parameter schema, read-only annotation, and output schema present, the description covers invocation context, error handling, and edge-case behavior. Nothing an agent needs to decide whether to call this tool or to interpret special price/availability results is missing.

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% and the only parameter domain is already described as 'The domain to look up, including extension.' The description reinforces the single-domain scope but adds no new parameter format, constraints, or examples beyond the schema, so the baseline 3 is appropriate.

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?

Description uses a specific verb+resource: 'Get the full detail record for ONE specific Atom domain listing.' It explicitly positions itself as the deep-dive after search_brandable_domains or generate_domain_names, and contrasts with check_domain_availability for non-Atom domains, clearly distinguishing it from siblings.

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?

Gives explicit when-to-use guidance: after a user picks a name from search_brandable_domains or generate_domain_names, or asks to know more about a particular domain. Also gives an exclusion: if the domain is not an Atom listing, it returns not_found and the agent should use check_domain_availability. This is strong routing guidance.

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