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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds nothing beyond that: it does not say what is returned, how the internal auto-pagination implied by needCount behaves, whether results are capped at 10 ASINs, or anything about rate/credit costs for an external data provider.

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 single sentence is short but is a title restatement rather than a compressed explanation, so there is no front-loaded information payload. Brevity here reflects under-specification, not economy.

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 13-parameter research API with no output schema, the description provides no information about inputs, filters, return shape, or pagination. It is completely inadequate for a tool of this complexity; an agent would have to reconstruct intent from the schema and name alone.

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 description coverage is 100%, so all 13 parameters (marketplace enum values, ASIN list cap, word-count and search-volume ranges, include variants, sorting) are already documented in the schema. The description adds no parameter meaning at all, which lands at the baseline of 3 for a fully documented 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 is essentially a restatement of the tool name and title: 'keywords/by asin API' adds no verb or scope beyond what 'nexscope_data_js_keywords_by_asin' already encodes. It does not distinguish this tool from the many close siblings that also return keywords for ASINs (nexscope_amazon_asin_keywords, nexscope_data_sf_asin_keywords, nexscope_data_js_keywords_by_keyword), so an agent cannot tell which one to pick from the text alone.

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?

There is no guidance about when to use this tool versus alternatives, no prerequisites (e.g., marketplace availability, ASIN validity), and no mention of when not to use it. The agent is left to infer everything from the name.

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