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

Annotations already declare the operation read-only and idempotent, and the description adds a surprising array-of-arrays response grouping, a 1–3 monthly-bucket date restriction, and a billing rule that counts rows across all groups. These are exactly the kind of non-obvious behaviors an agent needs before invoking.

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 two substantive sentences are dense and valuable, but the opening 'Website Keywords' is a tautological filler that occupies the front-loaded position. It should have been replaced with an actual action statement.

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 100% schema coverage, an output schema, and safety-focused annotations, the description covers the remaining non-obvious contract details: date-range span, response grouping, and billing. Nothing needed to call the tool correctly appears missing, though the absent purpose statement lowers the overall completeness.

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?

With 100% schema description coverage, the baseline is met. The description goes beyond the schema by constraining the start_date/end_date span to 1–3 monthly buckets, which cannot be inferred from any individual parameter description.

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 opening phrase 'Website Keywords' simply restates the title and implies an action only through the tool name. The rest of the description covers response shape and date constraints, not what the tool actually retrieves. It also does not differentiate it from the sibling get_similarweb_keyword_competitors.

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 guidance is given about when to choose this tool over alternatives such as get_similarweb_keyword_competitors or other SimilarWeb siblings. The date constraint is a precondition for a valid call, not a usage rule.

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