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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds real domain context: how the score is computed (share of failed checks weighted by seriousness, 0% = no gaps, higher is worse), the exact label set, and the being_measured state where no price exists and purchase is blocked. It does not cover failure behavior for an unknown id.

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?

It is a single very long run-on sentence that front-loads the purpose before a dense field list. The field enumeration earns its place given there is no output schema, but the clause structure makes it harder to scan than it needs to be.

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?

With no output schema, the description carries the burden of explaining return values, and it does so thoroughly: score semantics, label enumeration, failed check names, measurement time, price, sale count and times, and page. The main gap is unspecified behavior when the id does not exist.

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 one parameter at 100% schema coverage, the baseline is 3. The description adds a concrete id example ('3f9a1c07b2e85d64') showing the expected format, which goes slightly beyond the schema, but it does not repeat or expand on the schema's note that ids come from search_website_gaps.

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 makes clear this is a single-site lookup by id returning an SEO gap score, and the enumerated fields (score, label, failed checks, price, sale history) separate it from the sibling search_website_gaps, which searches. It never uses a verb like 'returns' or 'retrieves', reading instead as a fragment, but the resource and scope are unambiguous.

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 explicit statement of when to use this versus search_website_gaps or search_problems, and no prerequisites or exclusions are given. The only usage-adjacent information is the being_measured case, which describes a return state rather than when to select the tool.

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