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. Beyond that the description adds only the row shape (four metrics); it says nothing about GSC data lag, default date range, default limit or result caps — context that materially affects how an agent interprets numbers. That is modest added value above the annotations, hence a 3.

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?

Two tight sentences, front-loaded with what the rows contain before the filter/sort list, with no filler. The semicolon-separated capability clause is dense but reads cleanly; minor terseness is the only knock.

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 14 optional parameters, no output schema and no required fields, the description should establish the defaults an agent must know (default date range, default limit, default search_type) and where this sits relative to other GSC reports. It covers the returned fields but not the defaults or the sibling boundary, so it is adequate rather than complete.

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 71%, so the schema does most of the work and the baseline is 3. The description enumerates a subset of the filter parameters (page, query text, country, device) and omits site, folder, date range, search_type, language and detail, and its sort list drops 'ctr' even though the schema enum includes it — so it neither fully compensates nor adds meaning beyond the 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 uses a specific resource ('search queries (keywords) the site appears for') and names the metrics returned (clicks, impressions, CTR, position), so the agent knows this is a query-level GSC report rather than a page-level one. It stops short of naming how it differs from close siblings like gsc_breakdown, gsc_pages or gsc_performance, leaving that distinction to inference.

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 second sentence lists filtering and sorting capabilities, which is capability disclosure, not usage guidance. There is no statement of when to pick this tool over gsc_breakdown, gsc_pages or gsc_performance, and no note on prerequisites such as needing a site when multiple are enabled.

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