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 one useful behavioral note — the historical behavior change from sitemaps — but says nothing about default row counts, time-window defaults, or data freshness, which matter for a metrics tool.

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 sentences, zero filler, with the core purpose front-loaded and the disambiguation parenthetical placed after it. Every clause earns its place.

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 usefully enumerates the returned fields (clicks, impressions, CTR, position per query). It is nearly complete for a simple two-param read tool, missing only scoping details such as the default date range of the GSC performance data.

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% with only two parameters, and the limit parameter's ordering ('highest clicks first') is already documented in the schema. The description adds no parameter meaning beyond that, so the baseline 3 applies.

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?

Names a specific verb+resource ('top QUERIES by Search Console performance for a site') and enumerates the returned metrics (clicks, impressions, CTR, position). It also explicitly disambiguates from sibling get_gsc_sitemaps, so an agent can separate the two without opening either schema.

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?

Explicitly routes the sitemap use case to get_gsc_sitemaps, which is a genuine when-not statement. However it gives no guidance relative to the other GSC siblings (get_gsc_pages, get_gsc_metrics, get_gsc_keyword_candidates), leaving the broader selection context to inference.

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