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

Annotations already declare readOnlyHint, openWorldHint, and destructiveHint=false, so the safety burden is low. The description adds that results can be grouped, filtered, and compared to the previous period, but does not disclose output shape, pagination/limits behavior, or data-lag nuances beyond what the input schema already documents.

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 description is two compact sentences with no filler. It front-loads the core purpose and then enumerates the distinguishing capabilities in a scannable list. Every phrase 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?

The input schema is rich and fully descriptive, covering all 8 parameters, defaults, and constraints. The description covers the core operations well. The only notable gap is that there is no output schema and the description does not explicitly state the returned metric set, though the sort_by enum strongly implies clicks, impressions, CTR, and position.

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 the schema carries the parameter documentation burden. The description's mention of grouping, filtering, and previous-period comparison maps to group_by, filter_page/filter_query, and compare_previous, but adds no semantics beyond the already-detailed 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 states a specific verb/resource: a flexible Google Search Console query over performance data, and summarizes the grouping, filtering, and comparison capabilities. It is clearly distinct from obvious siblings like list_sites or bing_performance, though it does not explicitly name a sibling or differentiate itself from traffic_history/site_overview.

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 description implies usage: use this when you need a customizable query with grouping, filters, or period comparison. However, there is no explicit when-to-use versus alternative tools guidance, no exclusions, and no reference to sibling tools like bing_performance or traffic_history for simpler or different cases.

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