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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety is covered. The description adds genuinely useful operational context beyond the annotations: a prerequisite (Google Search Console must be connected), where to connect it, and multi-account property resolution behavior.

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?

Front-loads the core definition, then rationale, then prerequisites. Five sentences is slightly more than needed and the ROI rationale is arguably optional, but nothing is repetitive and the setup instructions earn their 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?

For a read-only analytical tool with fully documented parameters and no output schema, the description covers purpose, prerequisites, and account-resolution behavior. It could say more about the shape of results (query, impressions, CTR), but the core call path is 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 description coverage is 100% and each parameter (site, maxCtr, minImpressions, rowLimit, dates) is documented in the schema with defaults and formats. The description adds no parameter-level detail, 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?

Specific verb+resource (queries with high impressions but low CTR) with an explicit diagnostic framing that separates it from siblings like get_gsc_low_ctr_pages and get_gsc_opportunity_queries. An agent can tell what this returns without opening the 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?

Gives clear context for when this is the right analysis (ranking but not clicked, weak title/meta) and even prioritization guidance ('higher ROI than chasing new rankings'). It does not, however, explicitly name which sibling to use instead when the agent wants pages-level or broader opportunity data.

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