search_term_popularity

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

Annotations already declare readOnlyHint=true, idempotentHint=true and openWorldHint=true, so the safety profile is known without the description. The description adds nothing beyond that: no statement about what the popularity metric means (volume? rank? impression share?), whether time ranges are required, or how pagination affects results. It repeats the title rather than extending it.

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?

A single four-word sentence is front-loaded with zero waste, but at this length the brevity is under-specification rather than economy. There is nothing extraneous, but there is also almost nothing there to structure.

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 an output schema present and full parameter coverage, the description technically needn't explain return values. But a 9-parameter, open-world search-term analytics tool that is nearly indistinguishable from sibling search_term_report needs at least a sentence on what insight it yields and how it differs. The definition does not supply that.

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% across all 9 parameters, so the schema itself documents fields, filters, groupBy, sorting, timeRange and pagination. The description adds no semantic layer on top — for a popularity query, an explanation of which fields/groupBy values matter would have been valuable — so 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?

States a verb ("Read") and a resource ("search-term popularity insights"), so the basic operation is identifiable. But "insights" is vague about what is actually returned, and the description does nothing to separate this tool from the closely-named sibling search_term_report (or keyword_report, impression_share), which likely also surface search-term data.

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 when-to-use guidance, no mention of prerequisites (profile + adAccountId, which the schema marks required), and no routing to alternatives. When an agent has to choose between search_term_popularity and search_term_report, nothing in the text helps.

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