ad_group_report

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. Beyond that the description adds only the vague adjective 'bounded', which is never explained (page-size cap? row limits? date bounds?). It says nothing about rate limits, data freshness, or what happens when the window is exceeded.

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 clause with no filler, so it is certainly concise. But it is compressed past usefulness — 'bounded' and 'rows' are the only content beyond the name, which reads as under-specification rather than disciplined brevity.

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?

An output schema exists, so return values need not be explained, and the schema covers parameters fully. However, for a 9-parameter reporting tool sitting among several sibling report tools, the definition leaves the agent without the routing and report-shape context needed to invoke it confidently.

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 every one of the 9 parameters (fields, filters, groupBy, sorting, timeRange, pagination, profile, adAccountId) is already documented in the schema. The description contributes nothing further about parameter semantics, so the baseline 3 is appropriate.

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 specific verb ('Read') and resource ('ad-group performance rows'), and the word 'bounded' signals a windowed/paginated result. It does not distinguish this from close siblings like ad_report, campaign_report, or keyword_report beyond the resource level implied by the name.

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?

No when-to-use guidance and no exclusions. With four report tools in the sibling list (ad_report, campaign_report, keyword_report, search_term_report), an agent gets no help deciding which aggregation level or report type to pick, nor any hint about prerequisites such as needing a valid profile and ad account.

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