Google Analytics report

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds one useful return detail ('rows plus metric totals'), but says nothing about pagination, row limits, quota/throttling, or how the 9/10 dimension-metric caps behave. Moderate added value over annotations.

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 front-loaded sentence with the core action first, followed by an illustrative list and a brief return clause. The dimension/metric examples are long but each earns its place given the absent schema documentation for those arrays.

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 an 8-parameter tool with nested filter and orderBy objects and no output schema, the description covers what the report can contain and roughly what it returns, but leaves sibling disambiguation, date semantics, and limit/pagination unexplained, so an agent may still need to infer.

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 only 38% (limit, startDate, endDate, dimensions, metrics are undocumented in the schema), so the description must compensate. It partially does so by giving example dimension and metric names, but adds nothing about date formats, limit behavior, or how filters/orderBy combine beyond what the schema already states.

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 and resource ('Runs a GA4 report') and enumerates the dimension/metric families it accepts, which is more concrete than a restatement of the name. It does not, however, distinguish itself from closely related siblings like ga_realtime or compare_periods.

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 and no mention of alternatives. An agent cannot tell from this description why it should call ga_report instead of ga_realtime, compare_periods, or search_analytics for an analytics question.

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