GA4 report

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the description need not repeat these. It adds context that a comparison date range introduces a 'dateRange' dimension and lists common dimensions/metrics, but it does not disclose return format, pagination behavior, or rate limits. This is acceptable given the 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?

The description is concise, front-loaded with the core purpose, and uses a few sentences to convey key information. The list of common dimensions/metrics is useful but slightly lengthy; it earns its place by guiding parameter selection. No unnecessary fluff.

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 report tool with no output schema, the description provides enough to call it correctly: property ID, dimensions, metrics, date range, and optional comparison. It points to ga_get_metadata for extended metadata. Missing details like return format are minor given the tool's nature and the provided annotations.

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 coverage is 53%, and the description compensates by listing common dimensions and metrics, which helps agents populate the arrays. It also explains that compareStartDate adds a 'dateRange' dimension, adding meaning beyond the schema. The pointer to ga_get_metadata further supports parameter discovery.

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 clearly states the tool runs a Google Analytics 4 Data API report, lists common dimensions and metrics, and points to ga_get_metadata for discovery. It implies a distinction from real-time and comparison tools but does not explicitly contrast with siblings like ga_run_realtime_report or ga_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?

The only usage guidance is 'Use ga_get_metadata to discover more.' It does not state when to use this tool versus alternatives like ga_run_realtime_report or ga_compare_periods, nor does it mention prerequisites or exclusions. The optional comparison date range hints at overlap with ga_compare_periods but is not clarified.

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