GA4 realtime report

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds the time window (last 30 minutes) and lists available dimensions/metrics, which is useful behavioral context beyond annotations. It does not disclose potential limitations like data availability or latency, but given the annotation coverage, this is sufficient.

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 a single, dense sentence that front-loads the core purpose (real-time GA4 data) and then lists supported dimensions and metrics. Every word adds value, with no fluff or repetition. It is optimally concise.

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 simple read-only tool, the description covers the essential aspects: data freshness (last 30 minutes) and valid dimensions/metrics. It does not mention pagination or limit behavior, but the schema provides defaults and bounds. There is no output schema, but the description implies the nature of the returned data. Overall, it is complete enough for an agent to call the tool correctly.

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 25% (propertyId has a description). The description compensates by listing valid dimension and metric names, which directly informs the 'dimensions' and 'metrics' array parameters. This adds meaning beyond the schema, though it does not explain the format of arrays or default behaviors (covered by defaults in schema). The propertyId hint in the schema is also helpful.

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 provides real-time GA4 data for the last 30 minutes, listing specific dimensions and metrics. This distinguishes it from sibling tools like ga_run_report (which likely handles historical data) and ga_compare_periods. The verb 'Real-time' and resource 'GA4 data' are explicit and unambiguous.

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 description implies usage for real-time data by stating 'last 30 minutes', but does not explicitly say when to use this tool versus alternatives such as ga_run_report. There is no direct statement of 'use this for immediate data' or 'use ga_run_report for historical data'. The real-time scope is a clear hint, but explicit guidance is missing.

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