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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered and the description only needs to add operational context. It adds the GA4 Data API framing and the property resource format, but says nothing about quotas, throttling, or whether the default limit of 10000 truncates results.

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 that defines the operation before any details. The trailing "Tools revision: d80f65c0." is build metadata that adds no selection or invocation value for an agent.

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 format need not be described, and annotations cover the read-only profile. However, for a 6-parameter analytics query tool with zero schema descriptions, the gaps around date formatting, metric naming and limit behavior leave real ambiguity an agent must resolve by trial and error.

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 0% across 6 parameters, so the description carries the full burden and only partly meets it. It clarifies the property as "properties/<id>" and explains that dimensions combine with metrics over a date range, but gives no date format (e.g. YYYY-MM-DD vs relative strings), no metric/dimension naming examples, and no semantics for the limit parameter.

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 ("Run a GA4 Data API report") and scopes it as "dimensions x metrics over a date range," which implicitly separates it from the cohort, funnel and realtime report siblings. It does not explicitly name those siblings, so an agent must still infer that ga4_run_pivot_report is the variant for pivoted output.

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 scope phrase implies this is the general-purpose reporting tool, but there is no explicit when-to-use or when-not-to-use statement and no routing to ga4_run_pivot_report, ga4_run_cohort_report, ga4_run_funnel_report or ga4_run_realtime_report. Usage is inferred from the parenthetical rather than stated.

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