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

Annotations already declare this as read-only, non-destructive, and open-world, so the description is not burdened with safety disclosure. It adds substantial behavioral context by enumerating the exact checks performed (smart bidding with conversions, CPC escalation, budget overruns, geo leakage, GA4 engagement, policy disapprovals, favicon-as-logo, informational search terms) and by explaining that findings are severity-ranked. It does not discuss runtime, rate limits, or failure modes when GA4 is missing, but the added detail is well beyond 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 front-loaded with the one-sentence purpose and then lists checks in a compact run-on list, followed by the breakdown coverage. It is longer than most tool descriptions, but the enumeration of checks is useful for deciding whether to call the tool. Minor improvement would be breaking the check list into structured bullets, but no sentence is clearly wasted.

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?

Given the complexity of a multi-check audit, the description covers what is inspected and what breakdowns accompany the findings, and an output schema exists so return values need not be fully restated. Remaining gaps are prerequisites (MCC access, GA4 linkage requirements) and the boundary against cheaper raw-data siblings like ads_query, which would make the definition fully self-sufficient.

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 the baseline is a 3, and the description adds little parameter-level meaning. It only implicitly connects GA4 to the 'low engagement' check, which the schema already covers with 'adds landing-quality checks,' and it never clarifies date_preset behavior or how login_customer_id affects account resolution.

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 states a specific verb (audit) and resource (one Google Ads campaign) plus a return contract: findings ranked by severity plus breakdowns. That is far more precise than sibling tools like ads_query or get_data, and an agent can distinguish this analytical tool from the raw-query siblings without opening any schema.

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 audit scope implies when the tool is useful, but the description never states explicit when-to-use or when-not-to-use guidance. It also does not name alternatives such as ads_query for raw data or get_data for fetching campaign ids, and it gives no prerequisites like minimum date range or conversion volume needed for the bidding checks to be meaningful.

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