google_ads_performance_analyze

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

No annotations are provided, so the description fully carries the burden. It discloses read-only nature, default period, graceful failure of subcomponents returning 'Retrieval failed', and detailed return shape including optional fields. No contradictions.

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 fairly comprehensive but well-structured, front-loading purpose and return shape. Each sentence contributes useful information. Slightly long but justified by the tool's complexity.

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 tool's complexity (multiple sub-reports) and no output schema, the description thoroughly explains the return object, failure behavior, defaults, and usage alternatives. It covers all necessary context for an agent to invoke 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 coverage is 100%, so the baseline is 3. However, the description adds context beyond the schema: customer_id fallback to credentials, campaign_id source via google_ads_campaigns_list, and the period being tuned for short-horizon comparison. This adds meaningful guidance.

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 diagnoses a single Google Ads campaign by composing current-vs-previous comparison, top search terms, Google recommendations, and recent change history. It explicitly distinguishes from sibling tools like google_ads_cost_increase_investigate and google_ads_health_check_all.

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 provides explicit when-to-use (diagnose a single campaign) and when-not-to-use (for cost-spike or account-wide health, pointing to alternatives). It also specifies default period and options for longer baselines.

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