google_ads_auction_insights_get

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

Despite no annotations, the description fully discloses behavioral traits: it is read-only, describes the return format in detail (fields, types, failure cases with two error types), and explains the limitation about competitor-level data removal in the API. This provides complete transparency for safe invocation.

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 moderately sized but every sentence earns its place. It is front-loaded with the main purpose and structured logically. Slight redundancy in listing fields, but overall efficient.

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 there is no output schema, the description fully explains the return value structure. It addresses all parameters, provides practical usage hints, documents API changes, and differentiates from related tools. No gaps remain for an agent to correctly invoke the tool.

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% with good descriptions, and the description adds value by explaining fallback behavior for customer_id, the purpose of campaign_id (obtain via list tool), and providing usage suggestions for the period parameter (e.g., 'Use a shorter window...'). This goes beyond mere parameter listing.

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 'Fetch raw impression-share metrics for one Google Ads campaign' with a specific verb and resource. It distinguishes itself from the sibling tool 'google_ads_auction_insights_analyze' by explicitly noting the latter provides human-readable insights.

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 explicitly says 'Read-only' and provides guidance on when to use shorter windows (LAST_7_DAYS/LAST_14_DAYS) for recent changes and longer windows (LAST_90_DAYS) for trend baselines. It also highlights the API version change (v23) and directs to a sibling tool for richer insights, offering clear when-to-use and when-not-to-use guidance.

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