Google Ads Transparency lookup

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

Annotations cover the safety profile (readOnlyHint=true, destructiveHint=false), and the description adds genuinely new operational facts: newest-first ordering, a 200-per-call cap, and explicit per-ad pricing ($1/1,000 ads, $0.80 on Gold+). The non-idempotent ordering claim is consistent with idempotentHint=false, so there is no contradiction.

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?

Front-loaded with the resource and return contents, then lookup methods, then cost – a sensible order. It is a single dense paragraph and the enumerated return-field list is slightly long, but every clause carries information.

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?

With no output schema, the description carries the return-value burden and does so thoroughly (format, dates, days running, headline, texts, URLs, images, video). Combined with the cost disclosure, ordering, and cap, an agent has everything needed to call it 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 100%, so every parameter (advertiser, format, region, max_results, include_ad_content) is already documented in the schema. The description restates lookup modes and the 200 cap but adds no syntax or semantics beyond structured fields, so the baseline of 3 applies.

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 ('Every ad an advertiser runs on Google Search, YouTube, Display and Shopping') with the data source named (Google's Ads Transparency Center). Distinct from siblings like search_google_shopping (product listings) and search_google_images/videos (organic search), so an agent can route correctly without opening a 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?

Gives an explicit use case ('competitor ad research and creative inspiration') and describes the input modes for lookup, plus filters by country and format. However it never states when NOT to use it or names an alternative sibling tool, so the guidance is clear context rather than routing rules.

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