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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds value beyond that by naming the returned fields (creative, status, review_status), which matters because there is no output schema. It says nothing about pagination or result volume, leaving that entirely to the schema.

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 naming the action, the parent resource, and the returned fields. No filler, no repetition of the title.

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?

For a read-only, 6-parameter list tool with full schema coverage and annotations, the description covers scope and the key returned fields. Missing only a note on pagination behavior and whether the list is bounded, which are minor given the cursor parameters are documented in the schema.

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 (domain_id, ad_group_id, after, before, limit, order) is documented in the schema itself. The description only implies the ad_group_id scoping and adds no format, range, or capping detail. Baseline 3 is appropriate when the schema does all the work.

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 (List) and resource (ads) and scopes it to a ChatGPT Ads ad group, which separates it from get-openai-ads-ad (single) and list-openai-ads-ad-groups/campaigns. It does not explicitly name those siblings, so the differentiation is inferable rather than stated.

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 parent-scoped phrasing implies you call this when you have an ad_group_id and want its ads, but there is no explicit when-to-use/when-not guidance and no pointer to alternatives such as get-openai-ads-ad for a single ad. Usage is inferable from the description only.

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