get_ad_details

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the read-only behavior is covered. The description adds useful output context by listing ad details like headlines, descriptions, URLs, and assets, but it does not disclose other behavioral aspects such as response size, errors, or permissions. This is adequate given 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 compact and front-loaded with the tool's purpose. The Arg list is necessary because the schema provides no parameter descriptions, and every line contributes useful, non-redundant context. No filler or promotional language appears.

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 simple three-parameter, read-only tool, the description is mostly usable. However, with no output schema, the return-value description is only a high-level list of content categories and does not explain the response structure or how these fields are organized. It is minimally viable but leaves gaps.

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 0%, so the description must compensate. It does provide an Args section explaining each parameter: customer_id is a Google Ads customer ID, ad_group_id is the containing ad group, and ad_id is the ad ID. This adds some meaning beyond the bare schema titles, but the descriptions remain shallow and largely restate the parameter names.

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 uses a specific verb and resource: "Get full details of an ad," and enumerates the content areas returned (headlines, descriptions, URLs, assets). This clearly distinguishes it from sibling tools like list_ads (listing ads) and get_ad_group (ad group details).

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 implies usage: when a caller needs complete details for a specific ad after already having the three IDs. However, it does not explicitly state when to prefer this over list_ads, get_ad_group, or other detail-fetching tools, nor does it mention how to obtain the required IDs.

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