creatives_preview

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

With no annotations provided, the description carries the full burden. It does reveal that the output is rendered HTML, which is a useful behavioral detail beyond the schema. However, it does not disclose side effects, permission requirements, error cases, or the meaning of 'any ad format', leaving the behavior only partially transparent.

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 a single, concise sentence that front-loads the key information. Every word contributes value, and there is no wasted text.

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 tool with two parameters and no output schema, the description provides the core purpose and return format. However, it lacks guidance on alternatives, parameter details, and error behavior, making it only minimally viable. The sibling ads_get_ad_preview suggests missing context.

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 mentions 'any ad format' which adds some meaning to ad_format, and implicitly refers to creative_id, but it does not explain the valid formats, the default value, or how the required creative_id should be used. This is minimal compensation.

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 ('Preview') and resource ('a creative'), and clarifies the output format ('returns rendered HTML'). It is clear, but it does not explicitly differentiate from sibling tools like ads_get_ad_preview, so it falls short of a 5.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention ads_get_ad_preview or any other potential substitute, nor does it provide context on prerequisites or exclusions. This is a clear gap.

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