PPC Ad Editor

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds value beyond that by disclosing the shape of the returned data (field counts, character limits, supported media), which matters because there is no output 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 with zero filler; the list of returned fields is the most useful information and appears immediately.

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, read-only, one-optional-parameter lookup with no output schema, the description adequately covers what is returned. It could be marginally more complete by stating that omitting the filter returns all formats, but nothing an agent needs in order to call it correctly is missing.

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% and the single 'formats' parameter is documented there as an optional filter with a full enum. The description says nothing about the filter or the behavior when it is omitted (return all formats), so it adds no meaning beyond the schema — baseline 3.

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 ("Returns the full specification for each ad format") and enumerates the contents (field counts, character limits, supported media), so an agent knows exactly what it gets back. It does not name or contrast with the sibling preview_ad, which is the only missing element for 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?

Usage is only implied: the description suggests looking up specs, but never says when to call this versus preview_ad, nor that it should be used before composing an ad. No exclusions or prerequisites are stated.

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

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

Beyond the read-only and non-destructive annotations, the description discloses that it does not generate images, requires hosted HTTPS image URLs, explains how external images are routed through signed URLs, and notes that the result includes save_url. These are meaningful behavioral details for an agent to understand before calling.

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 front-loaded with the core purpose and then organized into useful format specs. It is long, but the length is largely justified by 10 formats and 15 parameters; some operational details could be tightened.

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?

The definition is largely complete for invoking the tool: it covers image constraints, one-format-per-call behavior, and save_url. With no output schema, it could more fully describe the return shape beyond save_url, but the invocation-critical context is present.

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?

Although schema description coverage is already high at 93%, the description adds substantial meaning by listing per-format field allowances and character limits. It also clarifies field distinctions such as Google Search not using primary_texts and extensions being ignored on non-Google formats.

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: 'Show a realistic mockup of one ad' and lists the supported ad formats. It clearly distinguishes previewing from generating images, but it does not explicitly differentiate itself from the sibling get_ad_formats tool.

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?

It gives useful context such as 'No account needed,' 'One format per call,' and that ad copy comes from the caller. However, it does not explicitly say when to use this tool versus get_ad_formats or when not to use it.

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