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

Beyond the sparse annotations, the description discloses critical behavior: the operation consumes paid generation allowance, is asynchronous, and has a specific failure-refund policy. This is exactly the kind of behavioral context an agent needs before invoking a paid generation tool.

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?

Three short sentences, each earning its place: what the tool does, the cost implication, and the required follow-up behavior. No filler or repetition of schema content.

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 complex 13-parameter tool with nested objects and an output schema, the description plus schema covers the essential workflow: start generation, poll via get_ad_studio, and know the failure cost behavior. Nothing critical 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%, so the schema already documents every parameter. The description adds no extra parameter-level meaning, which is acceptable because the schema carries the burden. Baseline 3 is appropriate.

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 opens with a specific verb and resource ('Start a paid Ad Studio clip'), which clearly identifies the action and target. It also distinguishes itself from quote/research/get siblings by emphasizing that this tool starts the actual paid generation.

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 gives clear operational context: it uses this month's allowance, requires polling get_ad_studio, and hard failures return the allowance. It does not explicitly name alternatives or say when not to use it, but the paid-generation context makes the intended use obvious.

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