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

Beyond the annotations, it discloses important side effects: clip times survive rate changes, pictures are refitted according to their fit with contain as the default, and the result warns how many clips no longer fill the frame. It also explains the relevant follow-up action and points to server instructions for the edit result.

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 main action, then adds only necessary behavioral details and a concrete alternative. Every sentence contributes information needed to invoke the tool correctly, with no filler.

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?

Given the nested schema, annotations, and existing output schema, the description supplies the key behavioral context an agent needs: what changes, how clip timing and fitting are affected, what warning to expect, and how to resolve framing issues. The return value is appropriately delegated to the server instructions and output 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?

The description maps the core sequence object to resolution, frame rate, and audio format, which adds useful meaning beyond the schema. It does not explain the preview parameter, the fps numerator/denominator structure, or optional fields like channels and color, leaving some parameter semantics to the schema.

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 states a specific verb and resource: change resolution, frame rate, or audio format. It is clearly distinguishable from sibling tools such as clip.set_transform, which is explicitly named as the alternative for filling the frame after a sequence change.

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 clear context for when to use the tool and names clip.set_transform {fit: "cover"} as the follow-up alternative when clips no longer fill the frame. It does not explicitly state when not to use it or contrast it with timeline.create or timeline.load, so it falls short of full when/when-not guidance.

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