vertical

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

With no annotations, the description carries the full behavioral burden. It says 'fill-crop' but never states whether the source is replaced or written to a new path, whether content outside the crop is lost, what codec/quality is used, or whether the input file is mutated. For a mutation-style render tool this is a significant gap.

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 well-formed sentence with the operation and target front-loaded and zero filler. It is appropriately sized, though its brevity is also the source of the specification gaps.

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 4-parameter tool with no annotations, no output schema, and 0% schema description coverage, one sentence is not enough. Nothing describes return values, output file handling, or how width/height interact with the stated 9:16 target.

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 coverage is 0% across 4 parameters, so the description must compensate and does not. '9:16' loosely maps to the default width/height of 1080x1920, but the description never explains that width/height override the aspect ratio, nor what 'input' and 'output' accept (paths, 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 states a specific verb and resource ('Fill-crop a render') plus the target aspect ratio and destination platforms, which disambiguates the otherwise opaque name 'vertical'. It does not explicitly differentiate itself from siblings like 'conform' or 'side_by_side', but the operation is concrete enough to act on.

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?

Naming TikTok/Reels/Shorts implies the use case, but there is no explicit when-to-use guidance, no mention of when NOT to use it (e.g. versus 'conform' or 'side_by_side' for other output shapes), and no prerequisites. The agent must infer the trigger condition.

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