transcode_video

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

With no annotations, the description carries the behavioral burden. It discloses that the video is 're-encoded' and that unknown aspect values are rejected with no silent fallback. However, it does not state whether the input file is overwritten or a new file is created, nor what the tool returns, which are important traits for a transformation 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?

A single, tightly written sentence that front-loads the core purpose, specifies the allowed values, and includes a useful behavioral caveat. Every part earns its place 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?

The transformation semantics are clear, but with no output schema and no annotations, the description omits what happens after encoding: whether a new file is produced, whether the original is preserved, and what the agent receives as a result. These are meaningful gaps for a tool that takes a local path and produces an encoded output.

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 100%, so the baseline is 3. The description reinforces the aspect enum by listing the values in prose and adds the rejection behavior, but it adds no new meaning for video_path or quality beyond what the schema already documents.

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 ('Normalize'), resource ('a video'), and the exact transformation (fixed aspect ratio with padding, re-encoded). It also lists the three allowed aspect ratios, which clearly differentiates it from sibling tools like trim_video, crop_video, or convert_format.

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 use case is implied by 'Normalize a video to a fixed aspect ratio', but there is no explicit when-to-use or when-not-to-use guidance, nor any mention of alternatives. An agent must infer that this is for aspect-ratio normalization rather than crop_video or convert_format.

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