save_frame

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

No annotations are present, so the description must carry the full burden. It only mentions output format and purpose; it does not disclose whether the original video is modified, whether the output file is overwritten, or how time_seconds is interpreted. This is a significant gap for a tool that creates files.

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?

Two short sentences, front-loaded with the primary action and then a brief use case. No superfluous 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?

With 3 parameters, no annotations, and 0% schema coverage, the description is underspecified. It doesn't mention return values, error conditions, or behavior for invalid time_seconds, so an agent may misinvoke the tool.

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%, so the description needs to compensate. It adds 'single frame' which implies time_seconds selects a frame, but it doesn't explain units, default, or output_path semantics. clip_id and output_path are left to inference from their names, offering minimal value beyond 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?

Description clearly states the tool saves a single frame from a video as an image file in png/jpg format. This is a specific verb+resource+format that distinguishes it from sibling tools like trim, export_clip, and load_image.

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?

States it is useful for thumbnails or previewing an edit, providing clear use case context. However, it doesn't explicitly mention when not to use it or name alternative frame-extraction tools.

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