Sample frames (contact sheet)

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

No annotations exist, so the description carries the responsibility. It discloses key behavior: evenly-spaced sampling, timestamps on tiles, and a single output image. It lacks mention of overwrite semantics or format constraints, but for a media-generation tool, the disclosed behavior is sufficient to set expectations.

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 two sentences, 28 words, front-loading the action and output. Every word contributes; there is no redundant or filler 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 tool of moderate complexity, the description explains the purpose, the output, and the workflow. A minor gap is the optional output_path not having a default mentioned, and no explicit mention of image format. These are minor and do not undermine task completion.

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 schema covers all five parameters with descriptions and constraints (count, columns, tile_width, input_path, output_path), so the description is not required to compensate. The description adds no parameter-specific guidance beyond the schema, matching the baseline for high schema coverage.

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 specifies a clear verb and resource: 'Tile evenly-spaced frames from across the video into one image'. It also adds distinctive details (timestamp stamping) that separate it from sibling tools like extract_frame or detect_scenes, making the tool's purpose highly unambiguous.

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 explicit context for when to use the tool: 'Use this to SEE what's in a video before deciding how to edit it'. This tells the agent the intended workflow. However, it does not name alternatives or state when not to use it, so it stops short of full exclusion guidance.

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