Add text overlay

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does mention the time-range option ('Optionally limited to a time range'), which is a useful behavior, but it omits other important details such as whether the source file is modified, the default output behavior, or how the overlay interacts with existing video content. This is insufficient given the lack of annotations.

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 short sentences and front-loaded with the core action. Every word serves a purpose, with no redundant information. It is appropriately concise.

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 schema covers all 9 parameters, so the tool is functionally clear. However, the description lacks usage guidelines and behavioral context beyond the time-range option. For a tool with no annotations and no output schema, a score of 3 reflects that it is adequate but has clear gaps in contextual completeness.

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 description coverage is 100%, so the baseline is 3. The description adds no additional meaning beyond the schema; 'time range' hints at start/end parameters, but those are already fully described in the schema. No extra parameter semantics are provided.

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 clearly states the action: 'Draw text on the video' and lists example uses (caption, title, label). It distinguishes from siblings like burn_subtitles and add_watermark by focusing on general text overlay rather than subtitle files or image watermarks.

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?

No guidance on when to use this tool versus alternatives. The description does not mention siblings like add_watermark or burn_subtitles, nor does it specify contexts where a text overlay is preferred. The only hint is the parenthetical 'caption, title, label', but it does not constitute explicit usage guidance.

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