Draw box

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

With no annotations, the description carries the full burden of behavioral disclosure. It clearly explains the two key behavioral options: outline vs. filled box and the optional time range. It does not mention output behavior or side effects, but the schema includes input_path and output_path, making the non-destructive nature implicitly clear.

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 a single, front-loaded sentence that delivers the core purpose and key options without redundancy. Every word earns its place, making it highly concise and effective.

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?

Given the tool's moderate complexity (11 parameters) and rich schema coverage, the description adequately covers purpose and notable features. It does not explain return values, but the presence of output_path in the schema mitigates this gap. The description is sufficiently complete for an agent to select and invoke the tool correctly.

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 baseline is 3. The description adds little beyond the schema, only reinforcing the fill and time-range concepts already documented in the parameter descriptions. No additional syntax or format details 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 uses a specific verb 'Draw' and identifies the exact resource: a rectangle outline or filled box on a video. It clearly distinguishes this tool from siblings like add_text_overlay, add_watermark, and blur_region by stating its purpose of highlighting or redacting a region.

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 provides clear context for when to use this tool: for highlighting or redacting a region on a video. It does not explicitly name alternatives or exclusions, but the use case is well-stated and distinct from sibling tools.

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