video_resize

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

With no annotations provided, the description carries full burden but provides minimal behavioral disclosure. It mentions that output_path is 'auto-generated if omitted', which is useful context. However, it doesn't describe permissions needed, whether the operation is destructive to the original file, performance characteristics, error conditions, or what the output contains (though output schema exists).

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 appropriately sized and front-loaded with the core purpose in the first sentence. The parameter explanations are organized in a clear Args section. While efficient, the quality preset values could be more concisely formatted, and some behavioral context is missing.

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 6 parameters with 0% schema coverage and no annotations, the description does well on parameters but lacks behavioral context for a mutation tool. The existence of an output schema means return values don't need explanation, but the description should still address permissions, side effects, and error handling more explicitly.

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 0%, so the description must compensate. It provides meaningful explanations for all 6 parameters beyond their titles: clarifies that width/height work together, aspect_ratio overrides them, lists preset values for aspect_ratio and quality, and explains output_path behavior. This adds substantial value over the bare 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?

The description clearly states the tool's purpose with specific verbs ('resize', 'change aspect ratio') and identifies the resource ('video'). It distinguishes from siblings like video_crop, video_convert, and video_trim by focusing specifically on resolution/aspect ratio modification rather than cropping, format conversion, or trimming.

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 implies usage through parameter explanations (e.g., 'Use with height', 'Overrides width/height'), suggesting when to use width/height vs aspect_ratio. However, it doesn't explicitly state when to choose this tool over alternatives like video_crop or video_convert, nor does it mention prerequisites or exclusions.

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