change_speed

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

With no annotations, the description carries the responsibility to disclose behavioral traits. It does so by noting that 'audio pitch is preserved' and explaining speed_factor semantics with examples. However, it does not mention output file handling (e.g., overwriting) or potential side effects, leaving some room for added detail.

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 extremely concise, containing only two sentences. It is front-loaded with the main action and immediately provides the key parameter guidance, with no wasted words.

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 tool is simple with no output schema, and the description sufficiently covers its core functionality and parameter semantics. It does not explain return values, but for a file-processing tool this is often unnecessary. The input/output paths are fully described in the schema, so the description is complete enough for effective use.

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 description adds crucial meaning to the speed_factor parameter, which lacks a schema description: 'speed_factor > 1 speeds up, < 1 slows down (e.g. 2 = 2x faster, 0.5 = half speed).' This compensates for the missing schema coverage for that parameter, while input_path and output_path are adequately described in 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?

The description clearly states the tool's function: 'Speed up or slow down a video.' This is a specific verb+resource pair that distinguishes it from sibling tools like trim_video or adjust_volume, which address different video properties.

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 for changing playback speed but provides no explicit 'when to use' or exclusions. It does not mention alternative tools or cases where this tool should not be used, such as when only trimming duration is needed. The context is clear but not elaborated.

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