video_add_audio

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions that audio can be added or replaced and that output can be auto-generated, but lacks details on permissions, rate limits, error handling, or what happens to the original video file. For a mutation tool with 8 parameters, this is insufficient transparency.

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 well-structured and appropriately sized. It starts with a clear purpose statement, followed by a bullet-point list of parameters with concise explanations. There's minimal waste, though the 'Args:' header is slightly redundant. Overall, it's efficient and easy to parse.

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 complexity (8 parameters, mutation operation) and the presence of an output schema (which reduces the need to describe return values), the description is moderately complete. It covers parameter semantics well but lacks behavioral context like error conditions or side effects. With no annotations, it should do more to guide safe usage.

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 significant meaning beyond the input schema, which has 0% description coverage. It explains each parameter's purpose (e.g., 'volume: Audio volume (0.0 to 2.0, where 1.0 = original)', 'mix: If true, mix with existing audio. If false, replace it.'), clarifying semantics that the schema alone doesn't provide, fully compensating for the schema's lack of descriptions.

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: 'Add or replace the audio track of a video.' It specifies the verb ('add or replace') and resource ('audio track of a video'), making the function unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'video_extract_audio' or 'video_merge', which prevents a perfect score.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools (e.g., 'video_extract_audio' for extracting audio, 'video_merge' for combining videos) or specify prerequisites like file formats or permissions. Usage is implied by the function but not explicitly contextualized.

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