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

The description adds the supported input video containers and output audio formats, which are not in the annotations. It also states the result is a download, but does not describe the response format (e.g., direct file link, JSON with URL) or any processing side effects. Annotations already convey read-only/non-destructive nature, so the description adds moderate but not rich context.

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: two sentences with no filler. The first sentence states the action and formats, the second provides usage guidance. All information is front-loaded and every word contributes to the tool's utility.

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 there is no output schema, the description should explain what the tool returns. It says 'download as MP3 or WAV,' implying a downloadable artifact, but doesn't clarify the response structure (e.g., binary payload, URL, or file token). For a tool with 6 parameters and multiple upload methods, the description covers the core action but leaves output expectations ambiguous.

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 descriptions already cover all 6 parameters with 100% coverage, so the baseline is 3. The description adds value by specifying accepted video formats (MP4, MOV, WebM, M4V), which is not in the schema, and by clarifying target_format as the output selection (MP3/WAV). This extra context improves agent comprehension beyond the schema alone.

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 extracts audio from video files (MP4, MOV, WebM, M4V) and converts to MP3 or WAV. The verb 'Extract' and resource 'audio track' make the purpose unambiguous, and it distinguishes itself from sibling audio tools like converter or trimmer by focusing on video sources.

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 second sentence explicitly says 'Use this when the user wants to get audio out of a video file,' providing clear context for when to select this tool. However, it does not mention when not to use it or name alternative tools, so it lacks the full exclusions/alternatives guidance seen in the highest-calibration examples.

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