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

Annotations provide readOnlyHint=false (implying it may mutate or have side effects) and openWorldHint=true. The description adds critical behavioral context: it costs money, runs asynchronously, and requires polling with get_generation. This goes beyond what annotations alone reveal, helping the agent understand the operational behavior.

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 brief and front-loaded with the core purpose. Every sentence adds value: it states the function, clarifies cost, and outlines the async requirement. It could be slightly more structured but is efficient and easy to scan.

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?

For a tool with two well-documented parameters and no output schema, the description provides essential operational detail: the async nature and the need to poll get_generation. It does not specify return format of get_generation, but that is covered by the sibling tool's schema. Overall, enough for an agent to proceed confidently.

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 input schema already documents both parameters thoroughly, including enum values for 'keep' and format for 'audio'. The schema description coverage is 100%, so the description adds no additional parameter-specific meaning. The schema does the heavy lifting, so a baseline of 3 is appropriate.

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 primary function: 'Separate vocals and music.' It uses a specific verb and resource, making it immediately distinguishable from sibling tools like ai_audio_translator or ai_speech_to_text. The mention of cost and async behavior adds specificity beyond a generic purpose.

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 on how to use the tool: it explains the async flow, telling the agent to call get_generation until status is 'completed'. However, it does not explicitly state when not to use this tool or mention alternatives, so it lacks explicit exclusions but still gives strong guidance.

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