list_voices

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

There are no annotations, so the description carries the behavioral disclosure burden. It makes clear this is a read-only listing operation ('Lista') and discloses the return shape: 'Retorna um JSON contendo uma lista de objetos com id, elevenlabs_id e name.' It does not discuss auth, rate limits, or edge cases, but for a simple list operation this is reasonably transparent.

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 three sentences, each earning its place: what the tool lists, when to use it, and what it returns. It is front-loaded with the primary purpose and contains no filler or repetition.

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 takes no parameters, has an output schema available, and is a straightforward listing operation, the description is complete. It provides the usage context, the type of content, and the return format, which is enough for an agent to select and invoke it correctly.

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 tool has zero parameters, so the baseline is 4. The description adds contextual meaning about how the returned voices are used (for narration and jingles) even though no parameter documentation is needed.

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 opens with a specific verb and resource: 'Lista todas as vozes comerciais disponíveis no QuickerSpot para narração e vinhetas.' It clearly identifies what is listed and the intended content domain, and it is easily distinguishable from sibling tools like list_campaigns and create_campaign.

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 explicitly tells the agent when to use the tool: 'Utilize esta ferramenta antes de criar uma campanha ou recado para escolher o timbre de voz mais apropriado.' It provides clear context but does not explicitly name alternatives or state when not to use it, so it stops short of a 5.

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