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

The description adds a behavioral hint ('Paid ones must be ordered first') that is not in the annotations, but it is ambiguous and does not clarify whether it is a requirement or an output ordering. Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description adds limited value.

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 very short and contains no filler, but the phrasing is more descriptive than instructive. It is not front-loaded with an action verb, making it less clear as a tool instruction.

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 simple zero-parameter tool, the description should be unambiguous about what it does. It fails to clearly state that it lists voices, and it provides no usage context. This is insufficient for an agent to confidently invoke it.

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 description need not explain any. The schema is fully covered (vacuously), and the baseline for 0-param tools is 4, which 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 is vague and does not explicitly state the action of listing. It describes the concept of 'voices' rather than what the tool does, relying on the tool name for meaning. It is not a tautology but lacks a clear verb+resource phrasing.

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?

No guidance is provided on when to use this tool versus sibling list tools (e.g., list_drinks, list_rooms). There is no mention of alternatives, conditions, or context that would help an agent decide to call this specific tool.

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