list_voices

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

No annotations are provided, so the description carries the burden alone. It does disclose that this talks to a live server and reports server status, which implies a network dependency and a possible unavailable-server condition, but it never states failure behavior, cost, or whether results are cached. Return values are covered by the output schema, so that gap is acceptable.

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?

A single front-loaded sentence stating the resource first, then the downstream use of the result, then the secondary server-status capability. No filler, no repetition of the tool name.

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 zero-argument read tool with an output schema, the description supplies the one thing the schema can't: where the returned voice ids are consumed. The only missing piece is guidance on server-unavailable behavior or the doctor overlap, which is a minor gap at this complexity level.

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 takes zero parameters, which is the documented baseline of 4. The description adds no parameter confusion and correctly frames the output id as an input to another tool's field.

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?

Specific verb+resource ('Danh sách giọng' / list voices) scoped to the VieNeu-TTS server, plus the extra detail that the returned id is what goes in `narrator.voice` in cast.json. That clearly separates it from list_runs or transcribe. It stops short of explicitly distinguishing itself from doctor, which also surfaces server status.

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 parenthetical about `narrator.voice` in cast.json implies when to call it (when configuring a cast), but there is no explicit when/when-not statement or named alternative. The 'tình trạng server' (server status) clause overlaps with the sibling `doctor`, and the description does not say which to prefer.

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