list_voices

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

With no annotations provided, the description carries the full burden. It states the tool lists voices and optionally filters by locale prefix, which implies a read-only, non-destructive operation. It does not disclose error handling or return size, but for a simple listing tool this is adequate coverage.

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 a single, front-loaded sentence with no filler. It efficiently communicates the action, resource, and optional filtering behavior, earning its place entirely.

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?

The tool is simple (one optional parameter, read-only listing) and an output schema exists. The description covers all essential usage context, and the sibling tool name helps situate it within the Edge TTS workflow. No significant gaps remain.

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 schema provides only the parameter name and default with no description. The description compensates by explaining that the locale_prefix is an optional filter and gives concrete examples ('en-US', 'ja'), clarifying both the format and the intended usage.

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 uses a specific verb ('List') and resource ('available Edge TTS voices'), clearly distinguishing it from the sibling tool text_to_speech, which generates speech. The optional locale prefix filter is also stated, making the tool's purpose unambiguous.

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 implies when to use this tool: to discover available Edge TTS voices with optional locale filtering, which is a prerequisite for selecting a voice for text_to_speech. It does not explicitly mention the alternative, but the purpose makes the distinction clear. No exclusions or prerequisites are stated, but the context is easy to infer.

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