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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description usefully compensates for the absent output schema by naming the returned fields (counts per language and country variant, catalog link), but says nothing about pagination, ordering, or freshness of the counts.

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 compact sentence that front-loads the resource and enumerates the payload. Slightly dense phrasing ('The languages Worder voices speak') but no wasted text.

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-argument listing tool with a rich annotation set, the description covers the essential return payload. The lack of an output schema is mostly offset, though ordering/pagination behavior remains unstated.

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?

Zero parameters, so the baseline is 4; there is nothing for the description to clarify beyond confirming this is a parameter-free catalog call.

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 states the resource being returned (languages spoken by Worder voices) and its contents, so an agent can tell it targets language metadata rather than voices themselves. It doesn't use a verb like 'list', but the resource is unambiguous and distinguishable from get_voice and search_voices.

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 on when to call this versus search_voices or get_voice, and no mention of it being a no-argument catalog/reference lookup. The agent must infer usage from the name alone.

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