retell_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. The verb 'List' clearly indicates a read-only, non-destructive operation, and the description discloses the type of data returned (provider, gender, accent, preview URLs). No contradictions exist. It lacks explicit statements about pagination or auth, but such details are not critical for this simple list tool.

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, information-dense sentence. Every word earns its place, stating what the tool does and what data it returns without any fluff 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's simplicity (no parameters, no output schema), the description is complete. It specifies the action and the content of the response (provider, gender, accent, preview URLs), which is all a user needs to select and invoke this tool 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 schema is trivially 100% covered. Per the rubric, a parameterless tool receives a baseline score of 4. The description does not need to explain parameter semantics, and no gaps exist.

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 clearly states the action ('List'), the resource ('voices'), and the specific context ('for Retell AI agents'). It also enumerates the fields included (provider, gender, accent, preview audio URLs), making the tool's purpose unambiguous and distinct from sibling tools like retell_list_agents or retell_list_llms.

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 usage: call this when you need to discover available voices for Retell AI agents. It provides clear context but does not explicitly mention alternatives or exclusions. Since there is no other voice-listing sibling tool, this level of guidance is sufficient.

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