list_tts_models

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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds that generation is synchronous and returns audio directly, but that is about generate_tts, not about this listing call's own behavior (caching, latency, return shape), so the added value is modest.

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?

Three short sentences, front-loaded with the purpose and zero wasted words. The closing sentence about synchronous generation is slightly off-topic for a listing tool but earns its place as downstream workflow context.

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-parameter, read-only listing tool with no output schema, the description is sufficient to pick and call it correctly. It could say more about the shape of the returned channel/parameter data, but the complexity is low enough that this is a minor gap.

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, so there is nothing for the description to document; baseline is 4. 'Channels and parameters' refers to returned content rather than inputs, so no input semantics are needed or missing.

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?

States a specific verb and resource ('List TTS channels and parameters'), clarifying what the 'models' in the name actually are, and the TTS qualifier distinguishes it from sibling list_music_models / list_video_models / list_sts_models. It stops short of explicitly naming those siblings as the thing it is not.

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?

Gives clear workflow context by pointing to list_voices with operation=tts as the next step to obtain a voice_id, which implies this tool is used when assembling a TTS generation request. It does not state explicit exclusions versus other list_* tools, but the sequence guidance is concrete.

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