save_audio

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

Without annotations, the description should fully disclose behavior. It covers parameter ranges and fallback to environment variable for speaker, but lacks details on file overwriting, error handling, or return value specifics (output schema exists but its content is unknown).

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 structured with a title, Args section, and Returns line. It is front-loaded and concise, though some defaults are redundantly listed when already in schema. No extraneous sentences.

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 tool with 7 parameters and no schema descriptions, the description explains all parameters and references sibling tools. Minor omissions like file overwrite behavior or return message format prevent a higher score.

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?

Schema description coverage is 0%, but the description provides full semantic detail for all 7 parameters: ranges, defaults, and how to obtain speaker IDs. This compensates completely for the schema gap.

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 it synthesizes text with VOICEVOX and saves as WAV file, specifying the technology and output format. It distinguishes from sibling 'list_speakers' by referencing it for speaker IDs, and 'speak_text' likely does not save.

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 explains when to use the speaker parameter and directs to list_speakers for available IDs. It does not explicitly differentiate from speak_text or state conditions for not using the tool, but the context is clear for main use.

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