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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint, and openWorldHint, so the safety profile is covered. The description adds useful behavioral context by noting the sample is fixed, the result is cached, and the visible output includes transcript, segments, and WebVTT shape.

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?

It is a single compact sentence with the core distinction, caching behavior, and return-shape summary front-loaded. No sentence is wasted.

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 zero-parameter schema, rich annotations, and no output schema, the description is complete enough: it explains the fixed-sample scope, cached behavior, and what output shape the agent can expect.

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?

There are zero parameters, so parameter semantics require no explanation. The description appropriately reinforces that the tool operates on a fixed sample and takes no user-supplied audio.

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 a specific demo action on a named resource: a free demo of speech_to_text using a fixed cached MP3. It distinguishes itself from the sibling speech_to_text tool by making clear this is a fixed-sample demo, and it also names the output areas shown.

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 phrase 'Free demo ... on a fixed sample MP3 (cached)' gives clear usage context: this is for previewing speech_to_text behavior without supplying real audio. However, it does not explicitly say to use speech_to_text instead when real transcription is needed.

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