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

Annotations already declare this is a non-read-only, non-destructive, open-world operation. The description adds important behavioral context about OAuth credits versus API-key USD billing and the quote-confirmation flow, though it does not mention output format or whether transcription is synchronous.

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 front-loaded with the core purpose and then covers billing details in two compact sentences. The billing explanation is dense but each sentence carries relevant information.

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?

The description covers the critical cost and auth workflow, which is valuable for an open-world write tool with no annotations about billing. It remains incomplete about return format, output structure, and whether the caller should expect a job/polling flow, which matters more because there is no output schema.

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 100%, so the schema already documents all six parameters in detail. The description reinforces the OAuth versus API-key billing dependencies, but it also references an 'approval' action that does not appear as a parameter in the schema, which may create slight confusion.

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 clear verb and resource: turning speech in a recording into text. It is semantically distinct from siblings like create_speech, but it does not explicitly name alternatives or route the agent among siblings.

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 gives billing workflow guidance, including omitting approval to get a quote and confirming max_credits or max_usd afterward. However, it does not say when to choose this tool over alternatives such as create_speech or other audio tools.

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