Estimate what a file will cost

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

Annotations already convey readOnlyHint=false and destructiveHint=false, but the description adds meaningful behaviors: the operation is free, does not start a job, files are retained until kept_until, and the estimate can exceed actual charges for recordings. No contradiction with annotations; the description enriches the behavioral picture.

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 sentences with no redundancy: the first front-loads the core purpose, the second gives actionable reuse guidance, and the third covers a pricing caveat. Every sentence earns its place.

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?

Despite lacking an output schema, the description mentions all key return elements (estimate, file_id, kept_until) and how to use them. For a one-parameter tool with these annotations, this is sufficient; minor omissions like error handling are not critical.

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 schema already fully documents path as an absolute path on this machine (100% coverage). The description adds that the path refers to a local file to be uploaded, which is a minor semantic clarification beyond the schema, but it does not add format or constraint details.

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 tool's function: upload a local file and return the maximum credit cost without starting a job. It distinguishes itself from siblings by positioning as a precursor that returns a file_id for reuse with translate_file or transcribe_recording, making its role unambiguous.

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?

It explicitly instructs the agent to pass the returned file_id to translate_file or transcribe_recording to avoid double upload, giving strong contextual guidance. However, it does not explicitly state when not to use it (e.g., if a file_id is already available), so it lacks formal exclusions.

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