calculate_rewrite_quota

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

With no annotations provided, the description carries the full behavioral burden and handles it well: it clearly states the operation is non-charging ('不扣费'), explains the pricing basis (video duration), and corrects the misconception that rewriting is free. It does not discuss auth or side effects, but the non-destructive nature is explicitly disclosed.

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 three tight sentences with no filler. It front-loads the core purpose, adds the no-charge caveat, gives pricing context, and ends with a practical usage note. 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?

The tool has one required parameter, full schema coverage, and no output schema. The description explains the quota semantics and even tells the agent to report the number to the user, which partially covers the return value. Since there is no output schema, a bit more explicit detail about the returned format could help, but the context is adequate for a simple calculator.

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 both parameters are already fully documented. The description adds no new parameter-level detail, but it does supply useful pricing context that helps the agent understand why order_no matters. This matches the baseline of 3 when the schema handles parameter documentation.

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 verb and resource: it calculates quota for regenerating a video with corrected subtitles, and explicitly notes it does not charge ('不扣费'). It also distinguishes this from first-time translation by explaining rewrite is a new translation task priced identically, not a free rework.

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 clear context for when to use the tool: before proofreading/correcting subtitles, ask this first and relay the number to the user. It implies this is the right tool for rewrite-cost questions rather than initial translation quota, though it does not explicitly name sibling tools or state when not to use it.

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