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

The description adds meaningful behavior beyond the annotations: quote-only with no charge, returns a quote_id for confirmation, and explains that reformat is recomposed rather than cropped. It does not mention quote expiry or that repeated calls may create separate quotes, which would have made it fully transparent given idempotentHint=false.

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 compact and front-loads the most important fact: this is a non-charging quote step. The remaining sentences earn their place by explaining variant kinds and the next step.

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 7-parameter, schema-rich tool with no output schema, the description covers purpose, pricing semantics, the quote_id return, and the confirm_operation handoff. Remaining gaps around idempotency and quote lifetime are minor but real.

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 71%, so the schema already documents several parameters well. The description still adds useful semantic mapping between kind values and parameters, such as translate using languages and reformat using aspect ratios, though it does not cover count, visibility, or voice_id beyond what the schema provides.

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 prices a variant of a ready video and returns a quote_id. It distinguishes the four variant kinds and explicitly frames the tool as step 1 of 2, making it easy to separate from confirm_operation.

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 gives clear usage context by saying this is step 1 of 2, nothing is charged, and the returned quote_id feeds confirm_operation. It does not explicitly compare against alternatives such as get_estimate or state when not to use this tool, so it stops short of full when/when-not guidance.

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