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

The description adds substantial behavioral context beyond the annotations: it discloses the pricing units, minimum charge, VAT treatment, and the special case where a KP API key causes the customer's plan to pay. Annotations already cover safety and idempotency, so this added billing behavior is the main value here.

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 two sentences and front-loads the pricing formula. It is dense but every clause contributes useful information, with no obvious filler.

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 read-only, non-destructive tool with full schema coverage and no output schema, the description sufficiently explains what the returned quote represents and how it is calculated. It does not describe error states or quote expiration, but those are secondary for this tool's complexity.

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 coverage is 100%, and both parameters are already documented in the schema. The description adds context about what the returned price applies to (ready, unpaid files) but does not add syntax or meaning for the parameters themselves.

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 that the tool returns the price of a job's ready, unpaid files, and explains the pricing formula. It is specific about the resource and computation but does not explicitly distinguish its role from sibling tools like create_payment_link.

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?

There is no explicit guidance on when to call this tool versus alternatives such as create_payment_link or get_preview. The billing formula implies it is used to determine cost before payment, but the description leaves that inference to the agent.

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