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

Annotations supply the safety profile (non-destructive, idempotent, open-world), so the bar is lower, and the description still adds the essential behavioral fact that the call costs a flat $0.05 — a charging trait not captured by any annotation. It does not detail the payment flow, but the x_payment parameter schema already explains the charge/quote behavior.

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?

Two short sentences, front-loaded with the resource and scope, with the pricing fact trailing. Every clause earns its place; no 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?

With an output schema present, return values need not be explained, and annotations cover the safety profile, so the description needs only purpose and pricing — both delivered. The one gap is the absence of sibling routing guidance for a tool that overlaps heavily with jp_payroll_net and jp_social_insurance.

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% across all 7 parameters, including the age-gated rules and payment header, so the schema carries parameter semantics fully. The description only adds the parenthetical '(+bonus)', which slightly anticipates the annual_bonus_yen parameter but adds little beyond the schema.

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?

States a specific resource (Japan payroll) and enumerates what it computes: net salary, social insurance, income walls, and bonus. The phrase 'in one call' hints it consolidates the sibling calculators (jp_payroll_net, jp_social_insurance, jp_bonus_net), but it never names them, so the differentiation from those siblings is left implicit.

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?

'in one call' implies this is the combined/all-in-one option versus the single-purpose siblings, which is a usable hint. However, there is no explicit when-to-use or when-not-to-use guidance, and no statement that it should be chosen over jp_payroll_net when the full breakdown is wanted.

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