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

Goes beyond the annotations by disclosing cost ($0.01/call), determinism, sourcing (cites primary sources), and the billing policy that errors and unverified rules are never charged. That is genuinely useful context an agent cannot infer from readOnlyHint/idempotentHint alone, and it explains why readOnlyHint=false for what looks like a pure calculation.

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 sentences, purpose front-loaded, and the second sentence packs cost, determinism, and the error-billing policy without padding. Slightly fragmentary phrasing but no wasted content.

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?

An output schema exists so return values need not be described, and all parameters carry schema descriptions. The main remaining gap is routing guidance against the many jp_* payroll and tax siblings, which the description does not address.

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 the schema already documents all eight parameters in detail. The description only adds the link between the withholding lookup and previous month salary, which is marginal value over 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?

Names a specific resource and computation: net bonus pay, broken into social insurance and withholding tax, with the rate-table basis stated. An agent can tell it apart from jp_payroll_net by the bonus scope, though no sibling is explicitly named.

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 when-to-use, when-not-to-use, or alternative selection guidance. The parenthetical '(based on previous month salary)' hints at a prerequisite but the description never says to use jp_payroll_net for ordinary salary or jp_social_insurance for standalone SI lookups.

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