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

The description adds valuable non-annotation context: $0.02/call pricing, determinism, citation of primary sources, exact rounding behavior, and a guarantee that errors/unverified rules are never billed. These details go beyond the annotations and help an agent set expectations for cost and reliability. There is no contradiction with the annotation flags.

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 with no filler. The domain and core rules are front-loaded, followed by cost and reliability facts. Every clause earns its place and supports tool selection and invocation.

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 selection and invocation, the description covers purpose, cost, reliability, and key domain behaviors, while the schema covers parameters and the payment handshake. However, with no output schema, the description does not explicitly state what the result contains beyond hinting at primary-source citations, leaving a moderate gap in the return contract.

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 every parameter. The description adds domain context for years_of_service and payout_yen via the deduction/half-taxation framing, but it does not add meaning for x_payment, disability, or is_officer beyond what the schema already says. This is the expected baseline when the schema carries the parameter details.

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 identifies the tool as the Japanese retirement income tax calculation and lists concrete behaviors: deduction by years of service, half-taxation rules, and exact withholding rounding. This separates it from bonus, payroll, and social-insurance siblings, though it lacks an explicit verb like 'calculates' and does not name a comparison sibling.

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 use case is implied by the title and opening phrase 'Retirement income tax', so an agent can infer when to choose this tool. However, it gives no explicit guidance about when not to use it or which sibling alternative might be more appropriate for related scenarios.

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