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

With no annotations, the description carries the full transparency burden. It discloses that the tool is deterministic, cites primary sources, never bills for errors/unverified rules, and has a per-call cost of $0.02. This gives agents crucial behavioral context about reliability and pricing. It does not cover rate limits or authentication, but for a paid deterministic analysis tool, the disclosed traits are valuable and exceed baseline expectations.

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 three short sentences, front-loaded with the core purpose, then pricing, then behavioral guarantees. Every sentence earns its place with no fluff. The structure is clear and scannable, making it easy for an agent to quickly grasp the tool's value proposition.

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?

Given the tool has 4 parameters, no output schema, and no annotations, the description should provide more context about expected outputs and parameter semantics. It mentions thresholds but not what results are returned (e.g., threshold values, comparison, advice). Parameter usage is not explained. The description is too sparse for a tool with such low schema coverage, leaving significant gaps for an agent to guess.

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 only 25% (only x_payment has a description). The tool description does not explain parameters like 'year' or 'as_of', which are likely dates. Annual_income_yen is self-explanatory from the name, but the others are ambiguous. Since the schema leaves most parameters undocumented and the description does not compensate, agents will struggle to correctly set inputs.

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 it performs 'income-wall analysis' with specific domains (tax, social insurance, spousal and student-dependent walls). It names the exact thresholds (1.06M/1.30M), distinguishing it from other JP financial tools like jp_social_insurance or jp_tax_calculators. The verb 'analysis' together with the resource (income walls) makes the purpose crisp and unambiguous.

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 description implies when to use this tool (for Japanese income threshold analysis) but does not explicitly state when not to use it or mention alternatives. Sibling tools like jp_social_insurance cover related topics, but no comparison or exclusion is provided. The usage is understandable from context but lacks explicit guidance on selection among similar tools.

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