次の五十日を計算

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

The description discloses a key behavior: if the calculated date is a holiday, it also returns the date adjusted to the previous business day. However, it does not specify the return structure, recursion of adjustments, or edge cases. With no annotations provided, this is moderate but incomplete transparency.

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 concise sentences, front-loading the core functionality followed by the adjustment behavior. No redundant or ambiguous wording, making it appropriately sized.

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 no output schema and moderate complexity, the description does not fully explain the return value format, which is critical for agent usage. It also omits how weekendDays and customHolidays parameters affect the calculation, though the schema covers these. The core concept is clear, but operational details are missing.

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?

The input schema already provides 100% coverage of all three parameters with descriptions and examples. The tool description adds no additional parameter semantics, so the baseline score of 3 applies.

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 the tool's function: returns the nearest Go-tobi (5th, 10th, 15th, 20th, 25th, month-end) on or after a specified date. It distinguishes this from sibling tools by introducing the specific Go-tobi concept and the holiday adjustment behavior.

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 does not explicitly state when to use this tool versus alternatives. It implies usage for Go-tobi calculations but provides no guidance on choosing it over siblings like month_end_info or is_business_day, nor does it mention any exclusions.

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