月末締め日情報

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

The description discloses the key logic of moving the closing date forward if the month-end is a holiday. However, with no annotations, it leaves important behavioral details unclear: how holidays are determined (weekendDays vs customHolidays), whether the effective date is always returned or only when a holiday occurs, and what happens if the moved date also falls on a holiday. This is a moderate transparency gap.

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 a single, concise sentence that conveys the core functionality immediately. There is no filler or redundant phrasing; it is appropriately sized for the tool's complexity.

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?

Without an output schema, the description should clarify the return structure, but it does not. The conditional wording makes it ambiguous whether the output always includes both the month-end date and the effective date, and there is no mention of edge cases like consecutive holidays. Combined with no annotations, the description is not fully self-sufficient for an agent to predict the tool's behavior.

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% for all three parameters (yearMonth, weekendDays, customHolidays), so the baseline is 3. The description adds no information about parameter usage or formats beyond what the schema already provides, so no score adjustment is warranted.

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: it returns the last day of the specified month and, if that day is a holiday, the adjusted closing date moved earlier. The verb '返します' is specific and the resource is distinct from siblings like is_business_day or list_holidays, which focus on other date calculations.

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?

No guidance is provided on when to use this tool over alternatives. There is no mention of scenarios where this is preferred, no exclusion criteria, and no comparison with sibling tools. The description only explains what it does, not when to invoke it.

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