営業日判定

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

With no annotations, the description carries the full burden. It discloses consideration of weekends, Japanese holidays, substitute holidays, and custom company holidays, but omits that the weekendDays parameter can override the default Saturday/Sunday definition and does not state the return type or invalid-date behavior.

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, focused sentence that front-loads the core action and lists the holiday types without redundancy. It is appropriately concise for the tool's simplicity.

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 a simple boolean check tool, the description is largely complete: it specifies the input (a date) and the business-day criteria. However, because there is no output schema, it would be beneficial to explicitly state that the result is a boolean; the current phrasing '判定します' is slightly ambiguous about the return value.

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 schema provides 100% coverage with descriptions for all three parameters, including formats and defaults. The description adds only a general mention of holiday types, not specific parameter semantics beyond 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?

The description explicitly states the tool determines whether a specified date is a business day, using the specific verb '判定します' and clearly scoping to a single date. It also enumerates the holiday categories considered, distinguishing it from sibling tools that perform date arithmetic or list holidays.

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 explicit guidance is given for when to prefer this tool over alternatives; the intended use is only implied by the tool's purpose. There are no exclusions or references to sibling tools like add_business_days, so the agent must infer usage from context.

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