日本の祝日一覧

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

Annotations already declare readOnlyHint=true, and the description adds that the list includes substitute holidays and national holidays, plus the supported year range. This goes beyond the annotation by specifying scope and inclusion criteria, which helps the agent understand exactly what will be returned.

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 short, front-loaded sentences with no redundancy. It efficiently conveys the main action, additional inclusions, and the valid range.

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 read-only holiday list tool, the description fully covers the input scope, output, and constraints. The annotations handle safety, and the schema covers parameters, so no further context is needed.

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 100% with clear descriptions for both year and month, so the description adds little beyond what the schema already provides. It does reinforce that month is optional via 'or year/month', which is already evident from the schema's required field list.

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 'returns a list of Japanese holidays for the specified year (or year/month)', using a specific verb and resource. It distinguishes itself from siblings like jp_next_holiday by focusing on listing holidays for a given period rather than finding the next holiday.

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 provides clear context on what the tool does and its supported range (2020-2099), making the use case obvious for holiday list retrieval. However, it does not explicitly mention alternatives or when not to use it, such as pointing to jp_next_holiday for single-next-holiday queries.

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