jp_to_wareki

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

With no annotations, the description carries the full burden of behavioral disclosure. It adds meaningful detail by stating that era boundaries are handled to the day, which is a key precision guarantee. However, it does not specify the return format (e.g., whether it includes the Japanese year number or just the era), nor does it address edge cases like dates before the Meiji era. This is adequate but incomplete for full 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 a single, concise sentence that immediately states the action and target format. It also adds a valuable precision note without any filler. Every element earns its place, and the structure is front-loaded with the verb.

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 is a simple one-parameter converter with no output schema, the description explains the conversion and the era boundary guarantee, which covers the core behavior. It falls short of full completeness because it omits the exact return format and edge-case handling, but for a conversion tool of this complexity, it is sufficiently complete for an agent to invoke it correctly.

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 for the single 'date' parameter with a format description (YYYY-MM-DD). The description adds the term 'Gregorian' which clarifies the calendar system, but this is a minor addition. Since schema coverage is high, a baseline of 3 is appropriate; the description does not introduce new constraints or details 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 clearly states the tool converts a Gregorian date to Japanese imperial era format, with a specific verb ('convert'), source ('Gregorian date'), and target ('Japanese imperial era format'). It lists the era names, and the direction is unambiguous. It also distinguishes itself from the sibling jp_from_wareki by the conversion direction.

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: use this to convert Gregorian dates to wareki, and notes that era boundaries are handled precisely. It does not explicitly mention alternatives or exclusions, but the sibling set implies the reverse tool jp_from_wareki would handle the opposite direction. The guidance is implied rather than explicit, so it just misses a 5.

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