getCoupons

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

Annotations already indicate readOnlyHint=true, destructiveHint=false, idempotentHint=true. The description adds the context that only non-deleted coupons are returned and lists the fields included, providing behavioral insight beyond annotations without contradiction.

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 concise with four sentences, each adding value: purpose, parameter requirement, returned fields, and sibling tool references. No redundant or unnecessary information.

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 lists key fields and explains coupon_type values. It covers the essential aspects of what is returned and filtering, though pagination or ordering are not mentioned, but for a full-list retrieval tool, this is sufficient.

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 has a single dummy parameter with description 'Not used', and the description states 'クエリパラメータは不要' (query parameters not needed), confirming no functional parameters. With zero meaningful parameters, the description adds clarity above 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 it retrieves the list of all non-deleted coupons. It uses the specific verb '取得します' (retrieve) and specifies the resource 'クーポンの一覧'. It also distinguishes from sibling tools like getCoupon, createCoupon, updateCoupon, deleteCoupon.

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 explicitly states that no query parameters are needed and returns all coupons. It provides direct guidance on when to use alternative tools: getCoupon for a specific coupon, createCoupon for creation, etc., making usage boundaries clear.

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