listEarnCoupons

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

The annotations already declare readOnlyHint and openWorldHint, and the description adds valuable behavior beyond that: returned cards include all states (InUse, NotUse, Expired, AlreadyUsed) and the rate limit is disclosed. It does not contradict the annotations and provides useful non-obvious details.

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 front-loaded with the core purpose and then provides useful supplementary guidance about returned states, downstream usage, endpoints, and rate limits. It is slightly longer than strictly necessary for a one-parameter read-only tool, but every section adds practical value.

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 1-parameter read-only query with no output schema, the description covers the main need: what data is returned, which states are included, how to use the returned fields, and the rate limit. It does not describe response shape or pagination, but the core invocation context is complete.

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 0%, so the description must compensate for the single 'category' parameter. It mentions the enum values in the place-order mapping, but it does not explicitly state that the category selects interestCards vs awardCards or exactly how the parameter filters results. The enum values are self-descriptive, but the parameter semantics could be more direct.

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 identifies a specific verb ('Query') and resource ('user's interest-rate coupons (interestCards) and Dual Assets reward cards (awardCards)'), and clarifies the product-category scope. This clearly distinguishes it from the broader Earn-related tools in the sibling list.

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 gives clear operational context: fetch coupons, then pass awardId and specCode when placing an order, with distinct endpoints for FlexibleSaving and DualAssets. It does not explicitly name alternative tools or state when not to use this one, but the intended workflow is evident.

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