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

No annotations are provided, so the description carries the burden. It helpfully discloses the return contents (the three prize categories and the claiming period), which is real behavioral context, but says nothing about read-only nature, rate limits, or data recency beyond the implied 'latest period'.

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?

One tightly packed sentence with the resource front-loaded. The bracketed tag prefix ［台彩 發票 油價對獎］ is somewhat noisy boilerplate but does not obscure the core statement.

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 single-parameter, read-only lookup with no output schema, the description tells the agent what will be returned and that a claiming period is included. Adequate, with the only meaningful gap being sibling disambiguation.

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 description coverage is 100% for the single optional 'period' parameter, whose format example (115-05-06) and default behavior are already documented in the schema. The description adds nothing beyond that, so the baseline 3 applies.

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?

States a specific verb (取得) and resource (台灣統一發票中獎號碼), and even enumerates the prize tiers returned (特別獎、特獎、頭獎) plus the claiming period. It is clear what the tool does, though it does not explicitly differentiate itself from the nearby sibling life__check_invoice.

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?

There is no guidance on when to use this tool versus alternatives. The sibling life__check_invoice likely covers the 'did my invoice win' case, and the description never clarifies whether this tool merely lists winning numbers or supports checking, leaving the agent to infer the split.

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