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

With no annotations provided, the description carries the full behavioral burden. It identifies the operation as a retrieval (取得) and the grouping basis, but says nothing about permissions, pagination, whether an empty month returns an empty list, or how results are ordered beyond the vague 依官方發售時期.

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?

A single, front-loaded sentence with no filler, appropriately sized for a simple two-parameter read tool. It is efficient, though the brevity borders on under-specification given the gaps elsewhere.

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?

With no output schema, no annotations, and half the parameters undocumented, the description should explain the return shape and the brand filter's role. It does neither, leaving an agent unable to predict what a call yields or how to use the optional parameter.

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 only 50%: month has a format description (YYYY-MM) but brand is an enum with no explanation. The description implies a month scope but never mentions the optional brand filter, its default, or whether omitting it returns all brands.

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 concrete verb (取得) and resource (扭蛋與公仔發售表), plus the scope (某個月, 依官方發售時期), so an agent knows this returns a monthly gashapon/figure release schedule. It does not, however, distinguish itself from siblings like search_toys or latest_toy_news that could also surface release information.

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 explicit statement of when to use this tool versus search_toys, latest_toy_news, or toy_stats. The phrase 依官方發售時期 hints at the ordering basis but gives no conditions for selection or exclusion relative to alternatives.

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