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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds behavior the annotations cannot: a hard year restriction (2026/2027 only) and an explicit content exclusion for annual event announcements. It does not discuss result formatting or ordering, but with annotations and an output schema in place this is a modest gap.

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 clause-chained sentence with the core purpose first, then scope limits, then the exclusion. Every clause carries distinct information (what, which years, what is excluded) with no restatement of the name or padding.

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?

The tool is simple (one required integer), annotations cover safety, and an output schema exists, so return values need not be explained. The description covers scope and the year restriction, which is most of what an agent needs. Minor gap: '十二月名依据' is left unexplained, so an agent cannot anticipate how that basis is represented in the response.

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 100% and the schema already says the parameter is a Gregorian year integer with an '暂无' result for other years. The description contributes genuinely new constraint information by naming the valid years (2026, 2027), which the schema leaves unspecified. That is real added meaning beyond the schema, though no format or boundary detail beyond the year list.

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 names a specific verb and resource ('按公历年查询已审核正式节日核心日完整表及十二月名依据'), so an agent knows this returns an authoritative festival table keyed by Gregorian year, plus the twelve-month-name basis. It also scopes content ('核心日完整表') versus what it omits ('年度活动公告'). It does not explicitly differentiate itself from the siblings (convert_gregorian_to_tibetan, get_day_mechanism), which keeps it out of 5 territory.

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?

Usage is bounded explicitly: only years 2026 and 2027 are supported, and annual event announcements are out of scope. That gives a clear when-to-use condition and one when-not-to-use exclusion. It stops short of naming an alternative tool for the excluded cases or for other years, so it is not a 5.

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