24 Solar Terms (節氣)

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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the description's job is supplementary — and it delivers the response shape (exact instants in UTC and Beijing time) plus the endpoint and a 10-credit Tier 1 cost, which matters for call budgeting. It does not mention failure modes or what happens at the schema's edge years, so it stops short of a 5.

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 two descriptive sentences are front-loaded and every clause carries information; the bracketed metadata block is terse and useful rather than filler. Slightly more boilerplate (group/endpoint lines) than strictly needed for selection, but it does not bury the substance.

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?

An output schema exists, so return values need no explanation, and the annotations cover safety. For a simple one-required-integer tool the description supplies timezone, domain meaning, and cost. The remaining gap is the undocumented 'language' 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 description coverage is 0%, so the description carries the burden. It confirms 'year' is required and contextualizes it as a Chinese solar year, but says nothing about the second parameter ('language', an unconstrained string with no schema description) or the valid 2–2899 year range. Roughly half the parameters remain unexplained in both places.

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 resource ('The 24 solar terms of a Chinese solar year') and what is returned ('exact instants, in UTC and Beijing time'), with the additional detail that twelve open a BaZi pillar month and twelve determine leap-month placement. That is enough to distinguish it from siblings like astroway_chinese_lunar_date or the astroway_bazi_* tools without opening the schema, though no sibling is named explicitly.

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 only implied: the BaZi pillar-month and leap-month clauses hint at when this data is needed, and the 'Required: year' note scopes the call. There is no explicit when-to-use statement, no exclusion, and no pointer to an alternative (e.g. lunar_date vs. solar terms).

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