Chinese Element

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds genuinely useful operational context absent from the annotations: the POST endpoint path, the 10-credit Tier 1 cost, and the required parameter. It says nothing about error behavior, tolerance for out-of-range dates, or how the result differs when `time`/`timezone` shift the solar-year boundary.

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 front-loaded sentence followed by compact bracketed metadata (group, endpoint, required param, cost). Efficient, though the core sentence is jargon-dense and would benefit from a plainer restatement.

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 annotations cover the safety profile. Still, for a six-parameter tool, the description does not resolve the `date` vs `solarYear` question or the role of `time`, which is the main thing an agent could get wrong.

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 33% (only `timezone` and `timezoneOffset` are documented). The description mentions 'solar year' but never explains how that relates to the required `date`, whether `solarYear` overrides it, or what `time` and `language` do. It fails to compensate for the coverage gap.

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 the resource and the three outputs (fixed-branch element, cycling-stem element, yin/yang), so the purpose is inferable, but it never uses a verb like 'compute' or 'return' and the phrase 'for given solar year' conflicts with the required `date` parameter, leaving the actual input basis ambiguous.

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?

No statement of when to use this over the many nearby siblings (astroway_chinese_zodiac_animal, astroway_bazi_year_pillar, astroway_bazi_element_balance), nor any prerequisites or exclusions. The agent must guess from the name alone.

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