Month Pillar

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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so the safety profile is covered. The description usefully adds pricing (10 credits, Tier 1) and the fact that boundaries follow solar terms rather than calendar-month starts, but it says nothing about authentication, determinism of the result, or error conditions beyond the generic schema constraints.

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?

Very compact and front-loaded: the substantive statement comes first, followed by scannable bracket fields for group, endpoint, required param, and cost. The fragment style is terse rather than wasteful, though the endpoint line has little value to an agent that cannot issue raw HTTP calls.

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 5-parameter tool with an output schema and only 40% schema coverage, the description should clarify how the optional date/time/timezone/language inputs interact with solar-term boundary calculation. It covers purpose and cost but leaves an agent unable to know whether supplying a time changes the result — a meaningful gap for a boundary-sensitive calculation.

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 only 40%: only timezone and timezoneOffset are documented in the schema, while date, time, and language carry no description. The description contributes only "[Required: date]", which merely restates the schema's required list, and it never explains whether time/language/timezone shift the solar-term boundary and thus the computed pillar.

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?

"Month stem + branch from solar-term boundaries" names the specific resource (BaZi month pillar) and the computation basis, which is more than a restatement of the name. It does not, however, distinguish itself from close siblings like astroway_bazi_monthly, astroway_bazi_four_pillars, or astroway_bazi_year_pillar/hour_pillar, so an agent must still guess which BaZi tool to pick.

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 when-to-use guidance at all — nothing says whether to call this alone, versus in combination with astroway_bazi_four_pillars or astroway_bazi_chart. The bracketed metadata only states the required parameter and cost, not the selection conditions against the many BaZi siblings.

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