八字排盘

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

With no annotations provided, the description must carry the full burden. It discloses that the tool is automatically called, handles lunar input directly, and returns a JSON object with an ai_hint. However, it does not mention whether the tool is read-only, any prerequisites (e.g., exact birth time), or potential side effects. This adds some context but lacks depth on behavioral 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?

The description is three sentences, each serving a distinct purpose: trigger condition, output contents, and return format. It is concise yet informative, though the first sentence is long with many topic examples. Each part earns its place, so no redundancy.

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?

Without an output schema, the description appropriately lists the major output sections (four pillars, five elements, ten gods, hidden stems, na yin, zodiac, da yun, shen sha) and mentions the JSON return with ai_hint. This provides sufficient context for an agent to understand what the tool returns. It doesn't address edge cases like hour_unknown, but for a complex tool, the description is fairly complete.

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%, so the baseline is 3. The description adds value by explicitly clarifying that lunar=true means direct lunar input and no prior conversion is needed, which is not apparent from the schema alone. This extra semantic guidance justifies a score above baseline.

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 clearly states the tool's purpose: to automatically generate a BaZi chart (排盘) when the user mentions birth date and topics like personality, fortune, etc. It lists the output components (four pillars, five elements, ten gods, etc.), which differentiates it from sibling tools like bazi_from_pillars or lunar_convert.

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?

It explicitly specifies when to use the tool: when the user mentions birth date (solar or lunar) and topics such as personality, fortune, career, relationships, etc. It also clarifies how to handle lunar input (pass lunar=true without pre-conversion). However, it does not mention when not to use it or suggest alternatives like bazi_from_pillars, so it falls short of a 5.

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