Calculate Saju (Four Pillars)

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

With no annotations, the description fully describes the output: pillars (with hanja), element distribution, Day Master, and zodiac animal. It also notes that input must be a solar birthdate, a key behavioral constraint. The description is transparent about what the tool returns, though it omits details like required permissions or rate limits (likely irrelevant).

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 consists of two succinct sentences: the first states the action and input, the second lists the outputs. Every word serves a purpose, and the structure is front-loaded with the key verb and resource.

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?

Given the 6 parameters and no output schema, the description adequately covers the return values and the critical 'solar birthdate' requirement. It lacks information about error handling or edge cases (e.g., invalid date), but for a calculation tool that's acceptable. The completeness is high for the complexity level.

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 description does not need to add parameter details. It mentions output components but does not clarify parameter semantics beyond the schema. For instance, the effect of gender on 'luck-pillar direction' is noted in the schema but not reinforced in the description. Baseline 3 is appropriate.

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 verb 'Compute' and the resource 'Korean Four Pillars of Destiny' from a solar birthdate. It lists the outputs, making the purpose unambiguous. However, it does not explicitly differentiate from sibling tools like saju_compatibility or saju_interpret, which would require an additional sentence to achieve a 5.

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?

The description provides no guidance on when to use this tool versus its siblings (saju_compatibility, saju_daily, saju_interpret). It does not mention prerequisites, contexts, or exclusions. The agent must infer usage 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.