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

With no annotations, the description must carry the burden, and it does so well by disclosing determinism, Meeus-based astronomical calculations, true-solar-time correction, historical Korea timezone awareness, and structured JSON output. It doesn't mention error handling or edge cases, but for a compute tool the disclosed behavioral traits are sufficient.

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 exactly two sentences, tightly packed with essential information, and leads with the core function. There is no redundancy or fluff; every phrase adds value.

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 tool's complexity and absence of an output schema, the description does a solid job of summarizing key return categories (pillars, elements, ten gods, sinsal, luck cycles) and the methodological nuances. It could be more explicit about output structure or potential errors, but the schema handles parameter constraints, making this adequate.

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?

All 9 parameters already have detailed schema descriptions (100% coverage), so the baseline is 3. The description's mention of true-solar-time correction and timezone awareness adds some context, but much of this is already embedded in the schema (e.g., longitude description explicitly mentions the correction). Thus, the description does not significantly enhance parameter meaning beyond the schema.

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 it computes a Korean Saju chart from birth date/time, listing specific outputs (pillars, five elements, ten gods, sinsal, luck cycles) and methodology. The verb 'Compute' paired with the resource 'Korean Saju' makes the purpose unambiguous, and it distinguishes itself from generic astrology tools through the detailed methodology.

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?

Since there are no sibling tools, explicit alternatives are not needed. The description establishes clear context for when to use this tool—any time a deterministic, astronomically corrected Saju chart is needed—and implies it is the correct choice for such computations. It doesn't explicitly state exclusions or prerequisites, but the coverage is adequate given the absence of competing tools.

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