Compute a deterministic BaZi (八字) / Korean Saju (사주) Four Pillars chart from a solar birth date: Heavenly Stems, Earthly Branches, Day Master, and five-element distribution. KASI-validated engine, no AI.
| Name | Required | Description | Default |
|---|---|---|---|
| day | Yes | ||
| hour | No | 0–23, or -1 if birth time unknown | |
| year | Yes | 1920–2050 | |
| month | Yes | ||
| gender | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It adds behavioral context by stating 'deterministic' and 'KASI-validated engine, no AI', but lacks details on error handling, side effects, or rate limits.
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 a single, front-loaded sentence that efficiently conveys the tool's purpose without unnecessary words.
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?
There is no output schema, so the description should detail return values. It lists components but not their format. Parameter details are lacking, and no comparison with the sibling tool is provided.
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 low (40%). The description mentions 'solar birth date' but does not explain individual parameters like hour (0–23 or -1), gender (M/F), or the year range. It adds little beyond the schema definitions.
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 states a specific verb 'compute', the resource 'BaZi chart', and lists output components (Heavenly Stems, Earthly Branches, Day Master, five-element distribution). It clearly distinguishes from the sibling tool 'bazi_compatibility'.
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 implies usage for computing a BaZi chart from a solar birth date, but does not explicitly state when to use this tool vs. the sibling 'bazi_compatibility' or provide any exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
The two tools have clearly distinct purposes: bazi_chart computes a single person's chart, while bazi_compatibility evaluates compatibility between two people. No overlap in functionality.
Both tools follow a consistent 'bazi_' prefix with underscore-separated descriptive nouns (chart, compatibility), forming a clear and predictable naming pattern.
With only 2 tools, the server feels slightly thin for a full 'Four Pillars' server, though it covers core chart computation and compatibility. A typical server of this scope might include 3-5 tools.
The server lacks tools for interpreting the chart, analyzing element relationships, or providing detailed profiles beyond the raw chart and a compatibility score. This leaves significant gaps in the expected lifecycle.