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

The description adds significant behavioral context by detailing the complexity and depth of the expected output (e.g., 'deity, star, door, heaven/earth/hidden stems'). This informs the agent that the tool performs deep analysis, going far beyond simple structural execution.

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 tool definition is packed with necessary technical detail, but it is presented as a single, extremely long run-on sentence. While efficient in information density, it lacks structural clarity.

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 that no output schema exists, the description is exceptionally complete. It outlines every major component that an agent must expect in the response, making it a complete guide for both selection and invocation.

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?

Although the schema provides 100% coverage, the description provides critical semantic meaning for the `focus` parameter, clarifying that selecting a focus 'changes palace scores and lucky directions,' thereby explaining the impact of the input on the analysis.

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 is highly specific, stating exactly what is cast (Qi Men Dun Jia chart) and listing all constituent elements of the result, such as 'four pillars,' 'ju,' and 'palace scores.' This leaves no ambiguity for the agent.

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?

While it doesn't offer a formal 'when/when-not' rule, the exhaustive list of output components implies that this tool is intended for the comprehensive, full-fidelity analysis of the chart, distinguishing it from a simpler tool that might only return 'pillars'.

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