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

With no annotations, the description carries the behavioral burden. It does disclose the per-call cost (每次 ¥0.05) and the general nature of the output (命理解读), which is useful. It does not mention side effects, authentication, rate limits, or response format, but for a simple reading tool the cost disclosure adds meaningful transparency.

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 two short sentences with no filler. It front-loads the core purpose, then gives usage and pricing in minimal space. Every sentence contributes essential information.

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?

For a one-parameter tool with an output schema, the description covers the main requirements: what the tool does, what input is expected, and what it costs. The main gap is the lack of differentiation from the closely related bazi_quick sibling, which could affect tool selection.

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?

The schema provides no description for the required q parameter, so the description must compensate. It does so by defining q as a keyword and giving concrete examples (紫微/命宫). This makes the parameter actionable despite 0% schema coverage.

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 resource (紫微斗数命盘) and the action (解读), and notes that the user supplies a keyword to receive a fortune-interpretation result. It is not a tautology and would be recognizable as a distinct Ziwei tool, but it does not explicitly distinguish itself from sibling bazi_quick.

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: input a keyword like 紫微 or 命宫 and get an interpretation. However, it gives no explicit guidance on when to choose this tool over bazi_quick or other siblings, and no exclusion conditions or prerequisites are provided.

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