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

No annotations are provided, so the description carries the full burden. It explains the comparison geometry (±45° sectors) but says nothing about what constitutes 'white tiger lifting its head' (i.e., which side being higher is inauspicious), what the response looks like, or what happens with a malformed skyline that isn't exactly 360 bins.

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?

A single front-loaded sentence that establishes the check, its data source, and the comparison in one pass. The parenthetical Chinese term is justified for domain recognition; no filler.

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?

With no annotations and no output schema, the description must explain what the result means, and it does not — an agent cannot tell whether it receives a boolean, an angle delta, or a verdict. For a domain-specific analytic tool this is a substantial gap.

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 both parameters are already documented. The description adds useful framing — that skyline_360 is DEM-derived and that only ±45° sectors around the sitting direction are used — but does not add format or validation detail beyond the schema. 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 names a specific analysis (comparing right/white-tiger vs left/azure-dragon sector elevations) and the data source (a DEM-derived 360-bin skyline). It is far more specific than a restatement of the name, though it stops short of saying what the 'check' produces. Siblings (calendar, flying_star_chart, ganzhi) are unrelated, so no differentiation is required.

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?

There is no explicit statement of when to use this tool versus alternatives, nor any prerequisites beyond the implicit need for a DEM-derived skyline. Usage can be inferred from the feng shui context but nothing routes the agent.

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