Western Zodiac Compatibility

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

Annotations already cover read-only, idempotent, non-destructive behavior. The description adds useful context beyond that: no ephemeris calculation, fast execution, basis in element/modality affinity, and a link to the full output/error contract. It would only reach 5 by describing error cases inline rather than referencing a docs URL.

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 front-loaded with the core purpose and uses clear labeled sections (WORKFLOW, INPUT CONTRACT, DO NOT CONFUSE WITH) that make scanning easy. Every section earns its place; no filler or tautology.

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 an output schema present and annotations covering safety/idempotency, the description supplies the missing behavioral and routing context: prerequisites, alternatives, underlying logic, and a pointer to the full contract. Nothing an agent needs to select and call this tool correctly is missing.

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?

Input schema coverage is 100%, so the schema already documents sign1, sign2, and response_format with examples and defaults. The description's INPUT CONTRACT mostly restates parameter names without adding semantic detail 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 states a clear resource ('sign-to-sign compatibility') and methodology ('element and modality affinity'), and immediately distinguishes it from similar-sounding siblings. It names exactly what this tool is not: asterwise_get_western_compatibility and asterwise_get_western_synastry.

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?

Explicit WORKFLOW and DO NOT CONFUSE sections tell the agent when to use this tool vs alternatives: no birth data needed, use asterwise_get_western_compatibility when full charts are available, and use synastry for aspect geometry. This is textbook-level routing guidance.

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