Animal Compatibility

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

Annotations already declare readOnly/idempotent/non-destructive, so the description's contribution is cost tier (10 credits, Tier 1), the POST endpoint, and the scoring basis and output range — genuine behavioral context beyond the annotations. It does not say how the two persons' inputs are reduced to animals or what happens on invalid dates, leaving a small gap.

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 core sentence is front-loaded and the bracketed metadata lines are short and scannable. Nothing is padded, though the group/endpoint lines are boilerplate rather than information the model needs to select or call the tool.

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?

An output schema exists so return values need no explanation, and cost plus required inputs are given. However, for a tool with two nested person objects and a non-trivial timezone/time surface, the description does not say how much of that nested input actually matters for a zodiac pairing score — the single largest gap for correct 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?

Schema description coverage is 0% at the top level, so the description must compensate and largely does not: the only parameter content is '[Required: person1, person2]', which merely restates the schema's required array. It never explains the nested person structure (date required, optional time, language, timezone handling) even though the presence of a time field raises the question of whether the hour pillar affects the pairing.

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?

States a concrete verb+resource: computes a 0-100 pair compatibility score for Chinese zodiac, and names the scoring canon (San He trine + Liu Chong) which differentiates it from other compatibility siblings such as astroway_mayan_compatibility or astroway_vedic_compatibility_ashtakoot. It never names those alternatives explicitly, so the differentiation is implicit rather than stated.

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?

Usage is only implied by the resource name and the [Required: person1, person2] line; there is no statement of when to choose this over the many other compatibility tools in the catalog, nor any prerequisite or exclusion. The [Cost: 10 credits (Tier 1)] line does add a useful operational consideration an agent can weigh.

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