Yearly Horoscope

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

Annotations already declare readOnly/idempotent/non-destructive and non-open-world, so safety is covered. The description adds genuinely non-structured context: the endpoint, that only 'sign' is required, and that a call costs 100 credits at Tier 4 — cost awareness is important for a paid generative call.

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 followed by compact metadata lines; the call's scope and outputs come first and nothing is redundant. Slight cost: the tag-block format is terse rather than explanatory, but it is efficient.

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 not be described, and cost/endpoint/required-param are supplied. However, for a 7-parameter generative tool with a 12-month window, the description leaves the meaning of 'date', default behaviors, and the effect of 'topics'/'length' on output entirely to the schema.

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 only 43% across 7 parameters, so the description should compensate but does not. It mentions only the required 'sign'; the ambiguous 'date' parameter (start of the year window? natal date?) is never explained, and 'language' and 'disclaimer_inline' get no mention at all.

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 specific verb ('Generate') and resource ('year-ahead horoscope, 12-month window') and enumerates the content produced (transit cycles, solar return context, profection time-lord). The 12-month scope implicitly separates it from the daily/weekly/monthly horoscope siblings, though no sibling is named outright.

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 implied by the time window rather than stated: an agent can infer this is the yearly option versus astroway_horoscope_daily/weekly/monthly. There is no explicit when-to-use, when-not-to-use, or prerequisite statement.

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