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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful non-annotation context — the 10-credit Tier 1 cost and the tradition grouping — but says nothing about what the computation returns or any constraints on the input chart.

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?

Two short, front-loaded lines with structured bracketed metadata; nothing is padded. It is efficient, though the brevity edges toward under-specification rather than optimal density.

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 annotations cover safety. However, for a 15-parameter chart-computing tool the description should at minimum clarify that it consumes birth data and what distinguishes its output from the sibling Brennan/Hellenistic tools — that gap is unfilled.

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 33% across 15 parameters, and the description contributes zero parameter information. The four required inputs and the numerous optional chart/formatting flags (zodiacType, houseSystem, cosmogram, name, city) are left entirely to the schema, which documents only a handful of them.

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 concept ('Classical planetary joys') and gives a concrete example mapping ('Sun-Leo-9th'), but it never states what the tool actually does — return a static reference table or compute the joys for the supplied birth data. The required chart parameters (date, time, latitude, longitude) sit in tension with the table-like example, leaving the action ambiguous. It also does not distinguish itself from the many sibling hellenistic_brennan tools.

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 when-to-use guidance, no prerequisites, and no named alternative. The '[Group: Hellenistic: Brennan tradition]' tag hints at a family of related tools but gives no condition for choosing this one over, say, triplicity_rulers or lots_15.

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