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 two genuinely useful behavioral facts not in annotations: the tradition group (Hellenistic: Greenbaum) and the cost (10 credits, Tier 1). It adds nothing about computation inputs, failure modes, or rate limits, but with annotations carrying the safety burden a 3 is warranted.

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 text is short and front-loaded, and the bracketed metadata lines are easy to scan. However, the brevity is under-specification rather than disciplined conciseness: there is no sentence that explains purpose, usage, or behavior, so the size reflects missing content rather than efficient writing.

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-value explanation is not required, and annotations cover safety. But for a 15-parameter chart computation with 33% schema coverage and multiple near-identical sibling tools (antiscia, contra-antiscia, aspects_antiscia), the description leaves the agent unable to tell what distinguishes this computation or how to supply the undocumented inputs.

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?

With 15 parameters and only 33% schema description coverage, the description carries an obligation to compensate for the undocumented parameters, and it supplies none. The schema does document a few key params (fields, ayanamsa, timezone, precision, timezoneOffset), but the required date/time/latitude/longitude and several others remain unexplained, and the description adds no syntax or format guidance.

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 is essentially a restatement of the title 'Contra-Antiscia' with an 'Equinoctial' qualifier. It names the astrological resource but gives no verb (compute/derive) and never explains what contra-antiscia are or what the tool returns, so it is near-tautological against the name/title. The alias note identifies equivalence with the long-named sibling but does not distinguish this tool from astroway_aspects_antiscia or astroway_helg_antiscia_hellenistic.

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 at all. The only routing information is that this is a 'cursor-friendly alias' for astroway_hellenistic_greenbaum_contra_antiscia, which implies interchangeability but does not tell the agent when to prefer this over that sibling or over the antiscia variants. No prerequisites or exclusions are stated.

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