Horary Chart

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond them: it names the analytical payload (radicality, significators) and discloses the billing tier and credit cost, which the annotations do not carry. No auth, rate-limit, or latency context.

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?

One front-loaded sentence stating purpose and output, followed by compact bracketed metadata for group, endpoint, required fields and cost. Nothing is padded, though the required-fields line duplicates the schema's required array.

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?

For a 13-parameter astrological calculation, the description leaves the optional but outcome-changing settings (houseSystem, zodiacType, ayanamsa, cosmogram) completely unexplained. An output schema exists so return values need no explanation, but the input-side gaps and the missing differentiation from sibling horary tools are serious for a tool of this complexity.

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 23% across 13 parameters, so the description must compensate and it does not — it only restates the four required fields already marked required in the schema. Critically, the houseSystem parameter is a bare enum of single letters (P, K, R, C...) and the description gives no hint about defaults or meaning.

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 specific verb ('Calculate') and resource ('horary chart'), plus what the response contains (radicality assessment, significator analysis). It does not differentiate itself from the many horary siblings (astroway_horary_diagnostics, _moon_aspects, _via_combusta, astroway_vedic_kp_horary), so an agent cannot tell from the description alone why to pick this one.

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?

'for a question moment' implies the horary use case — the chart is cast for the instant a question is asked — which is useful implied context. However, there is no explicit when-to-use/when-not, no prerequisites, and no pointer to the sibling horary tools that handle narrower slices.

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