Arabic Parts (Lots)

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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is settled. The description adds genuinely useful non-schema context — the response contains standard lots plus any custom formula, and the call costs 20 credits (Tier 2) via POST /v1/arabic-parts. It says nothing about lot-set size, custom formula syntax, or limits.

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 sentences front-load what is computed and what is returned; the group/endpoint/cost lines are terse metadata, with the cost line earning its place for billing awareness. No filler.

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 and the input schema is richly annotated, so return values and parameters need no prose. What is missing is selection context: which lot set is used and how this differs from the sibling lots tools, which is the main open question for an agent in this catalog.

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 100% and the nested 'body' schema already explains birth data, timezone handling, ayanamsa and house system at length. The description only gestures at the 'parts' array via 'any custom formula', which the schema itself documents more precisely. Baseline 3 is correct when the schema carries the load.

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 ('Arabic parts (Lots)') scoped 'from a natal chart', and adds that standard lots plus custom formulas come back. It does not, however, distinguish itself from the many overlapping sibling tools (astroway_hellenistic_brennan_lots_15, astroway_hellenistic_hand_lots_of_seven, astroway_vedic_kp_fortuna), which an agent would need in order to choose.

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?

No when-to-use, when-not-to-use, or alternative is named. The only usable signal is the implicit 'needs a natal chart' framing, and the large family of lots-oriented siblings is left unaddressed.

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