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 usefully adds that the horary moment is the call moment (no separate moment argument) and discloses the cost (20 credits, Tier 2), which is real behavioral context beyond the annotations.

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 tight sentences with the output and the key input front-loaded, plus compact Group/Cost tags. No filler; nothing is buried.

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 spelled out, and annotations cover safety. However, for an 11-parameter tool at 45% coverage, the description is thin on how the moment and ayanamsa inputs interact with the horary number, and it gives no KP-specific defaults.

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 45%; six parameters (date, time, latitude, longitude, horaryNumber, ayanamsaId) carry no schema description. The description only conceptually ties horaryNumber to the 1..249 range and gestures at the moment params, leaving ayanamsa default, timezone handling, and precision undocumented.

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 verb and resource: a KP horary number lookup that returns the canonical KP-table ASC longitude plus sub-lord chain. It is clear what the tool produces, but it never differentiates itself from near-neighbors such as astroway_horary_horary or astroway_vedic_kp_asc_sub, which an agent in this crowded sibling space would need.

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?

It states the input precondition (a number 1..249) and clarifies that the horary moment is the call moment, but gives no when-to-use/when-not guidance and names no alternative among the many horary and KP siblings. The agent must infer selection on its own.

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