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

Annotations already declare the tool read-only, idempotent, and non-destructive, so the bar for additional disclosure is lower. The description adds useful behavioral context beyond annotations: 'Data only — no interpretation is added' and the exact key naming convention for the result. It does not cover edge cases, but that is acceptable given the annotation coverage.

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 description is two sentences, with the core action and output keys front-loaded in the first sentence and the data-only caveat in the second. Every sentence contributes meaningful information and there is no redundant or filler text.

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 simple read-only computation with robust annotations and full schema coverage, the description is nearly complete. It compensates for the missing output schema by listing the exact result keys and data type. It could have briefly mentioned the birth-data dependency or contrasted with sibling arudha tools, but nothing essential is missing for correct invocation.

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 each parameter already has clear semantics with formats and examples. The description itself adds no parameter-level information beyond the schema. Per the baseline rule, a 3 is appropriate when the schema carries the parameter-documentation burden without gaps.

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 states a specific verb ('Return'), a specific resource ('surya arudhas'), and a precise scope: arudha signs for all 12 houses counted from the Sun (Surya Lagna). It also enumerates the exact output keys. This clearly differentiates the tool from siblings like get_chandra_arudhas and get_graha_arudhas by anchoring on 'from the Sun'.

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?

The description implicitly conveys usage context by defining the tool as data-only and Sun-based, but it never explicitly states when to prefer this tool over alternatives such as get_chandra_arudhas or get_arudha_padas. No exclusions or alternative routing are provided, so an agent must infer usage from the name and phrasing.

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