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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description's one genuine addition is the cost disclosure (20 credits, Tier 2) plus the Vedic grouping, which are not in the schema or annotations and matter for a paid tool. It still says nothing about output form, precision defaults, or error behavior, so it is adequate-but-thin against the annotation baseline.

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 short sentences plus structured [Group] and [Cost] tags, front-loaded with the resource identity. Nothing is padded; it is efficient, though the terseness is a symptom of under-specification rather than economy of expression.

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 explained, and the annotations cover safety. However, for a 15-parameter chart tool sitting among ~16 near-identical varga siblings, the description omits sibling disambiguation and any parameter guidance, leaving clear gaps beyond what structured fields supply.

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 obligation to clarify semantics, and it adds nothing—no mention of time/coordinate expectations, timezone handling, or the sidereal-vs-tropical zodiacType option. The four required inputs are self-evident, but the agent gets no help reconciling low-coverage fields such as city, name, cosmogram, and ayanamsaId.

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-less but unambiguous resource: the sidereal natal sign chart (Rashi), which is the D1 varga. It also frames it as the 'foundation of Vedic analysis,' which hints at its primacy, but it never contrasts with the many varga siblings (D2, D9, D10, etc.) whose names differ only by number, so an agent must infer the distinction from the name alone.

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 explicit when-to-use guidance and no alternative is named. 'Foundation of Vedic analysis' weakly implies it is the starting chart, but nothing tells the agent when to pick D1 over astroway_vedic_varga_d9 or astroway_specialized_vedic_divisional, nor are any prerequisites stated.

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