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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is fully covered. The description adds the substantive scope of the computation but says nothing about cost, determinism dependence on birth-time accuracy, or rate behavior beyond what annotations supply.

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: the front-loaded content inventory, then the usage trigger. Dense but every clause names a distinct computed quantity. No filler or restatement of the tool name.

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 described; annotations cover the safety profile. Given that, the description's enumeration of computed components plus the usage trigger is essentially complete for an agent to select and call it, with only parameter-level detail left to the schema.

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 75% and covers input format (date pattern, HH:MM, timezone IANA, offset fallback) plus the place/coordinate anyOf. The description adds no parameter guidance at all, so it neither compensates for the remaining gap nor expands on semantics. Baseline 3.

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 computed resource and enumerates its constituents (Shadbala with all six balas and required-strength ratio, Vimshopaka in four varga sets, Ishta/Kashta Phala, avasthas, friendships). This is far more specific than the title and clearly distinguishes it from the many analyze_* and calculate_* siblings.

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?

Explicitly states when to invoke it: 'Use when asked which planets are strong or weak, or to qualify a yoga.' That is a concrete trigger. It stops short of naming alternatives or exclusions (e.g. vs calculate_ashtakavarga or analyze_varga), so it is not a 5.

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