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

With no annotations, the description carries the full burden. It discloses the computation and the return shape, and 'Calculate' reasonably implies a pure, side-effect-free operation, but it says nothing about determinism, prerequisites (what date/place basis is needed), latency, or error behavior.

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 labeled WHEN TO USE / WHAT IT DOES / RETURNS structure is front-loaded and scannable, and no sentence is pure filler. The WHEN TO USE claim is somewhat redundant with WHAT IT DOES, keeping it just short of a 5.

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 describing return values is optional rather than required. The definition is still incomplete on the input side: for a calculation that needs an 8-parameter date/time/place tuple, nothing tells the agent which datetime and location to 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?

Schema description coverage is 0% across 8 parameters, so the description must compensate and does not. It never explains that year/month/day/hour form the birth or reference datetime, nor that latitude/longitude/timezone_offset default to India (20.59, 78.96, 5.5) — a default an agent could easily apply unintentionally.

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 ('Calculate Ashtakavarga (eight-fold strength) tables') and spells out the two table types produced (bhinna- and sarva-ashtakavarga bindus). It does not, however, differentiate this from sibling calculations like calculate_transits or calculate_birth_chart, which an agent must distinguish between.

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 WHEN TO USE section states a context ('for transit analysis and planetary strength'), but it largely restates the tool's own output ('needs the bhinna-ashtakavarga and sarva-ashtakavarga bindus'). There are no exclusions or named alternatives, so the agent is left to infer when this beats calculate_transits or calculate_birth_chart.

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