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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds genuine methodological context beyond that: 'deterministic' and the whole-sign house mapping rule. It still says nothing about input precision requirements or how the transit is scoped, so it is modest rather than rich.

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?

A single front-loaded sentence with no filler; the scope qualifier ('explicit instant') and mapping rule are packed in efficiently. It is appropriately sized, though it is so terse that it leaves no room for the usage guidance the tool needs.

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 no explanation, but for a 9-parameter tool with 0% schema coverage and a confusingly similar sibling, the description is too thin. It gives no parameter semantics, no invocation example, and no disambiguation from calculate_gochara_from_known_place.

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 9 parameters, so the description carries the full burden of explaining them. It gestures at the instant (date/time), place and natal Lagna but omits latitude/longitude/timezoneOffset ranges, the language enum, and the 0-11 sign indexing, leaving most parameters undocumented in both schema and description.

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+resource (calculates transit placements) with two qualifiers: an explicit instant and whole-sign houses from a supplied natal Lagna. An agent can tell this is a gochara/transit calculation. However, it never distinguishes itself from the near-identical sibling calculate_gochara_from_known_place, which is a real ambiguity.

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 when-to-use or when-not-to-use guidance, and no alternatives are named. The phrase 'explicit instant' and 'supplied natal Lagna' hints at the contrast with calculate_gochara_from_known_place, but the agent must infer that distinction itself rather than being told.

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