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

Annotations already declare readOnly, idempotent, non-destructive, and non-open-world, so safety is covered. The description adds genuine context beyond that: the output is hard-coded to New Delhi IST, the date must be within a year either way, and providing birth_star conditionally adds that star's tārā for the day.

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?

Front-loaded with the core purpose, then the returned contents, then a compact two-clause parameter note. Dense but every clause adds information; the enumeration of limbs is long but earns its place by defining the payload.

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?

With an output schema present, return-value explanation is unnecessary, and the description covers scope, location, date bounds, and the conditional parameter. Minor omission: behavior on an invalid date or unrecognized birth_star name is not described.

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%, so the description carries the burden and does so well: date accepts the literal 'today' or YYYY-MM-DD bounded to one year either way, and birth_star is an optional nakshatra name. Only the exact accepted nakshatra spellings are left unspecified.

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 resource (the Hindu almanac/panchang) with its geographic and timezone scope (New Delhi, IST) and enumerates the exact contents returned (five limbs, sunrise/sunset, Rahu Kaal, chaughadia, tārā). This makes it clearly distinct in substance from festivals, monthly_forecast, and find_birth_star, though it never names those siblings explicitly.

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?

Usage is implied rather than stated: it tells the agent the tool is for 'a day' at New Delhi and that birth_star is optional, but gives no explicit when-to-use/when-not guidance and does not contrast itself with find_birth_star or monthly_forecast, which an agent might otherwise confuse it with.

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