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

The annotations already declare the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds genuinely new behavioral context: the default targetDate resolves to today UTC, and the call costs 20 credits at Tier 2 — a quota/cost disclosure the annotations do not carry.

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 identity of the result, then the default and formula, then the group/cost tags — no padding. The formula is arguably trivia for tool selection, but it is compact and does not bloat the definition.

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, and the params and annotations are well covered. The remaining gap is domain routing: for a complex dasha tool with dozens of near-identical siblings, the definition never states which level or which dasha system the agent should pick, leaving selection underdetermined.

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 100%, so the baseline is 3, but the description adds a semantic the schema omits: targetDate defaults to today UTC, which matters because the schema marks it optional with no stated default. The P.years × Q.years / 108 formula explains the domain computation but does not map to any input parameter.

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 resource (Ashtottari Antardasha) and defines it as '8 sub-periods of the running MD', which implicitly places it at the second level of the dasha hierarchy and separates it from the maha level. It does not, however, explicitly contrast itself with the adjacent antar/pratyantar/prana/sookshma siblings, so an agent must infer the level distinction from the word 'Antardasha'.

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, when-not-to-use, or alternative-naming guidance at all. With 50+ sibling dasha tools spanning 12 systems and 5 levels, the description gives the agent no routing rule for choosing this level over ashtottari_pratyantar or ashtottari_maha.

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