Dashas: Vimshottari Pratyantardasha

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

The annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds genuinely non-redundant context: the 20-credit Tier 2 cost and the three-level cascade the server performs (MD → AD → 9 PDs), which tells the agent the computation is derived rather than parameterized.

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 tight sentences lead with the concept and definition, followed by compact metadata lines for group, endpoint and cost. No sentence is padding.

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 a full output schema and complete annotations, the description needn't explain return values, and it does add cost and cascade behavior. The minor gap is that the targetDate/targetTime fields in the schema are undocumented anywhere, and the description doesn't hint at how they select the period.

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?

There is a single body parameter with 100% schema description coverage and a very rich nested schema covering birth data and targetDate/targetTime, so the schema does the heavy lifting. The description adds nothing about what those fields mean or that target date/time control which PD window is returned, so baseline 3 applies.

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?

It names the specific resource (Pratyantardasha) and states its level in the dasha hierarchy ('sub-sub-period within the running Antardasha') plus the concrete output ('return 9 PDs of that AD'). That level language separates it from the maha/antar/prana/sookshma siblings, though the description 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 by the level explanation — an agent can infer this is for finer timing work inside an antardasha — but there is no statement of when to choose pratyantar over prana or antar, and no prerequisites (e.g., that natal birth data must be supplied) are stated outside the schema.

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