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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds one genuine behavioral fact — the sub-periods are an 'equal split' of the running mahadasha (distinctive to Sthira dasha versus proportional systems) — plus the credit cost (20 credits, Tier 2). It says nothing about edge cases such as what happens when targetDate falls outside the running MD, or output shape. Useful but thin beyond the annotations.

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?

One front-loaded sentence, with group/endpoint/cost metadata clearly separated. Nothing is padded. The [Endpoint: POST ...] line adds little for an agent choosing a tool, keeping this 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 return values need no explanation, and annotations cover the read-only safety profile. What is missing is domain context: 'MD' is undefined and the five-level dasha nesting (Maha > Antar > Pratyantar > Sookshma > Prana) that distinguishes this tool from its identical-looking siblings is never stated. Adequate for an expert, thin for a general agent navigating this large tool family.

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 nested body (date, time, latitude, longitude, timezone, ayanamsa, houseSystem, etc.) and the compact-mode fields/precision parameters are all documented in the schema itself. The description only pins down targetDate by name and does not explain targetTime/targetTzOffset or how the target date interacts with the birth data. Baseline 3 applies since the schema does the heavy lifting.

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 and scope ('Sthira Antardasha: equal-split sub-periods of running MD at targetDate'), which tells the agent this returns the Antar (second) level of the Sthira dasha tree rather than the Maha or Pratyantar levels. The abbreviation 'MD' is left undefined and no sibling is named explicitly, so the differentiation from sthira_maha/sthira_pratyantar relies on the agent parsing the name. Clear but not self-explanatory.

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 statement, no exclusion of alternatives, and no prerequisites. With roughly thirty near-identical dashas siblings in the same namespace (Vimshottari, Yogini, Chara, Shoola, etc., each with maha/antar/pratyantar/sookshma/prana levels), the agent gets no guidance on how to choose this one over the others. The single sentence states content, not usage.

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