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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds the billing context (20 credits, Tier 2), which is genuinely useful for cost-aware planning, but says nothing about what the output contains or how the dosha is derived.

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 short bracketed lines with no filler; the subject is front-loaded. The Group/Cost tags are metadata rather than prose, so the payload is minimal but efficient.

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 needn't be explained, but for a 15-parameter tool with weak schema coverage the description should at least say which birth inputs are mandatory and how this differs from the Parashara/KP Kalsarpa siblings. It leaves those gaps open.

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?

Fifteen parameters with only 33% schema description coverage, and the description contributes zero parameter detail. Required birth data (date, time, latitude, longitude) and the meaningful ayanamsa/houseSystem/timezone choices are left entirely to the schema, which only partially documents them.

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?

Names a specific dosha (Kalsarpa, i.e. Rahu-Ketu encirclement) and its interpretive tradition (Lal Kitab remedies), which distinguishes it from the sibling Parashara kaal_sarp and KP kalasarpa variants. There is no explicit verb (compute/report), but the resource and school are unambiguous.

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?

No when-to-use guidance, no prerequisites, and no mention of the adjacent school-specific Kalsarpa siblings (Parashara, KP) that an agent could confuse it with. The reader must infer selection criteria entirely.

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