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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds genuinely new behavioral context: the cost ('20 credits, Tier 2'), the endpoint, and the recursion rule ('equal-share subdivision; same direction at every depth'), which tells the agent how the periods are 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?

Front-loaded with the core semantics in the first clause, then structured metadata lines. No filler sentences; every element earns its place.

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 algorithm/cost metadata is present. The gap is decision support: for a tool surrounded by ~80 Vedic siblings at four different dasha depths, the absence of any routing guidance leaves the agent to infer selection from the name alone.

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 schema already documents birth data, fields and precision thoroughly. The description supplies no additional parameter meaning, so the 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?

States a specific computation: 'Chara Pratyantardasha: 3-level cascade (MD → AD → 12 PDs)', which pins down the dasha level and its subdivision structure. It distinguishes itself from the maha/antar/prana/sookshma variants only implicitly via the level name; there is no explicit routing statement, but the resource is 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, when-not-to-use, or sibling routing. Given siblings like chara_antar, chara_prana and chara_sookshma sit at adjacent levels, the description should say which level the agent wants, but it does not. Only the implicit '12 PDs' wording hints at scope.

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