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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description usefully adds the response shape (12 houses with planets + state) and the 20-credit cost tier, which are real behavioral facts. It does not disclose anything about required inputs or server-side defaults beyond that.

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 front-loaded sentences plus short metadata tags; nothing is wasted. It could be marginally tighter, but it reads cleanly and leads with the purpose rather than burying it.

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 and annotations exist, so return-value and safety explanation burdens are lifted. Even so, for a 15-parameter chart tool the description omits the four required inputs and key defaults (Lahiri ayanamsa, house system), leaving an agent to infer call shape entirely from the schema.

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?

With only 33% schema description coverage across 15 parameters, the description is expected to compensate and it does not: it never mentions date, time, latitude, longitude, ayanamsa, houseSystem, or the compact-mode fields/precision options. The one-third of parameters that are documented live entirely in the schema, so the description adds no parameter meaning.

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 concrete verb+resource: the Lal Kitab kundali grid with 12 houses, each listing planets and their state. It also names the sibling it is a companion to (/teva for visualization), which helps distinguish it from the many other lal_kitab_* tools. Not fully differentiated from the broader Lal Kitab sibling set (debts, remedies, planet_house_effect), but the core purpose 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?

"Companion to /teva for chart visualization" implies a pairing, giving some context for when to reach for this over the teva output. However, there is no explicit when-to-use/when-not guidance and no mention of prerequisites (birth data precision, ayanamsa choice) needed to call it correctly.

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