Star-planet parans (Brady)

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

Annotations already declare read-only, idempotent, non-destructive behavior, so the lower bar applies. The description adds genuine context beyond that: the computation is done on hour angles rather than polyline intersection, giving exact rather than quantised latitudes, and it reveals the row structure returned (which body does what, the latitude, the meridian). It stops short of stating explicitly that the chart coordinates are unused, which is the one non-obvious input behavior.

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?

Four sentences, front-loaded with the definitional claim and then the output shape and method. Dense but every sentence carries information; the parenthetical digression about minus-meridian pairs is slightly over-elaborate for a tool-selection description.

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 not be exhaustively described, and the description still sketches the row contents. What is missing for an agent to call this correctly is the sibling relationship to astroway_geo_parans and confirmation that the natal coordinates are ignored.

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 coverage is 100%, including detailed prose for timezone, houseSystem, ayanamsa, horizon, stars, planets and latitudeLimit, so the schema carries parameter meaning. The description adds nothing about any parameter, and the crucial point that latitude/longitude inputs do not affect the result appears only in the schema's own body description. 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?

The description gives a concrete definition of the resource: latitudes where a fixed star and a planet are simultaneously angular, with twelve event pairs per pair. That distinguishes it conceptually from a generic paran tool, but the sibling astroway_geo_parans is never named, so the agent must infer the split from the title alone.

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 statement of when to reach for this tool versus alternatives, no prerequisites, and no exclusions. In a catalog containing astroway_geo_parans, geo_local_space and the many ACG tools, the absence of routing guidance is a real gap even though the concept itself is explained.

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