Midpoint Trees (Uranian)

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely new behavioral context: the endpoint and the cost ('20 credits, Tier 2'), which matters for budgeting calls. It does not describe result shape or limits, though an output schema exists to carry 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?

One front-loaded sentence carries the whole functional statement, and the bracketed Group/Endpoint/Cost lines are compact structured metadata rather than prose padding. Nothing is repeated or wasted.

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?

For a complex Uranian technique with a deeply nested input and an existing output schema, the description covers intent and cost adequately. It leaves open which focal planets are evaluated and how the trees relate to the sibling midpoint tools, which an agent cannot infer from the schema 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%, and the nested body schema documents birth data, house system, timezone handling and orb in far more detail than the description does. The only param-level signal is 'within a given orb,' which the schema already specifies with bounds. Baseline 3 is right.

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 verb (Calculate) and a specific resource (Uranian midpoint trees and planetary pictures/symmetries), plus the scope 'for each focal planet within a given orb.' That is far more than a restated name. It stops short of distinguishing itself from close siblings such as astroway_aspects_midpoints or astroway_cosmobiology_midpoint_pictures, which an agent must resolve on its own.

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 or when-not-to-use guidance. Given the crowded sibling set (midpoints, midpoint_pictures, personal_point_tree, transit_midpoints), an agent has no stated basis for choosing this tool over those. The phrase 'within a given orb' hints at configuration but not at selection.

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