Transits

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so safety is covered. The description adds genuinely useful non-schema context: the return content (applying vs separating aspects), the POST endpoint, and a concrete cost of 50 credits at Tier 3, which matters for budgeting. It says nothing about rate limits, error modes, or how large a result set can be.

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 compact sentences with the action front-loaded, followed by short bracketed metadata lines. Every element is short and skimmable, though the group/endpoint/cost lines are metadata rather than description prose.

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 explaining return values is not required, and the schema handles parameter semantics. However, the tool takes two distinct dates (natal birth data plus transitDate), and the description's single 'for a given date' phrasing obscures that two-date model, which is the main conceptual thing an agent needs before calling.

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 is extremely explicit about date/time formats, latitude/longitude, timezone handling and houseSystem letters, so the description is not required to carry parameter detail. It adds nothing beyond the schema — notably it never clarifies that the payload holds both natal birth data and a separate transitDate/transitTime.

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 and resource: 'Calculate transit planet aspects to natal planets for a given date', and adds that applying/separating aspects are returned. It is clear enough to distinguish from narrative or interpretive siblings, but it does not name any of the near neighbours (astroway_prognostics_transit_calendar, astroway_calendar_aspects, astroway_aspects_aspect_timeline) that an agent could easily confuse it with.

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?

Usage is only implied by the phrase 'for a given date' — nothing states when to choose this over the transit calendar or aspect timeline siblings, and no prerequisites or exclusions are given. An agent can infer the general context (calculating aspects between transiting and natal planets) but must open schemas to route correctly.

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