ephemeris_transits

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

Annotations already mark it as read-only and idempotent. The description adds valuable behavioral context beyond that: credit cost (6 credits), tier-based search range limits (1/5/10 years), and the heavy-computation warning when omitting both planet lists. These are exactly the kinds of behavioral traits that help an agent.

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?

The description is well-organized with clear sections (EFFICIENCY TIP, ASPECT ANGLES, DEFAULT, SEARCH RANGE LIMITS, CREDIT COST). Every sentence earns its place; it is information-dense but never redundant. The first sentence immediately states purpose, front-loading key information.

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 tool with 9 parameters and no output schema, the description covers essential contexts: default behavior, compute cost, range limits, and examples. The only gap is a more explicit description of the return value structure, but the core usage requirements are fully addressed.

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%, but the description enriches parameters: it lists explicit default natal_points, explains aspect_angle semantics with examples, and gives parameter-combination patterns. This adds meaning beyond the schema's field descriptions, though the schema already covers the basics.

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 opens with a specific verb and resource: 'Search for astrological transit events affecting a natal chart over a date range. Returns exact transit moments — when transiting planets form specified aspects to natal planet positions.' This clearly distinguishes it from sibling tools like synastry or natal chart computations.

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?

Provides concrete usage guidance: an efficiency tip to always specify both transiting_planets and natal_points to avoid heavy computation, and examples for Saturn return, Uranus opposition, and outer-planet-to-Sun/Moon transits. It implies when to use the tool but does not explicitly name alternative tools or state when not to use it.

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