Parallel Aspects

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds two genuinely new facts: that both parallel and contra-parallel aspects are returned from a single call, and that the call costs 20 credits (Tier 2) — useful for cost-aware planning. It says nothing about the response shape or the default orb behavior, which keeps it at a middling score.

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?

A single front-loaded sentence defines the operation and its two aspect types, followed by short structured metadata lines for group, endpoint and cost. No sentence is wasted; the only small gap is that 'within orb' leaves the reader to find the value in the schema.

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?

With an output schema present, the description needn't explain return values, and the input schema is exhaustively documented. Safety is covered by annotations and cost is disclosed, so the definition is sufficient to invoke the tool correctly; only a default-orb note and a one-line alternative routing hint are missing.

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 birth-data object is documented in exceptional depth, so the schema carries the parameter burden. The description's 'all planets within orb' does add one useful semantic: there is no planet-selection input, everything is computed for every planet pair — but it does not state the effective default orb when the optional `orb` field is omitted.

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 precisely defined resource: parallel and contra-parallel declination aspects between all planets, with both terms explained inline. It is clearly distinct from the zodiacal-aspect siblings (aspect_bar, antiscia, aspect_timeline), though it never names an alternative to differentiate against explicitly.

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?

The description says what is computed but never when to choose this over the zodiacal aspect tools or which chart inputs are prerequisites. The only usable hints ('within orb', 'all planets') come from the description's phrasing rather than from any stated usage rule or exclusion.

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