Compute Synastry

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true. Description adds that the tool returns aspects from person A to B and positions, and that locations are not needed. No contradictions, but could disclose more about aspect calculation details like orbs.

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?

Well-structured: opens with a clear purpose, then key details, conditions, and ends with a concrete example. Every sentence is informative and necessary.

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?

Given rich schema, annotations, and output schema, the description covers what the tool does, parameters, return values (aspects + positions), exclusions (locations), and provides an example. It is complete for a 5-parameter tool.

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% with descriptions for each parameter. Description adds value by explaining datetime and timezone usage, providing an example, and describing the zodiac enum with three options. It goes beyond the schema.

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 clearly states it computes cross-chart aspects between two natal charts for relationship compatibility, specifying it returns aspects and positions. It distinguishes itself from sibling tools like compute_natal_chart (single chart) and compute_composite_chart (composite chart) by focusing on synastry.

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?

Explicitly states when to use: 'Locations are not needed' and when not to: for house overlays, compute natal charts separately. Provides clear context and alternatives.

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