Western Synastry

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

The annotations cover read-only, idempotent, and non-destructive behavior. The description adds meaningful behavioral details beyond annotations, including that standard inter-chart orbs are used, house_system is ignored for synastry, and response_format controls output. It does not mention rate limits or error cases, but those are not required given the annotations.

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 concise and well-structured, using short labeled sections for workflow, input contract, and disambiguation. The DO NOT CONFUSE section is especially efficient at preventing misuse. The full output contract link is a reasonable addition rather than unnecessary verbosity.

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?

The description provides sufficient context for agent selection and invocation, including output format, ignored parameters, and relationship to sibling tools. Since the context indicates an output schema exists and a full output/error contract link is provided, the description does not need to enumerate all return fields or error codes.

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?

The input schema already provides complete descriptions for all parameters. The description adds important semantic details such as 'house_system ignored for synastry payload' and explains that person1 and person2 are WesternBirthData objects, which helps agents understand which nested fields are relevant.

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 an aspect grid between two natal charts using the tropical zodiac and returns inter-chart aspects. The 'DO NOT CONFUSE WITH' section explicitly distinguishes it from composite charts and numeric compatibility scores, so an agent can select the correct tool.

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 gives useful context for when to use the tool, such as 'Useful for relationship compatibility analysis', and provides a WORKFLOW section telling agents to fetch individual natal charts first and use composite charts afterward. It also clarifies that it returns raw aspects unlike the numeric compatibility tool, though it does not explicitly state 'use this instead of X when Y'.

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