divine_get_matching_planetary_positions

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

Annotations already convey read-only, idempotent, non-destructive behavior, so the description does not need to repeat safety traits. It adds useful output-shape context ('side-by-side planetary positions for P1 and P2') and domain framing. It does not disclose response size, pagination, or other potential quirks, but with annotations and an output schema present, this is acceptable.

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 two short sentences with no filler. The first sentence front-loads the core action and resource, and the second sentence adds value by clarifying the output format and use case. Every sentence earns its place.

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 the rich annotations, an output schema, and a detailed property schema, the description is mostly complete for an agent to select and invoke the tool. It clearly identifies the pair-based nature and intended purpose. The main gap is not explaining how this relates to the very similar single-person divine_get_planetary_positions tool, but overall the context is sufficient.

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 0% at the top level, so the description must compensate for parameter guidance, but it does not. It only restates that there are two persons, while the actual input is a complex object requiring 22 fields. The nested schema properties have examples, but the tool description itself adds almost no parameter-level meaning.

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 states a specific verb and resource: 'Get planetary positions for both persons in matchmaking.' It clearly distinguishes itself from single-person planetary position tools by emphasizing 'side-by-side' positions for P1 and P2, and it names the domain purpose (compatibility analysis). This is not a tautology and clearly identifies what the tool does.

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 an implied usage context: 'useful for detailed compatibility analysis beyond standard matching scores.' This helps an agent choose it over standard matching-score tools. However, it does not explicitly name alternatives like divine_get_planetary_positions or state when not to use this tool, leaving some routing inference to the agent.

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