space.close-approaches

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

No annotations are provided, so the description carries the full burden. It discloses the data source (NASA JPL CAD), sorting order (nearest-first), and output fields. However, it does not mention rate limits, authentication requirements, or that this is a read-only query. The description is adequate but not exhaustive for a tool with zero annotation coverage.

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 a single, well-structured sentence that front-loads the purpose and includes key details (data source, output fields, sorting). Every word adds value with no redundancy. It is concise and easy to scan.

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 explains what the tool returns (output fields) and the high-level input criteria, but given no output schema, it could be more explicit about input parameter formats and constraints. The tool is relatively simple with 4 self-explanatory parameters, so the description is moderately complete but could include details like date format examples or note that distMaxAu defaults to 0.05.

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 has 0% description coverage (no parameter descriptions), and the tool description only vaguely references 'date window + max distance' without explaining each parameter's meaning, format, or constraints (e.g., dateMin/dateMax are date strings, distMaxAu is in AU). The description does not compensate for the lack of schema descriptions, leaving agents to infer parameter semantics from names alone.

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 exactly what the tool does: returns near-Earth close approaches with specific output fields (designation, date, distance, velocity, magnitude) and sorting order. It specifies the data source (NASA JPL CAD) and the filtering criteria (date window + max distance), which distinguishes it from sibling tools like space.body or space.skywatch.

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 implies usage (when you need close approach data within a date range and distance limit) but does not explicitly state when to use it versus alternatives or provide 'when-not-to-use' guidance. No mention of prerequisites or edge cases, leaving the agent to infer usage context from the description alone.

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