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

With no annotations provided, the description carries the full burden. It mentions 'retrograde re-hits' which is a useful behavioral detail, but does not explicitly confirm it is read-only or describe what happens on boundary conditions (e.g., aspect exact multiple times). The description implies a query operation, which is adequate.

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 sentences, extremely concise, and front-loaded with the core action. Every sentence provides essential information without redundancy.

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 tool's complexity (7 parameters, no output schema), the description covers the essential constraints and behaviors. It could be slightly improved by specifying the output format (e.g., returning ISO date strings), but it still provides sufficient context for an agent to invoke it correctly.

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 86%, and the description adds meaningful context beyond the schema: it explains the exclusive nature of target_lon and target_body, notes that body names are snake_case, and clarifies that the search includes retrograde re-hits. This adds value for correct parameter selection.

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 uses the specific verb 'find' and clearly identifies the resource: exact dates a transiting body makes an aspect within a range. It distinguishes from sibling tools like 'aspect_patterns' by focusing on exact dates rather than patterns.

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 provides clear input constraints such as providing exactly one of target_lon/target_body, converting dates to UTC, and a 50-year max range. However, it does not explicitly state when to use this tool over alternatives like 'transits' or 'aspect_patterns'.

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