Sun & Moon Rise/Set Times

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is clear. The description adds detail about twilight types but does not mention data freshness, time zone handling, or edge cases (e.g., polar regions). With annotations covering core safety, a mid score is appropriate.

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?

Two sentences with no redundancy. The information is front-loaded: what the tool does, what it includes, and typical use cases. Every sentence adds value.

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?

For a simple read-only tool with a well-documented input schema and an output schema (assumed), the description provides sufficient context. It covers the main outputs and use cases. Lacks time zone info, but that is likely in the output schema.

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 100% coverage with clear descriptions for all three parameters. The description adds no parameter-specific details beyond 'any location and date'. Baseline 3 is correct as the schema does the heavy lifting.

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 retrieves sunrise/sunset, moonrise/moonset, transit times, and twilight types. It uses a specific verb ('Get') and resource. However, it does not explicitly distinguish from the sibling tool 'usno.astronomy.moon_phases', which could overlap in moon-related data.

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 lists concrete use cases (photography golden hour, agriculture, outdoor events), which helps the agent understand when to invoke this tool. It lacks explicit when-not-to-use or alternatives, but the use cases provide strong guidance.

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