Sun Times

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the tool is safe and idempotent. The description adds value by specifying what is computed (sunrise, sunset, twilight, day length), which provides behavioral context beyond annotations. No contradictions.

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 at two sentences plus an example and metadata. It is front-loaded with the core purpose, and the example aids understanding. The inclusion of group and cost information adds minor clutter but does not detract significantly.

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 fails to specify the output format or structure, which is important for a calculation tool without an output schema. While parameters are covered, the lack of return value documentation leaves the agent uncertain about what to expect.

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?

With 0% schema description coverage, the description is expected to clarify parameter meanings, but it only mentions 'date and geographic location' generically. It does not explain latitude, longitude, or timezoneOffset individually, and the example includes timezoneOffset without elaboration. This leaves parameter semantics ambiguous.

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 the tool calculates sunrise, sunset, twilight times, and day length for a given date and geographic location. This is a specific verb+resource combination that makes the tool's purpose immediately apparent and distinguishes it from the many astrological sibling tools.

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 indicates usage when date and geographic location are known, which is clear context. However, it does not explicitly state when not to use this tool or provide alternatives among siblings, but the astronomical nature of the tool contrasts with astrological siblings, making the usage fairly clear.

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