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

With no annotations, the description carries the full burden, and it does disclose the core behavior: a snapshot of current weather at a coordinate via Open-Meteo. However, it omits details like coordinate format, units, and the behavior when q is empty, though the output schema may mitigate some missing return-value details.

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 one short, front-loaded sentence that names the tool, the behavior, and the data source. It is appropriately sized for a simple tool, though it repeats the title 'Weather' at the start.

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 no annotations, one undocumented parameter, and no guidance on coordinate format or defaults, the description is not sufficient for an agent to confidently invoke the tool correctly. The output schema helps with return values, but critical input details are still missing.

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%, so the description must compensate, but it only says 'at a coordinate' without specifying the expected format of the q parameter (e.g., lat,long or decimal degrees). The parameter named q is otherwise completely opaque without the description.

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 resource (weather at a coordinate) and clarifies it is current conditions from Open-Meteo. It is clear and distinguishes the tool from weatheralerts, marineweather, and airquality by emphasizing 'current' and 'coordinate', though it does not explicitly name any sibling.

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 the tool is for coordinate-based current weather but gives no explicit guidance on when to choose it over alternatives like weatheralerts, marineweather, or airquality. There are no exclusion criteria or when-not-to-use statements.

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