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 mentions Open-Meteo as an external source, which is useful, but it does not disclose whether the tool makes a network call, whether it is read-only, or what side effects, if any, occur.

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 extremely concise: one sentence with no filler, redundant wording, or unnecessary detail. It is well-structured for quick parsing.

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?

There is no output schema and no explanation of the return format, units, or error behavior. With no required parameters and a schema containing many seemingly unrelated optional fields, the description does not provide enough context for a caller to confidently invoke the tool.

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?

Although every parameter has a description, most of the nine parameters are unrelated to 'current temperature for a city.' The schema includes ref, url, feed, json, path, zone, and query with plausible individual meanings, but the descriptions do not explain why they belong in a weather tool or how they relate to the stated purpose.

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 is a single specific statement: 'Current temperature for a city via Open-Meteo.' It identifies the action (return current temperature), the subject (a city), and the data source (Open-Meteo), so the tool's primary purpose is clear.

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?

There is no explicit guidance about when to use this tool versus the many sibling tools, nor any mention of when not to use it. The description implies it is for current city temperature, but it does not explain the intended selection criteria or exclude alternatives.

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