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

There are no annotations, so the description must carry the behavioral burden. It discloses an external dependency on Open-Meteo but says nothing about expected inputs, error conditions, side effects, or what happens with the unrelated schema parameters. The schema descriptions hint that values are discarded, but the description itself does not.

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 a single concise sentence with no filler. It front-loads the core function and the data source, though it omits a verb and any usage context.

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 tool with no output schema and no annotations, this description is under-specified. An agent cannot determine the required parameter among nine optional ones, what response format to expect, or what makes this different from other hint tools. The mismatch between the weather description and the generic schema further reduces completeness.

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 100%, so the baseline applies. The description adds no parameter details beyond mentioning city, which is already described in the schema. It doesn't clarify why the other eight parameters exist or how they relate to the weather function.

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 the tool's purpose as returning current temperature for a city via Open-Meteo. This is a specific, identifiable function that distinguishes it from siblings like geo-hint, though it is phrased as a noun phrase rather than an explicit verb.

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?

No guidance is given about when to prefer this tool over alternatives such as geo-hint, web-fetch, or fetch-status. The schema lists nine optional parameters, but the description does not indicate which should be provided for a weather lookup.

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