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

No annotations are present, so the description must disclose behavioral traits. It reveals an Open-Meteo dependency and the result is temperature, but it does not explain units, failure behavior, network/rate-limit characteristics, or that only the city input is used while other accepted schema parameters are discarded.

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, efficient sentence with no filler and leads with the key function. It is concise, though so sparse that it leaves important operational details to be covered elsewhere.

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?

With nine optional parameters, no required flags, no output schema, and no annotations, this one-sentence description is not enough for an agent to call the tool correctly. It fails to state that city is effectively required, what output format/units are returned, and what happens with the other accepted parameters.

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 coverage is 100%, so the baseline is 3. The description adds only that 'city' is the relevant input, which the schema already states; it does not clarify that the other eight optional parameters are irrelevant to this tool's weather 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 clearly states the tool returns the current temperature for a city using Open-Meteo, so an agent can grasp the core function. It does not explicitly contrast with sibling tools, though the weather/city focus is enough to distinguish it from geo-hint or lib-docs-hint.

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 phrase 'for a city' implies this tool is for city-weather lookups, but there is no when-to-use guidance, no mention of alternatives, and no conditions for when not to use it. The usage context is only implied, not stated.

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