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

There are no annotations, so the description carries the full behavioral burden. It reveals only that the tool fetches current temperature from Open-Meteo; it does not disclose that the other eight schema parameters appear to be ignored/discarded, nor any error handling, units, or side-effect behavior.

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 front-loaded sentence with no filler, and the key information (current temperature, city, Open-Meteo) appears immediately. It is concise, though arguably too sparse for the tool's complexity.

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 and no output schema, the description should explain return format, units, required parameters, and behavior with ignored inputs. It does none of this, and the nine-parameter schema with all-optional fields makes the call contract unclear.

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 is 3. The tool description adds the pointer that city is the meaningful input, but it doesn't explain the role of the remaining parameters or that they are discarded, leaving the large optional schema 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 'Current temperature for a city via Open-Meteo' states a specific resource and data source, clearly identifying the tool's function. It does not explicitly differentiate it from sibling hint tools like geo-hint, so it falls short of a 5.

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 provided about when to use this tool instead of siblings, whether city is required, or how it relates to other hint tools. The presence of nine unrelated optional parameters makes this omission worse; an agent has no way to know which parameter to populate.

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