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

No annotations are provided, so the description carries the full behavioral burden. It only says current temperature is provided via Open-Meteo; it does not disclose whether the tool makes an external network call, what units are returned, how errors are handled, or that most inputs 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 very short and front-loaded, with no filler words. However, it is slightly under-specified for a tool with nine parameters, so it does not fully earn a 5.

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 output schema, no annotations, and an input schema with many seemingly irrelevant parameters, the description is incomplete. It does not tell an agent which parameter to supply, what the response looks like, or what to expect from the large set of optional fields.

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 description adds minimal parameter context by mentioning 'city', but it does not clarify which of the nine schema properties are relevant, whether city is required, or what format is expected.

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 provides current temperature for a city and names the data source (Open-Meteo). It is specific enough to distinguish weather-hint from siblings like geo-hint or timezone, though it lacks an explicit verb like 'returns' or 'gets'.

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 guidance on when to use this tool versus alternatives, no mention of required inputs, and no exclusions. The description simply states the function without explaining that only 'city' matters or that the other eight schema parameters are effectively ignored.

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