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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the external Open-Meteo source, but does not explain that the tool is read-only, that only the city parameter is used while others are discarded, what the return format is, or how failures such as unknown cities are handled.

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 wasted words. It immediately communicates the core purpose and data source, which is appropriate for a simple tool.

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?

Despite the simple purpose, the tool has nine optional parameters, no output schema, and no annotations. The description does not explain what the response looks like, which parameters are meaningful, or the fact that most parameters appear to be accepted only to be discarded. An agent could easily be confused about how to invoke it correctly.

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 a small amount of meaning by indicating that the city parameter is the relevant one, but it does not clarify why nine unrelated optional parameters exist or how they interact with the weather lookup.

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's function: returning the current temperature for a city, with the data source identified as Open-Meteo. This is specific enough to distinguish it from siblings like geo-hint or timezone, though it does not explicitly name alternatives or contrast itself with other hint tools.

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 about when to use this tool versus the many siblings, nor any exclusions or alternative routing. The description only says what the tool does, leaving the agent to infer that it is for weather lookups.

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