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

There are no annotations, so the description carries the burden of behavioral disclosure. It usefully reveals an external API dependency via Open-Meteo and the time-sensitive nature of 'current' temperature, but it does not explicitly state that the call is read-only, side-effect-free, or how failures or rate limits behave.

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 that front-loads the core behavior and data source. It contains no wasted words and is appropriately minimal for a simple lookup 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?

The essential action and source are present, but there is no output schema and no annotations, and the description does not state return format, units, or how the eight non-city parameters relate to the tool's purpose. The schema descriptions mitigate some ambiguity, but the definition is not fully self-sufficient for a 9-parameter tool.

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%, and each parameter already has a description including note about values being discarded, so the baseline is 3. The tool description itself adds no parameter-level meaning beyond identifying 'city' as the relevant input, and the presence of eight other unrelated parameters still creates ambiguity about which arguments matter.

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 identifies the tool as returning current temperature for a city and names Open-Meteo as the source. This is specific enough to distinguish it from the generic validation siblings, though it does not explicitly contrast with related tools like geo-hint. The many unrelated optional schema parameters slightly undercut the clarity.

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 description provides a clear usage context: use this tool when a current city temperature is needed. It does not mention alternatives, exclusions, or that only the city parameter should be supplied while the other parameters appear to be ignored, so it stops short of full routing guidance.

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