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

With no annotations provided, the description carries the full behavioral disclosure burden, but it only states the happy path. It does not disclose that non-city parameters appear to be discarded, that an external Open-Meteo call is made, what units are returned, or what happens when no city is provided; there is also no output schema to fill these gaps.

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 sentence with no filler and is front-loaded with the primary purpose. However, for a tool with nine unrelated optional parameters and no output schema, it is under-specified rather than appropriately sized.

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 description is not enough to invoke the tool reliably: it does not state which parameter should be supplied, what the response looks like, or how to treat the many irrelevant schema parameters. With no annotations, no output schema, and a large sibling list, the available context is insufficient.

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 even without parameter details in the tool description. The description reinforces that 'city' is the meaningful parameter, but it does not clarify that the other eight optional parameters are irrelevant or ignored, which is a meaningful gap for such an overloaded schema.

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 names the action (current temperature), the resource (a city), and the data source (Open-Meteo), making the core function clear. It is not phrased as an imperative verb and does not explicitly differentiate from sibling 'hint' tools, but it is specific enough to identify a weather lookup.

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 use case is implied: an agent can infer to call this tool when a current temperature for a city is needed. However, there is no explicit when-to-use or when-not-to-use guidance, and the sibling list includes related tools like geo-hint that could be confused with it.

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