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

With no annotations, the description carries the full burden for disclosing behavior, but it does not mention that this performs an external network call to Open-Meteo, whether it is read-only, or how failures and units are handled. Some parameter descriptions hint at non-actions like 'discarded' and 'no disk access', but tool-level behavior remains opaque.

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 highly concise with no filler, but it omits critical operational details. It is one short sentence, so it earns credit for brevity, but not for being appropriately complete.

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?

With 9 optional parameters, no required input, no output schema, and no mention of units, return format, or error handling, the description is far too incomplete for an agent to invoke correctly. The presence of many unrelated parameters further compounds the ambiguity.

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?

Although every parameter has a description, most are unrelated to the weather purpose (e.g., feed, json, path, query) and do not clarify which parameters are actually relevant. The city parameter lacks format guidance, and the schema's optionality leaves ambiguous what input is truly needed.

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 core function: returning the current temperature for a city via Open-Meteo. It names both the resource (temperature) and the external provider, which is enough to distinguish it from sibling tools like web-fetch or timezone.

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 given about when to use this tool versus alternatives, nor are there prerequisites, exclusions, or conditions. The description is only a bare functional statement with no usage direction.

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