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

The description discloses that Open-Meteo is used, implying an external network call, but it does not mention side effects, error behavior, or how the tool handles the many unrelated optional parameters. No annotations are provided to fill this gap.

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 with no unnecessary words. It could be more informative, but it is efficiently structured.

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 no output schema, no required parameters, and a large set of seemingly irrelevant optional inputs, the description is far too incomplete for an agent to use correctly. It omits units, return format, and any explanation of the tool's actual behavior with respect to all schema 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?

The schema contains nine optional parameters, most of which have descriptions unrelated to weather (e.g., 'ref', 'feed', 'json', 'path', 'zone', 'query'), and the description does not clarify that 'city' is the meaningful input. An agent cannot reliably determine which parameters to supply or whether the others are ignored.

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 returns current temperature for a city and identifies Open-Meteo as the source. It is specific enough for an agent to understand the basic purpose, though it does not mention units or the exact return value.

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 gives no explicit guidance on when to use this tool versus alternatives, and there is no mention of expected inputs or conditions. The only implicit guidance is that it applies to weather lookups for a city.

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