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 disclosing behavior. It mentions Open-Meteo but does not describe network calls, side effects, error behavior, or what happens when the city is unknown. There is no contradiction, but behavior is largely undisclosed.

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 and clearly communicates the core function. It is well-structured and easy to parse, though the parameter schema is much larger than the description implies.

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?

There is no output schema, no required parameters, and no description of return format, units, or failure modes. An agent would not know what to pass or what to expect, making the tool incomplete for reliable invocation.

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, the schema contains nine optional parameters, many of which are irrelevant to weather (ref, url, feed, host, json, path, zone, query). The city parameter is described as 'discarded after the call,' which is confusing and undermines its role as the apparent input for the tool.

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 purpose: returning current temperature for a city using Open-Meteo. It is distinguishable from sibling tools like timezone, geo-hint, and web-fetch, even though it does not explicitly name those alternatives.

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 no guidance on when to use weather-hint versus other tools, nor any context about required inputs or expected call patterns. The single sentence is informative about what it does but not about how or when to invoke it.

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