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

With no annotations, the description carries full responsibility for disclosing behavior. It mentions Open-Meteo as a source, implying a network call, but it does not state read-only status, error handling, caching, or what happens when the city is invalid or missing.

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 wasted words. It immediately communicates the core function without padding.

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 tool has nine optional parameters, no output schema, and no usage context, while the parameter descriptions undermine the stated purpose. An agent would not know which parameters to pass, what response to expect, or how to handle failures.

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 descriptions are largely irrelevant or contradictory. The city parameter is described as 'discarded after the call,' which directly conflicts with the stated purpose, and the other eight parameters have no clear relationship to weather lookup.

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 states a specific action and resource: 'Current temperature for a city via Open-Meteo.' It is clear enough about the tool's core purpose, though the name 'hint' introduces slight ambiguity about whether it returns exact or approximate data.

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 such as geo-hint or timezone. The description does not mention prerequisites, fallback behavior, or situations where the tool should not be used.

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