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

With no annotations, the description carries the full burden, but it only states the data source and does not disclose whether the tool makes a network request, is read-only, or handles missing cities. No side effects or limitations are mentioned.

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 front-loads the core purpose. However, the structure provides no additional details or parameter context, making it too sparse for a tool with nine inputs.

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 incomplete for effective use: it does not specify required parameters, return format, error behavior, or what happens with the extraneous schema fields. The absence of an output schema further reduces the context available to an agent.

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 the schema has 100% description coverage, the descriptions are mismatched and confusing (e.g., 'discarded after the call') and do not clarify which of the nine string parameters is actually used for the city. The 'city' parameter description is self-contradictory, saying it is discarded after the call.

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 via Open-Meteo, identifying the resource and external provider. It is distinguishable from sibling tools by its weather-specific purpose, though it does not specify which input parameter is used.

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 provided about when to use this tool instead of alternatives such as geo-hint or timezone. The description does not mention conditions, prerequisites, or fallback scenarios.

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