Current weather (MeteoSwiss)

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds that it returns measured data only (no forecasts) and clarifies the source (MeteoSwiss station) and the selection criterion (nearest to a Swiss municipality). This adds context beyond annotations without contradicting them.

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?

A single, information-dense sentence that front-loads the core purpose and immediately clarifies the scope and limitation. No wasted words, and the structure is easy to parse.

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 an output schema, so return format is covered. The description explains what data it returns, where it comes from, and what it doesn't do. With annotations handling safety and the schema handling parameters, nothing essential is missing for an agent to use it correctly.

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 input schema has 100% description coverage for both parameters, including examples for 'place' and an enum with default for 'language'. The description adds no additional parameter-specific meaning, which is acceptable since the schema already fully documents them. Baseline 3 is appropriate.

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 the latest measured weather (temperature, humidity, precipitation, wind) at the MeteoSwiss station nearest to a Swiss municipality. It also explicitly notes 'Measurements only, no forecasts,' which sharply distinguishes it from any forecast tool. No sibling covers weather, so this is unambiguous.

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 a clear context: for current measured weather at a Swiss location. It explicitly excludes forecasts ('Measurements only, no forecasts'), which tells the agent when not to use this tool. While it doesn't name an alternative, none exists among siblings, so the guidance is sufficient.

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