Weather API MCP Server

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 behavioral disclosure. It states the tool returns weather data but lacks details on permissions, rate limits, error handling, or data freshness. For a read operation with no annotations, this leaves significant gaps in understanding how the tool behaves beyond basic functionality.

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 concise and front-loaded, stating the core purpose in the first sentence and adding return details in the second. Both sentences earn their place by clarifying functionality and output. It avoids redundancy and is appropriately sized for a simple tool.

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?

Given the tool's moderate complexity (2 parameters, nested objects, no output schema), the description is minimally adequate. It covers the basic purpose and return data but lacks details on behavioral traits, usage context, and output structure. Without annotations or an output schema, it leaves the agent to infer operational aspects, making it incomplete for optimal tool selection.

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, thoroughly documenting the 'location' and 'options' parameters. The description adds no additional parameter semantics beyond what the schema provides, such as examples or constraints. With high schema coverage, the baseline score of 3 is appropriate, as the description does not compensate but also does not detract.

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: 'Get current weather information for a location.' It specifies the verb ('Get') and resource ('weather information'), and mentions the return data (temperature, humidity, conditions). However, it does not explicitly differentiate from sibling tools like getHourlyWeather or getWeatherForecast, which likely provide different temporal scopes.

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 this tool versus its siblings (getHourlyWeather, getWeatherForecast, lookupCity). It mentions returning 'current weather,' which implies a distinction from forecast or historical data, but does not explicitly state alternatives or exclusions. Usage context is implied rather than clearly defined.

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