MCP Weather 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. While it mentions the tool 'gets' data (implying a read operation), it doesn't address important behavioral aspects like error handling, rate limits, authentication requirements, data freshness, or whether it's a real-time or cached service. The description is minimal and lacks behavioral context.

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 perfectly structured and concise. It begins with a clear purpose statement, then has well-organized sections for Args and Returns with bullet-point style explanations. Every sentence adds value, and there's no redundant or unnecessary information.

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 that there's an output schema (which handles return values), the description provides good context for a simple read operation. It covers the purpose and parameters well. However, for a tool with no annotations, it could benefit from more behavioral information (like error cases or performance characteristics) to be fully complete.

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 description provides excellent parameter semantics beyond the input schema. The schema has 0% description coverage and only shows parameter names and types. The description adds meaningful context: 'city: City name, e.g. "Berlin"' and 'country: Optional country filter, e.g. "DE" or "Germany".' This includes examples, clarifies that country is optional, and explains what the parameters represent.

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 conditions for a city.' It specifies the verb ('Get') and resource ('current weather conditions for a city'), but doesn't explicitly differentiate it from its sibling 'get_daily_forecast' beyond the 'current' vs 'daily' distinction. This makes it clear but not fully sibling-differentiated.

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 sibling 'get_daily_forecast' or any other alternatives. It simply states what the tool does without context about when it's appropriate or when other tools might be better suited.

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