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 mentions the return value ('city ID') and its purpose for other tools, but lacks details on error handling, rate limits, authentication needs, or what specific city information is returned beyond the ID. This is a significant gap for a tool with no annotation coverage.

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 with two sentences that efficiently convey the tool's purpose and output utility. It's front-loaded with the main action and avoids unnecessary details, though it could be slightly more structured by explicitly separating lookup methods from the return value explanation.

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, no output schema, no annotations), the description is adequate but incomplete. It covers the basic purpose and output usage, but lacks details on behavioral aspects like error cases or response format. Without annotations or an output schema, more context on what 'city information' entails would improve completeness.

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?

Schema description coverage is 100%, so the schema already documents both parameters thoroughly. The description adds minimal value by mentioning lookup methods ('name, ID, or coordinates') and the return purpose, but doesn't provide additional syntax or format details beyond what the schema specifies. This meets the baseline for high schema coverage.

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: 'Look up city information by name, ID, or coordinates.' This specifies the verb ('look up') and resource ('city information') with multiple lookup methods. However, it doesn't explicitly differentiate from sibling weather tools, which are for retrieving weather data rather than city information.

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 implies usage by stating 'Returns city ID that can be used with other weather tools,' suggesting this tool should be used as a prerequisite for weather-related operations. However, it doesn't provide explicit guidance on when to use this tool versus alternatives or any exclusion criteria, leaving some ambiguity about its specific context.

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