fnd

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

No annotations are provided, so the description carries full burden. It implies a read-only GET request via the example URL but does not disclose rate limits, authentication, idempotency, or potential side effects.

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 includes a comprehensive list of response keys, which is helpful given the lack of an output schema, but it makes the description longer than necessary. It could be more concise by moving response details elsewhere.

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 a single optional parameter and no output schema, the description adequately covers input and output format. However, it lacks details on error handling, rate limits, or how to handle the response, and does not help with tool selection among siblings.

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 adds value by listing allowed values for the 'lang' parameter (en, tc, sc) and providing a request example, which goes beyond the schema's brief description. Schema coverage is 100%, so baseline is 3; the extra detail justifies a 4.

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 '9-day Weather Forecast (fnd) API Request', specifying the verb (fetch) and resource (9-day forecast). However, it does not differentiate from sibling weather tools like 'clmmaxt' or 'flw', which may also provide forecasts.

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 request example and parameter info but lacks explicit guidance on when to use this tool versus alternatives. No when-not-to-use or context relative to sibling tools is given.

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