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

With no annotations, the description carries the full burden and does well: it discloses the input factors (wind gusts, convective potential, winter/sustained precipitation, heavy cloud cover), the temporal granularity and horizon, and the access mechanics (GET endpoint, $0.02 via x402). It omits rate limits, caching/freshness, and error behavior, keeping it below a 5.

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 purpose is front-loaded and each sentence adds information, but the 48-hour horizon is stated twice ('for the next 48 hours' then 'over the next 48 hours'), which is mild redundancy. The trailing HTTP/price/docs bracket is dense but earns its place for a paid endpoint.

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?

For a parameter-less read endpoint with no output schema, the description adequately covers what is returned (6-hour risk scores and their drivers) and how to access it. The return shape is described only by reference ('same shape as the generic delay-risk endpoint'), which assumes prior knowledge of that sibling rather than spelling out the payload.

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 tool takes zero parameters (additionalProperties: false), so per the rubric the baseline is 4. There are no parameters whose semantics need explaining beyond what the schema provides.

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?

States a specific resource (weather-driven delay risk for Seattle-Tacoma / SEA), a precise horizon (next 48 hours), and the resolution of the output (6-hour risk scores). It also names the sibling it is bound from ('generic delay-risk endpoint') and what inputs feed the score, so an agent can differentiate it from weather_aviation-delay-risk without opening a schema.

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?

It explicitly names the alternative (the generic delay-risk endpoint) and the condition that selects this one ('bound to SEA'), which routes the agent correctly. It stops short of stating when-not to use it (e.g. non-SEA airports or horizons beyond 48h), so it falls just short of a full 5.

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