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

With no annotations and no output schema, the description carries the full disclosure burden and does real work: it states the forecast horizon, the period-based structure, the specific hazard flags (low clouds, storms, snow, strong gusts) and that a delay-risk rating is included. It omits update cadence, data source, units, and any coverage limitations, so it is strong but not exhaustive.

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?

It is a single dense sentence that front-loads the scope (24-30 hours worldwide) before enumerating return contents, and the closing exclusion is well placed. It reads as slightly run-on, but each clause contributes information rather than padding.

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 one-parameter read tool with no annotations and no output schema, the description conveys enough about the return shape (periods, weather fields, delay-risk rating) for an agent to know what it will get and when it is appropriate. Missing interpretation details such as units or the delay-risk scale are minor given the overall coverage.

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 coverage is 100% and the single airport parameter is already documented as accepting IATA or ICAO codes. The description only reinforces this with "any airport worldwide," adding no syntax, format, or validation detail beyond the schema, so the baseline 3 applies.

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 names a specific verb and resource (airport weather forecast) and scopes it precisely to the next 24-30 hours worldwide, listing the granular fields returned (wind, gusts, visibility, ceiling, flight category, delay-risk). It implicitly separates itself from travel_airport_status (current conditions) by emphasizing the forecast horizon, but never names a sibling explicitly, keeping it short of a 5.

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 provides a clear exclusion, "Not for flight planning," which steers the agent away from a plausible misuse. However, it names no alternative tool (e.g., travel_airport_status for current conditions), so the when-to-use guidance is contextual rather than fully routed.

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