faa_metar

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

The description supplements the readOnlyHint annotation by specifying what data is returned (temperature, dewpoint, wind, visibility, ceiling, flight category), the station ID format (ICAO codes), and the ability to query multiple stations comma-separated. This adds meaningful context beyond the annotation without contradicting it.

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 three short sentences, each providing necessary information: the primary action, returned fields, and input format rules. No redundant wording exists.

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 simple read-only nature, no output schema, and full schema parameter coverage, the description adequately covers the tool's core behavior and return values. It could mention the optional 'hours' parameter's effect, but the schema covers that, and the description sufficiently describes the default behavior ('current conditions').

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 baseline is 3. The description repeats the schema's explanation for 'ids' (ICAO codes, comma-separated) but adds no new semantic meaning beyond the schema. It does not mention the 'hours' parameter, but the schema already documents it fully.

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 uses a specific action verb 'Get' combined with a specific resource 'METAR weather observations for airports', and clearly distinguishes from sibling weather tools like faa_taf or faa_sigmet by naming the METAR product and the returned fields (temperature, dewpoint, wind, etc.).

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 does not mention when to use this tool versus alternatives such as faa_taf or nws_observation_latest, nor does it provide exclusions or when-not scenarios. It only provides operational details (ICAO codes, comma-separated stations), which is usage how-to, not usage selection guidance.

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