wx_metar

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

With no annotations provided, the description carries the transparency burden. It states that both raw METAR and decoded fields (ceiling, visibility, wind, flight category) are returned, which is useful behavioral context. However, it does not disclose potential limitations such as data freshness, units, or behavior with invalid ICAO codes.

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 a single, well-structured sentence that front-loads the core action and result. Every phrase adds relevant information without waste.

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?

This is a simple single-parameter retrieval tool with no output schema. The description adequately summarizes the tool's functionality and return value, covering what an agent needs to know to invoke it correctly.

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 input schema already fully documents the 'icao' parameter with examples (100% coverage). The description adds no additional parameter semantics beyond restating 'airport', so the baseline score of 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 specifies a clear action ('Get the latest METAR') and a specific resource ('an airport'), and distinguishes this from sibling weather tools (e.g., wx_taf, wx_pireps) by naming the METAR product. The return contents are also stated, making the tool's purpose unambiguous.

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 ('when you need a METAR') but gives no explicit guidance on when to prefer this over related tools like wx_taf or wx_pireps. There is no mention of exclusions or alternatives, leaving the agent to infer the use case.

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