List AENA airports

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

No annotations are provided, so the description carries the full burden. It discloses live fetching ('Fetched live, so always current'), which is useful behavioral context. For a simple read-only list tool, this is adequate, though it doesn't detail return formats or potential limitations.

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 two concise sentences. The first sentence front-loads the essential purpose, and the second adds a relevant behavioral note. Every word earns its place with no redundancy.

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 tool's low complexity, zero parameters, and no output schema, the description is complete. It provides the core purpose and the live-fetch detail, which is sufficient for an agent to select and invoke this tool 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 tool has zero parameters, and the schema is empty. As per baseline, with no parameters the description does not need to add parameter information. It correctly notes that the tool lists airports, which aligns with no input requirements.

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 the verb 'List', the resource 'all Spanish airports in the AENA network', and includes specific attributes (IATA/ICAO codes and city). This makes it distinct from sibling tools like search_flights and get_flight, which deal with flights.

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 that this tool is for retrieving airport lists, and given context signals, siblings are flight-related. However, it does not explicitly state when to use this tool over alternatives or mention exclusions. The usage context is clear but not explicit.

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