busiest_airports

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

With no annotations, the description carries the behavioral disclosure burden, and it does this well: it states that the measurement is observed activity rather than scheduled movements, and it openly warns that airports in poorly covered regions may look quiet. This is genuinely useful caveat information. It does not mention output ordering or pagination, but those are less critical for a ranking query.

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 four concise sentences, each earning its place: the core question, the counting method, the optional filter, and an important data caveat. The most important information is front-loaded and there is 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?

For a read-only ranking tool with two optional parameters and no output schema, the description gives enough behavioral context to call it correctly and interpret the result: global major airports, an optional country filter, and a coverage caveat. It could be more complete by mentioning how the returned list is ordered or how limit affects the response, but it is not a significant gap.

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 description explains the country parameter well with concrete examples like US, GB or IN, which adds value beyond the raw schema. However, it does not explain what limit controls beyond what the name and default value imply, and schema description coverage is 0%, so the description had to compensate more fully than it did.

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 identifies the resource (major airports) and the exact measurement (counts of aircraft on the ground or manoeuvring nearby), so an agent knows what the tool computes. It also explains the optional country filter. It does not explicitly contrast with the closely related sibling airport_activity, so it stops short of perfect sibling differentiation.

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 gives strong context for when the tool is appropriate: asking which major airports currently have the most observed aircraft traffic, optionally within one country. However, it never tells the agent when to prefer this over airport_activity or the other sibling tools, so routing decisions are left to inference.

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