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

With readOnlyHint/openWorldHint already in annotations, the description adds value by disclosing the reference-set size (847), the 'Indicative broker estimate' nature, and the Part 295 broker/not-a-carrier legal context. No contradiction with annotations.

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 core purpose is front-loaded in the first sentence, followed by necessary scope and disclaimer context. A few boilerplate legal caveats take space, but every sentence provides some selection/use-relevant context.

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?

The description covers the tool's purpose, dataset scope, estimation nature, and legal status, while the schema covers all parameters. With no output schema, it would benefit from a bit more on return shape, but the description is otherwise sufficient for correct invocation.

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?

All six parameters are already described in the schema (100% coverage), so the baseline applies. The description clarifies 'field' semantics and the runway filter, but adds little beyond the schema for individual parameters.

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?

States a specific verb ('Find') and resource ('US airport'), with explicit search keys (name, city, ICAO, IATA) and an optional mode (nearby fields filtered by runway length). The scope ('business jet can actually use') also differentiates it from the sibling list_aircraft and check_runway tools.

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 makes the intended use clear: locate US airports or nearby usable fields by identifier/name or runway capability. It does not explicitly name alternatives or exclusion conditions, but the 'find vs. check/quote/list' context is strong enough to guide selection.

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