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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful content context (that results are broken down by aircraft type and include Starlink fleet share), but does not address coverage, pagination, or what happens for an unknown/unserved airline code.

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?

Two tight sentences, with the resource and scope front-loaded and the argument semantics appended as a compact clause. No filler or restatement of the tool name.

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?

With an output schema present, the description need not explain return values, and it correctly focuses on scope and argument format. It is complete enough to invoke correctly; the only gap is sibling differentiation, which is a usage-guidance concern rather than a completeness one.

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 0%, so the description carries the full burden for the single parameter, and it does: 'airline = IATA or ICAO code' tells the agent the accepted identifier formats, which is not present anywhere in the schema. It does not say whether both formats are accepted simultaneously or which is preferred.

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 resource (in-flight Wi-Fi) with a clear scope modifier ('of an airline by aircraft type') and enumerates the returned dimensions (system, speed class, free, Starlink share). It does not explicitly name the sibling flight_wifi, so the fleet-level vs per-flight distinction is left implicit rather than contrasted.

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?

There is no when-to-use or when-not-to-use guidance and no alternative named, despite flight_wifi and airline_profile being obvious siblings. The agent must infer from 'by aircraft type' that this is a fleet-level lookup rather than a per-flight one.

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