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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds real value beyond that by disclosing the answers come from a 'researched dataset' rather than live lookups, and that coverage is limited to 'major international airports'.

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 sentences, no filler, with the usage trigger front-loaded before the content description. Every clause earns its place.

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?

An output schema exists, so return values need not be described, and the single parameter is fully documented in schema. The description covers scope and data provenance; the only minor gap is what happens for airports outside the 'major international' set.

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 coverage is 100% for the single airport_code parameter, and the schema itself documents the IATA format with an example. The description adds nothing about the parameter, so the baseline 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?

States a specific verb/scope: answering connectivity questions (Wi-Fi, SIM vendors, eSIM) for an airport, sourced from a researched dataset of major international airports. This clearly separates it from generic siblings like find_free_wifi or lookup_apn_settings. It does not explicitly name those siblings, so it stops short of a 5.

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 opening 'Use when the user asks about connectivity at an airport' gives a clear triggering condition tied to the resource. There is no explicit when-not guidance or named alternative (e.g., use find_free_wifi for non-airport Wi-Fi), so it is solid but not exhaustive.

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