lookup_airlines

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is fully covered without description help. The description adds only routing context, disclosing nothing about result caps, dataset ordering, or locale-dependent output beyond what the schema states. Adequate but adds little behavioral value.

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 paragraphs; the capability statement is front-loaded and the sibling routing follows, with zero filler. Every sentence 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 explained, and the annotations carry the safety semantics. With all three parameters documented in the schema and clear routing, nothing an agent needs to invoke this correctly is missing.

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 100%: search (name substring or exact IATA), locale, and limit are all documented in the schema with examples and defaults. The description's mention of 'name or IATA code' restates the search parameter rather than adding syntax or edge-case guidance, so the baseline 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 and resource ('Look up airlines') plus the two lookup keys (name or IATA code), immediately telling the agent what entity this resolves. It is clearly distinguished from lookup_airports, lookup_cities, lookup_countries, and search_flights, all of which are named explicitly.

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?

Gives the triggering condition ('user asks which airline a code belongs to, or wants the IATA code for an airline name') and routes the agent away from this tool for airports, cities, countries, and fares by naming the correct alternatives. Nothing about when-not-to-use is left to inference.

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