search_airlines

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld; the description adds that data comes from a cached read-only account reference set and that limit is bounded to 1..100. That is real value beyond the structured fields, though it says nothing about result ordering or truncation behavior.

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?

Three short sentences, zero filler, with the core purpose and the important return-value caveat front-loaded.

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?

Output schema exists, so return shape need not be described; the description still surfaces the one returned field an agent must carry forward (airlineId). For a two-parameter read-only search, nothing needed for correct invocation 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 coverage is 0%, so the description must compensate, and it does: it explains the accepted query forms (IATA/ICAO code or name) and the limit range 1..100 that the schema omits. Remainder is minimal for a 2-parameter tool, so this is close to complete for a lightweight search.

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+resource (search airlines) plus the accepted inputs (IATA/ICAO code or name) and the key output (airlineId). This distinguishes it cleanly from sibling lookups like search_flights, search_airports, and search_aircraft_types.

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?

Implies when to call it by noting the returned airlineId is required for flight-number searches, i.e. use this as a prerequisite step. It does not name an explicit alternative or exclusion, but the usage context is clear enough to route correctly.

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