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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds meaningful provenance context: MyRealTrip comes from an official API while Trip.com and Agoda are read from search screens (method=screen). It also discloses the deliberate no-'cheapest'-judgement behavior, which is real behavioral information beyond the 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 English sentence is front-loaded and information-dense, but the entire content is then repeated near-verbatim in Korean, doubling the length with no new information for an agent. That duplication dilutes an otherwise tight description.

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 no output schema, the description does the work of explaining what comes back: three seller values as-is plus a 30-day median comparison, with no cheapest ranking. That is nearly complete, though exact response shape or handling of unavailable sellers is left unstated.

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%, so both parameters are already documented in the schema. The description reinforces the fixed same-date methodology but adds no syntax or format detail beyond what the city/all_dates descriptions already provide, so baseline 3 is appropriate.

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 — direct round-trip economy fare from Incheon — plus concrete scope (1 adult, same dates, Friday departure, three named sellers). An agent can distinguish this from get_hotel_prices, get_tours, or get_demand_index without opening any schema.

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?

'For a popular city' hints at applicability but no explicit when/how condition or named alternative is given, and none of the siblings are referenced. The 3-seller same-date constraint is described, but the agent must infer when this tool is the right pick.

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