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

With no annotations, the description carries the full burden and only says 'Search', adding little beyond the name. It fails to disclose notable behaviors such as hidden-city/virtual-interlining support, whether results include prices, how filters affect output, or that this is a read-only query. The description is too anemic for a tool with many behavioral options (e.g., includeHiddenCity, includeVirtualInterlining) that the schema implies but the description omits.

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?

One sentence with no filler; it front-loads the vendor and purpose, then summarizes filter categories. It is concise and readable, but it sacrifices substance for brevity, so it does not quite reach a 5.

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?

A 26-parameter tool without an output schema and with no annotations needs more guidance: return shape, how to combine filters, special Skiplagged features, or when to prefer this over the flexible-date/calendar siblings. The description does not provide enough to select and invoke confidently in complex scenarios.

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 92%, so the heavy lifting is already done by the schema. The description's summary of filters (passengers, fare class, stops, airlines, timing preferences) adds a helpful high-level overview but no specific meaning beyond the schema. Baseline of 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?

The description states a specific verb ('Search') and resource ('Skiplagged for flights between specific locations'), and the filter summary distinguishes it from sibling car/hotel/calendar tools. However, it does not explicitly contrast with flight-related siblings like skiplagged_sk_flex_departure_calendar or skiplagged_sk_destinations_anywhere, so it stops short of full differentiation.

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 phrase 'between specific locations' implies when to use (concrete origin/destination dates) versus open-ended 'anywhere' searches, but no alternatives are named and no exclusions are provided. Context is inferable but not explicitly guided, which is a gap given many flight-related siblings exist.

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