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

With no annotations, the description carries the full behavioral burden and does so well: it discloses that the endpoint is experimental, sits behind Kasada bot protection, may return rate-limited errors, and depends on an unofficial private API that can briefly fail. It also names the recommended fallback. It lacks details on retry/backoff behavior or result-cache semantics, but the major reliability traits are covered.

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 description is front-loaded with the EXPERIMENTAL warning and the core purpose, then follows with fallback guidance and data-source caveats. Every sentence adds useful information with no repetition or filler.

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?

For a complex external-API search tool with no output schema, the description explains both the return content (fare bundles, prices, flight numbers, times) and the operational risks and fallbacks. Together with the fully documented schema, an agent has enough context to call it correctly and handle failure modes.

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 all nine parameters are fully documented in the schema itself, establishing a baseline of 3. The description reinforces the WDC pricing context but does not add syntax or meaning beyond the schema for individual parameters.

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 and resource: detailed Wizzair flights for exact dates with fare bundles. It enumerates what is included (Basic/WIZZ Go/WIZZ Plus pricing, flight numbers, exact times), which clearly distinguishes it from sibling tools that provide timetables or fare calendars. An agent can tell what this tool returns without opening the 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?

Usage is clearly implied for exact-date searches with detailed fare bundle pricing, and it explicitly names fallback alternatives (wizzair_search_timetable or wizzair_search_fares) when the endpoint is rate-limited. It does not explicitly say when to choose this over wizzair_search_flight_dates or wizzair_search_routes, but the exact-date focus provides sufficient context.

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