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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds behavior annotations can't express: it returns up to three ranked proposals (nearest to farthest) and includes all-inclusive pricing, which tells the agent what to expect back.

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 tight sentences, front-loaded with the resource and the fallback trigger, then the return shape. No filler, though the 'sixteen rooms, two days' anecdote is more color than essential instruction.

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 steps in to describe the return value (max three proposals, ordered, with total price) and the fallback context, while annotations cover safety. Only minor gaps remain, such as what happens when nothing is found within a reasonable window.

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%, with each of the three parameters documented in French including the adults default, so the schema carries the burden. The description only implies that start/end define the 'same duration' window and adds no syntax or format detail beyond the schema, making the 3 baseline correct.

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 concrete resource — stays of the same duration near the requested dates that are genuinely available — and frames its output (up to three proposals). It distinguishes itself from create_booking_session by naming that sibling as its fallback trigger, so an agent can tell them apart without opening either 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?

Gives an explicit trigger: use it when create_booking_session returns nothing, and reinforces this with the concrete 'two days of shift often suffice across sixteen rooms' heuristic. It doesn't state when NOT to use it (e.g. when exact dates are mandatory), so it stops short of the full when/when-not/alternatives trio.

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