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

Annotations already declare read-only, idempotent, closed-world, non-destructive, so the safety profile is covered. The description still adds real value: it names the upstream source (resort booking system), specifies the money figures exclude tax and fees, and warns that unit counts are omitted — all non-obvious behaviors not carried by 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?

A single front-loaded sentence with a colon-delimited list of return contents; every clause carries information (source, fields, tax caveat, omission caveat). Dense but not padded.

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 must carry return semantics and it does so thoroughly — availability set, average nightly rate, pre-tax total, booking link, and the explicit omission of unit counts. Only the lack of routing guidance against the booking-link sibling keeps it short of full.

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 check_in/check_out formats and the adults bound are already documented. The description reinforces the date-scoping intent but adds nothing about the adults parameter or date-range constraints beyond the schema. Baseline 3 applies.

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 ('Live availability and prices for specific dates from the resort's booking system') and enumerates exactly what is returned: open villas/suites/island, average nightly rate, pre-tax total, and a pre-filled booking link. It does not distinguish itself from the sibling get_booking_link, whose function is partially absorbed by the 'booking link with the dates filled in' clause.

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 implied by 'for specific dates' — an agent can infer it applies to date-bound availability/pricing questions. There is no explicit when-not or routing to alternatives (get_booking_link, submit_inquiry, get_policy), and the one limitation given ('Unit counts are not shown') is a data caveat rather than usage guidance.

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