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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuine context beyond that: results are capped at 12 options and each option pairs an arrival/departure with available apartment types, which tells the agent the search is fuzzy rather than exact.

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?

Two tight sentences: the action and the example come first, the result shape second, with no filler. Slightly awkward nesting of the quoted example, but nothing is wasted.

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 read-only, fully specified four-parameter search with no output schema, the description covers purpose, an example input, and a summary of the return shape. What remains missing is the sibling differentiation that would let an agent choose confidently between this and check_availability.

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 coverage is 100%, so baseline would be 3, but the description goes further by framing from/to as a search window rather than exact dates and tying nights/persons together in one example query. That clarifies how the four required parameters combine into a single search.

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: search for free stays in a date range, and adds the return shape (up to 12 arrival/departure options with free apartment types). However, it never distinguishes itself from the similarly named sibling check_availability, so an agent must guess which one to pick.

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 example phrasing "a week in July for 4 people" implies a fuzzy search use case, but there is no explicit when-to-use, when-not-to-use, or named alternative. With check_availability in the sibling set, the absence of routing guidance is a real gap.

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