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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds genuine context beyond them by disclosing what comes back: live availability, an exact total price per apartment type, and a guest-ready booking link. It omits anything about rate limits, authentication, or the response when no apartment is available.

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 tight sentence with no filler, and the most decision-relevant element (real-time availability and exact total price) is front-loaded. Every clause carries information an agent needs.

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 properly compensates by naming the three return elements an agent must know about, which is the right call for a five-parameter read tool. What remains missing is edge-case behavior, such as what is returned when nothing is available or how multiple apartment types are surfaced.

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 80%, with arrival/departure formats, children age ceiling, and language default all documented in the schema itself. The description adds nothing about parameter semantics, though it does implicitly tie the call to dates and party composition. Baseline 3 is appropriate given the schema does the heavy lifting.

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 pairs a specific verb with a concrete resource and enumerates the deliverables: real-time availability, exact total price per apartment type, and a pre-filled booking link. An agent immediately knows what the call produces. It stops short of differentiating itself from the sibling find_available_dates, which could be confused with this tool.

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 'for given dates' implies the tool is used when the guest already has concrete arrival/departure dates, and 'pre-filled booking link for the guest' hints at a conversion step. However, there is no explicit when-to-use versus when-not, and no routing to find_available_dates for open-ended date discovery or to send_inquiry for follow-up.

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