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

Annotations already mark the tool read-only and idempotent, and the description adds substantial behavioral context: on_request objects return available:null as a normal path, instant vs on_request modes behave differently, hotels return a rooms[] array, price_total includes fees, booking links must not be altered, and loyalty_bonus is credit rather than a discount. No contradiction with annotations exists.

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 long but well-organized into clear sections with uppercase headers and front-loaded core purpose. There is some redundancy, such as repeating that the owner replies personally and that on_request is not a failure, but most sentences carry a distinct behavioral rule. It earns its length given the complexity of the tool.

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?

Given the complexity of instant vs on_request properties, hotel room arrays, price breakdowns, loyalty bonuses, booking links, and language handling, the description is remarkably complete. The output schema exists, so return-value details do not need to be repeated. The only notable omissions are minor parameter details already present in the schema. The agent has enough context to invoke the tool correctly and present results appropriately.

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?

With schema coverage at 50%, the description compensates by explaining that items are capped at 10, property_key comes from search_properties results, dates are the trigger for a real price, and missing dates make price_from only indicative. However, the guests parameter is not mentioned at all, and lang is only implied through the text-language guidance. It adds strong semantics for the most important parameters but leaves a couple to the schema.

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 opens with a specific verb and object: 'Check availability and price for up to 10 properties on given dates.' It directly answers the traveler's question and explicitly distinguishes itself from search_properties, which 'never does' this. An agent can immediately tell what the tool does and how it differs from siblings.

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 description provides explicit when-to-use guidance: call it as soon as the traveler gives dates, never search the web instead, and use the property_key from search_properties results. It also states what to do when dates are missing — ask for dates and then call check_availability — and clarifies that on_request results are not failures. This strongly routes the agent to the correct workflow.

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