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

Annotations already mark the tool as read-only and non-destructive, so the security profile is covered. The description adds valuable behavioral context beyond that: it does NOT create a booking, requires no credit card, and provides both the link and contact details. It does not contradict the 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?

The operational purpose and parameter list are clear and reasonably front-loaded. However, promotional lines such as 'best price guaranteed' and 'Family-run since 1982' add little for an AI agent selecting or invoking the tool. These phrases dilute the description without improving call correctness.

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 an output schema exists and all parameters are explained with formats, examples, and defaults, the description is sufficient for a correct invocation. The main gap is that it does not state whether availability should be checked first via check_availability, or how the generated link behaves when the requested dates are unavailable.

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 0%, so the description carries the full burden for parameters. It compensates well by documenting every parameter: date format for check_in/check_out, example for apartment, comma-separated ages for children, adult default, and allowed language values. This is exactly what the schema itself fails to provide.

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: 'Get a direct booking link for Landhaus Prägant'. It also explicitly clarifies 'This does NOT create a booking — it provides the link and contact details,' which distinguishes it from booking-execution tools and helps it stand apart from sibling tools like check_availability and get_offers.

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 gives helpful context, such as direct booking without commission and no credit card required, and instructs the language parameter to match the conversation language. However, it never explicitly says when to use this tool instead of a sibling such as check_availability or get_offers; the intended routing is only implied by the tool name and purpose.

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