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

Goes well beyond the annotations: travelers see the new price so a wrong price costs money, external booking systems can overwrite the value, confirmation is on by default but toggleable, the call reaches other people, and it requires a Cotlet API key with app access. This is unusually rich disclosure of consequences and auth needs for a mutation tool.

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?

Purpose is front-loaded and the behavioral warnings follow in a usable order. The first and second sentences partly restate each other ('Change the retail price...' / 'Sets the retail price...'), a minor redundancy in an otherwise dense, waste-free block.

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 mutation tool with no output schema, the description covers purpose, overwrite risk, confirmation behavior, blast radius, and auth requirements, which is substantial. It is only slightly short of complete given no return-shape information is needed.

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 the schema itself documents option_id, prices, and valid_from. The description reinforces the per-category and from-a-date semantics but adds no syntax or format detail beyond the schema, so 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?

States a specific verb and resource: 'Change the retail price per category of an option, from a date on,' which is unambiguous. It does not explicitly differentiate from the closest sibling getyourguide_update_availability, which is what would push it to 5.

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?

Provides operational usage context (confirm each call, confirm with the user before each call), which implies when care is needed, but never states when to pick this tool over update_availability or other siblings. Usage is implied rather than spelled out.

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