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

Annotations already declare readOnly, idempotent, open-world, and non-destructive behavior. The description adds valuable context beyond that: the link is powered by Stay22, shows Booking.com/Expedia/Agoda/Vrbo, the user books externally, no prices are returned, and a commission may be earned. This clarifies the external, non-transactional nature of the 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?

The description is three sentences and front-loads the core purpose: a link to live prices for a place/town and dates/guests. The second and third sentences add useful behavioral and disclosure context without excess, though the first sentence is slightly overloaded with provider details.

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?

An output schema exists, so there is no need to explain return values. Given annotations, full schema coverage, and the tool's simple link-generation nature, the description covers the key context: external provider, no prices returned, no booking performed, and potential commission. Minor gaps like link expiration or presentation guidance are not essential.

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 all six parameters are already documented with examples and constraints. The description references 'place or any town' and 'given dates and guests,' but adds no syntax, defaults, or edge-case guidance beyond what the schema provides. Baseline 3 is appropriate when 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 clearly states this tool provides a link to live hotel and rental prices for a place or town, naming Stay22 and the booking providers. It is distinguishable from siblings like list_places and tourist_tax, though the phrasing is nominal ('A link to...') rather than an explicit verb like 'generates a booking link'.

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?

Usage is implied: this is for getting a hotel/rental booking link, not for retrieving prices or booking. The description explicitly says 'this tool returns no prices and books nothing,' which helps avoid misuse, but it does not name alternatives, state when-not-to-use conditions, or mention sibling tools that might provide related information.

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