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

Adds real context beyond annotations: it discloses the two return branches and the fact that agent-readiness data only exists when the site has been probed. Annotations already declare readOnly/no-destructive, and nothing here contradicts them. It stops short of saying what happens on an unresolvable or failed lookup.

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?

Front-loaded with the call trigger before the payoff, which is the right order. The second sentence is dense and slightly wordy ("the kinds of surface an agent can use there"), but every clause carries information about inputs or returns.

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 carries the return-value burden and does so for both hotel classes, including the conditional nature of probe data. Nothing an agent needs to invoke this one-parameter read correctly is missing.

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 coverage is 100% and the single parameter is already documented, so the baseline is 3. The description goes further by restating that the input is a domain or URL, not a name, and by tying that input to the two output shapes, which clarifies what a valid value buys you.

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 (resolve a hotel website), then spells out the two possible answer shapes: a VibeBooking hotel id plus agent page, or an external hotel's own site. It names the siblings that consume its output (get_hotel, get_rates, book_link), distinguishing it from them without the agent opening any schema.

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?

Explicit trigger: "Call this whenever the user gives you, or your web search finds, a hotel's website." It also states the negative condition — "A hotel name alone cannot be resolved: find its website first" — so the agent knows not to call it with just a name.

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