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

Adds real context beyond the readOnlyHint/destructiveHint annotations: paused pages still answer, the window is capped at 14 days, and the `unavailable` result means the calendar could not be reached. The opening 'Read-only; changes nothing' largely restates the annotation, keeping it from a 5.

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?

Dense but front-loaded — the read-only nature and scope come first, then the payload, then the range constraint and edge behavior. Slightly packed with parenthetical asides, but every sentence adds information.

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 by naming the slot fields, time zone, and the `unavailable` sentinel. A brief note on ordering or pagination would complete it, but nothing essential is missing for correct invocation.

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 already 100%, so the baseline is 3; the description earns extra credit by restating the ISO format for from/to and their defaults (now, from + 7 days) and by explaining the 14-day maximum span exposed by 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?

States a specific verb and resource — the open slots of a booking page — and defines the payload (slot start times in UTC plus the resource's time zone). This clearly separates it from status/listing siblings such as booking_status or get_booking_page, which describe pages rather than slots.

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?

Gives concrete usage context: it can be used to verify slots on a paused page before a person publishes it, and it notes the default 7-day window and 14-day cap. It does not explicitly name an alternative tool (e.g., booking_test) or state exclusions, so it stops short of a 5.

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