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

Goes meaningfully beyond the single destructiveHint annotation by disclosing the read-modify-write mechanics: the tool fetches the current booking and PUTs it back with only your changes applied, which matters because Bookeo's PUT requires the full booking object. The raw endpoints (GET then PUT /bookings/{bookingNumber}) are also given. It stops short of covering auth/permission needs or whether the change is reversible.

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?

Three tight sentences with zero filler, front-loaded on the mutation scope. The implementation detail about full-booking PUT is placed last, after the agent already knows what the tool does.

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 12-parameter mutation tool with destructiveHint=true and no output schema, the description covers the essential operational risk (whole-booking PUT) plus the schedule/participant/resource change surface. The main remaining gap is that two parameters (externalRef, promotionCodeInput) have no description anywhere and notification side effects are only lightly touched.

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 already 83%, so the schema carries most parameter meaning. The description usefully groups the reschedule parameters (eventId for fixed/fixedCourse vs startTime/endTime for flexibleTime) and calls out externalRef, but adds nothing for promotionCodeInput or the notify flags beyond what the schema already states.

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 an existing booking') and enumerates exactly what can be changed — reschedule via eventId or startTime/endTime, participant counts, options, resources, external reference. It implicitly separates itself from bookeo_create_booking/bookeo_cancel_booking by scoping to 'existing' bookings, but never names those siblings explicitly.

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 rather than stated: you reach for this tool when a booking already exists and must be modified. There is no explicit when-not guidance, no note about when to prefer cancel+recreate over update, and no mention of prerequisites such as needing the bookingNumber from bookeo_get_booking or bookeo_list_bookings.

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