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

Despite annotations already covering the safety profile (readOnlyHint false, destructiveHint false, openWorldHint true), the description adds real behavioral context: checkout marks the room as needing cleaning and bookable again, no guest is reached, the change is reversible with one more call, and it proceeds without confirmation. That is substantial disclosure beyond the structured fields.

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-loads the core purpose and effect, then adds operational notes. Slightly verbose with a colloquial comparison ('like the status drop-down') and a minor typo ('Cotlet'), but nearly every sentence carries useful 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?

For a mutation tool with no output schema, the description covers the key unknowns: side effects on the room, reversibility, absence of guest notification, and the API-key requirement. Little is missing; only explicit sibling routing and return expectations are absent.

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% and both parameters are already documented with the enum values and the reservation_id format. The description only restates the statuses, adding no syntax or meaning 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 (set/update status) and resource (reservation) and enumerates the three target statuses (confirmed, checked_in, checked_out). An agent can distinguish this from siblings like cancel_reservation or get_reservation without opening the 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?

Explicitly describes when to use it — check a guest in/out or revert to Confirmed — and notes it runs without asking first. It does not name alternative tools (e.g. cancel_reservation) or state exclusions, so it falls short of full when/when-not routing.

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