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

Adds meaningful context beyond the annotations: it reaches no one (no notification side effect), is reversible in one call, and needs a Cotlet API key with app access. This is real behavioral disclosure on top of readOnlyHint=false/destructiveHint=false/openWorldHint=true. It does not contradict the annotations.

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 core action, but sentence one and sentence two say the same thing ('checked in, or undo' / 'checked in, or not checked in when checked_in is false'). This redundancy costs it a point, though the total length is acceptable.

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 simple idempotent toggle with annotations covering the safety profile and a 100%-documented schema, the description is essentially complete: it explains reversibility, absence of side effects, and auth needs. No output schema is needed for a check-in toggle.

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 booking_id and the checked_in toggle are already documented, including that false undoes the check-in. The description restates the checked_in=false behavior rather than adding syntax or format detail, 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 and resource: 'Mark a booking as checked in, or undo the check-in.' An agent immediately knows the operation. However, it never names or distinguishes itself from siblings like momence_cancel_booking or momence_book_customer, so it falls short of full sibling differentiation.

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?

The description implies when it is safe to run unattended ('runs without asking') but gives no explicit when-to-use versus alternatives routing, nor prerequisites beyond the API key note. Usage is only implied, not stated.

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