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

Annotations supply only destructiveHint=true, so the description carries most of the burden; it does disclose the POST/DELETE endpoint split and that false reverses a prior check-in, which hints at the non-idempotent undo path. It still omits permission/auth requirements, what happens if the booking is already checked in or cancelled, and error behavior for an invalid id.

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?

Two compact sentences led by the action and its two modes, followed by the id source and underlying endpoints. Every clause earns its place; nothing is repeated or padded.

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 two-parameter mutation tool with no output schema, the description covers the action, parameter mapping, id provenance, and API endpoints, which is enough to invoke it correctly. It falls short only on auth/permission context and failure modes, which an agent would otherwise have to discover at runtime.

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 the baseline is 3, but the description adds genuinely new information: the origin of bookingId (momence_list_session_bookings), which the schema does not state. The checkedIn semantics largely restate the schema and add little beyond the boolean mapping.

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?

Names a precise verb (check in / undo check-in) on a precise resource (session booking) and spells out the boolean-to-action mapping. The operation is unambiguous and clearly distinct from siblings like momence_cancel_session_booking, which the agent can rule out without opening either 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?

Gives clear routing context by stating that booking ids come from momence_list_session_bookings, which tells the agent which sibling to call first. It does not, however, state when to use this versus cancel_session_booking or note any preconditions (e.g. booking must not already be cancelled).

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