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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds value by disclosing the returned fields (changeableUntil, refundableUntil, canCancel, cancelReasonRequired) and the series behavior, which goes beyond the schema.

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 concise sentences with no filler. The core purpose and parameter source are front-loaded, and the series detail is appended without unnecessary elaboration.

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 read-only getter with two required parameters and no output schema, the description covers what the tool returns, how the parameters are obtained, and the special series case. Nothing essential is missing for a 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?

The schema only gives minLength constraints, so the description meaningfully explains that id and token come from create_booking or its manageUrl. This provenance is essential for the agent to know how to obtain valid parameter values.

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?

The description specifies the exact action ('Returns a booking'), the resource ('by its id and token'), and the source of those values. It clearly distinguishes this read-only lookup from the mutating sibling tools like cancel_booking_as_invitee and reschedule_booking_as_invitee.

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 states the prerequisite for using the tool: the id and token come from create_booking or its manageUrl. It implies the appropriate context is viewing an existing booking, but it does not explicitly compare against check_series or state when not to use this tool.

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