Book appointment

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

Annotations already convey that this is a non-read-only, non-idempotent, open-world operation. The description adds the prerequisite of checking free slots and clarifies the time format, but does not disclose additional side effects such as conflicts, cancellations, or external calendar behavior.

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 sentences with no filler. The core purpose is front-loaded, and the critical prerequisite and time-format clarification are included without bloating the description.

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 create operation with an existing schema and annotations, the description provides the essential invocation context: what it does, what format the times use, and the recommended preceding tool. It lacks details about return values or optional-field behavior, but those are not required to make a correct call.

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 description adds a concrete ISO 8601 example for startTime/endTime, which is helpful beyond the schema's brief descriptions. However, it does not explain the semantics of required parameters like calendarId or contactId beyond the natural-language context, nor optional fields like assignedUserId or appointmentStatus.

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 states a specific action ('Book an appointment') and the target resource ('on a calendar for a contact'). This clearly separates it from appointment-related siblings like ghl_get_appointment, ghl_update_appointment, and ghl_delete_appointment.

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 explicitly tells the agent to call ghl_get_free_slots first, establishing a clear prerequisite workflow. It does not enumerate when not to use this tool versus update/delete, but the context is strong enough for correct routing.

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