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

Annotations only supply destructiveHint=true, so the description carries the rest and does it well: no card is charged, apply_payment only applies an existing pricing option and defaults to true, test:true is a dry-run, and a staff user token is required. That is exactly the billing/auth behavior an agent needs before committing a write.

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?

Five tightly packed sentences with the core action front-loaded and prerequisites, billing, and dry-run notes following in priority order. The trailing 'Mindbody: POST /appointment/addappointment' endpoint reference is the one mildly expendable clause.

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 14-parameter mutation tool with no output schema and only a destructiveHint annotation, the description covers the critical unknowns (auth token, dry-run, billing side effects, prerequisite lookup). It does not touch return values or waitlist behavior, but the essentials for correct invocation are present.

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 coverage is 100%, so the baseline is 3, but the description goes beyond the schema by clarifying that no card is charged and that apply_payment is limited to pricing options already on the client's account, plus restating dry-run semantics for test. Marginal but real added meaning over the structured fields.

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 plus the actors involved ('Book an appointment for a client with a staff member at a location'), which cleanly distinguishes it from mindbody_update_appointment, mindbody_list_staff_appointments, and mindbody_add_client_to_class.

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 routes the agent to mindbody_list_bookable_items as the prerequisite slot-finding step, which is the main usage decision. It stops short of stating when not to use this tool (e.g. reschedule vs update), so it is clear context without full exclusions.

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