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

Annotations already declare readOnlyHint=true, so the safety profile is covered; the description reinforces this by naming the underlying GET endpoint. It adds no behavioral context beyond that – no pagination behavior, result caps, or auth requirements. Adequate but thin given annotations do the heavy lifting.

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, with the core purpose and return shape front-loaded before the sequencing hint. The trailing 'Mindbody: GET /appointment/bookableitems' is mildly redundant but useful for API mapping.

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 read-only list tool with no output schema, the description reasonably signals the return shape (staff, location, time windows). It does not describe pagination behavior or how results are grouped, which an agent must infer from the schema, but nothing essential to correct invocation is missing.

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 all 10 parameters are already documented in the schema, including defaults, formats, and semantics. The description only gestures at the filter dimensions (staff, session types, location, time) without adding format or interplay details beyond the schema. 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?

Specific verb ('Find') plus resource ('appointment availability') with an explicit enumeration of what is returned – staff, location, and time windows for the given session types. It distinguishes the tool from mindbody_add_appointment by naming the sequencing relationship, though it does not explicitly contrast with mindbody_list_staff_appointments or mindbody_list_session_types.

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?

Explicit sequencing guidance: 'Use before mindbody_add_appointment.' It also points to mindbody_list_session_types for obtaining session type ids. No when-not guidance is given (e.g., that this is not for listing already-booked appointments, which is a sibling's job).

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