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

Annotations only supply destructiveHint=true, so the description carries most of the load and does so well: it discloses that unset fields are left untouched, that cross_regional_update defaults to true and propagates writes to other sites, and that test=true commits nothing. It does not say whether fields can be cleared, nor what permissions/errors to expect, leaving a real gap for a destructive mutation.

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?

Four compact sentences, front-loaded with the mutation contract before defaults and the dry-run escape hatch. The trailing 'Mindbody: POST /client/updateclient' line is mildly useful for API mapping but is the one element that does not help an agent decide or call.

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 23-parameter destructive update with no output schema, the description covers the essentials: which fields mutate, the site-propagation default, and a safe validate-only path. It leaves open field-clearing behavior and failure/permission conditions, which is a modest but real omission.

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% across all 23 parameters, so the baseline is 3. The description's parameter-level claims (cross_regional_update default, test dry-run) largely restate what the schema descriptions already say, and 'no card or billing data is accepted' documents an absence rather than adding usable semantics.

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 ('Update fields on an existing client record') and immediately pins down the patch semantics with 'only the fields you pass change.' The phrase 'existing client record' implicitly separates it from the sibling mindbody_add_client, so an agent can route 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 operational guidance: partial-update behavior, a dry-run via 'test: true', and the default-on cross-regional propagation. It never explicitly states when to prefer this over update-adjacent siblings or what prerequisites (permissions, client existence) must hold, so it falls short of the top band.

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