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

Beyond the readOnly/idempotent annotations it discloses upstream call costs (1-2 calls for profiles/memberships across all clients, 1 per client for services/contracts and for visits/schedule, capped around 30), that contracts are slow because Mindbody returns full contract text, and that a failed section surfaces under "errors" without losing the rest. This partial-failure and cost disclosure is exactly the kind of context annotations cannot carry.

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?

Front-loaded with what is returned, then cost, then alternatives – a sensible order with no filler sentences. It is dense in a single block, and the Mindbody call-count details are heavy, but every sentence carries actionable information.

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 5-parameter aggregate read with no output schema, the description covers the returned sections, the optional heavy section, the caller's control over scope, and partial-failure behavior. An agent can call it correctly and interpret results without further documentation.

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 the schema already explains siteId, include, clientIds, visitsLimit and scheduleDays including defaults and ranges. The description only reinforces the default section set and echoes the slow-contracts caveat that the schema already states, so it adds little new meaning.

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?

Names a specific resource (one or more clients, up to 10) and enumerates exactly what is returned: profile and balance, memberships, pricing options with sessions remaining, visits, bookings, and optionally contracts/autopay. It clearly separates itself from find_client and clients_at_risk, which are for locating clients rather than reading them.

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 says to prefer this over reading visits, memberships, contracts or bookings one client and one endpoint at a time, and routes discovery workflows to find_client or clients_at_risk. It also gives a positive usage rule: ask only for the sections you need.

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