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

Annotations already declare the safe read-only profile, and the description usefully adds two pieces of context beyond them: the shape of the returned data (weekly hours + offered services) and an auth requirement ('Needs the user's Cotlet API key with access to this app'). It stops short of disclosure on pagination or freshness of the schedule data.

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?

The first two sentences say nearly the same thing ('Staff members with their working hours and the services they offer' vs. 'Returns your staff members with their weekly working hours and the services each one offers'), so one sentence is largely wasted. The auth and staff-ID guidance is front-loaded well and earns its place.

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 parameterless, read-only list tool with no output schema, the definition covers purpose, returned fields, auth requirement, and how the returned ID is consumed, which is enough to call it correctly. Missing pagination or volume expectations for what could be a large staff list.

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 tool takes zero parameters, which is the baseline-4 case; there is nothing for the description to disambiguate. The description correctly implies a no-argument, whole-account listing rather than introducing filter concepts the schema cannot support.

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 gives a specific verb and resource ('Returns your staff members') and enumerates the payload (weekly working hours, services each one offers), which separates it from booksy_list_services and booksy_list_clients. It never names those siblings explicitly, so the differentiation is inferred rather than stated.

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?

'Use the staff ID in other tools' clarifies downstream usage but is the only guidance offered. There is no explicit when-to-call-this statement, no prerequisites section, and no comparison against alternative list tools, leaving usage largely implied.

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