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

The readOnlyHint annotation already establishes this as a safe read, so the description carries a lighter burden. It adds some value by disclosing what the response contains (role, locations, contact details, bookable status), but says nothing about pagination defaults or rate/scale behavior beyond what the schema already covers.

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?

A single front-loaded sentence that leads with the verb and resource, then the returned fields, then the filter clause. The trailing 'GraphQL: staff' is implementation context that may help mapping but is slightly extraneous.

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?

With no output schema, naming the fields returned is genuinely useful and covers the main gap. Combined with 100% schema coverage for parameters and the readOnly annotation, the definition is complete enough to call correctly.

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 three parameters (after, first, query) are fully documented in the schema itself. The description's mention of 'optionally filtered by a query' adds no syntax or semantic detail beyond that, so the baseline 3 is correct.

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+resource ('List staff members') and enumerates the returned attributes (role, locations, contact details, bookable-online status). It is clearly distinct from the other list_* siblings (clients, appointments, services), though it does not explicitly contrast with 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?

The only usage hint is 'optionally filtered by a query,' which restates the schema's query parameter rather than giving when/when-not guidance. There is no mention of pagination context, prerequisites, or when another tool would be preferable.

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