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

Annotations already declare readOnlyHint and destructiveHint=false, so 'Read-only; changes nothing' is largely redundant. The description does add value annotations cannot: the required key scope sites:read, the guarantee that e-mail addresses are never returned, and the null semantics of the name field. That is substantive disclosure beyond structured fields.

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?

Three compact clauses with no waste, and the safety statement is front-loaded. Every sentence contributes either a scope constraint, a field contract, or a downstream usage hint.

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, the description carries the burden of describing the return shape, and it does so field by field, including the negative constraint (never e-mail). Only the relationship to list_members is missing, which keeps it from a 5.

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% and there is a single required parameter whose meaning (site ID from list_sites) is fully documented in the schema. The description adds no further detail about the site argument, so the 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?

The description names the resource precisely – 'the people who reach this site' – and enumerates the returned fields (user_id, name, role, version), so the agent knows what it gets. It never states an explicit verb (list/read) and never contrasts itself with the sibling list_members, so the distinction has to be inferred from 'this site' versus a broader member list.

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 version remove_staff needs' is a real workflow pointer: call this before remove_staff to obtain the version argument. Beyond that there is no when-to-use or when-not-to-use guidance, and the presence of the sibling list_members makes the missing differentiation a genuine gap.

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