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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=true), so the bar is lower. The description adds a genuine disclosure beyond structured data: that names and emails are personal data, which signals handling constraints. It does not mention pagination limits or rate limits, but the privacy warning is meaningful added context.

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?

Two tight sentences with the returned-field list and the privacy note front-loaded, plus the endpoint. Nothing is padded, though the enum list inside the prose ('teacher, student, admin') slightly duplicates the schema.

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 5 optional filter parameters, no output schema, and no required params, the description carries the burden of describing the response, and it does so by enumerating the returned fields. The main gap is the absence of any guidance on how the filters combine.

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 documents page, role, search, space_ids and session_ids. The description adds no syntax, format, or interaction detail for these filters, so the baseline of 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?

States a specific verb and resource ('List the organisation's users') and enumerates the returned fields (id, name, email, role, active state, external id), which goes beyond a bare restatement of the title. It does not explicitly differentiate itself from siblings, though the user/org scope is distinct from list_sessions/list_spaces.

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?

Usage is only implied: 'List the organisation's users' with a trailing endpoint. There is no statement of when to prefer this tool, no note on combining filters, and no mention of alternatives (e.g. whether a single-user fetch exists among siblings).

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