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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description usefully adds the scope constraint ('the workspace authorised by this connection'), implying results are limited by the caller's authorisation, but it says nothing about pagination, ordering, or result limits.

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 identifies the resource, the returned fields, and the access scope with zero filler. Nothing is padded or repeated from the title.

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 zero-parameter read-only listing with an output schema and full annotation coverage, the description is essentially sufficient. The only minor gap is that it doesn't state whether the list can be large or paginated, but the output schema can carry that.

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, so the baseline is 4. There is nothing for the description to disambiguate and it correctly avoids inventing parameter semantics that do not exist.

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 ('List') and resource ('the people and their roles in the Twelfth workspace'), so an agent knows exactly what the tool returns. It adds scope ('authorised by this connection') but does not explicitly differentiate itself from the nearby sibling twelfth_get_workspace, so it stops short of a 5.

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?

There is no stated when-to-use guidance, no prerequisites, and no mention of the obvious alternative (twelfth_get_workspace) or how this differs from other twelfth_list_* tools. Usage is only inferable from the name, which is no guidance at all.

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