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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds actionable context beyond them: it explicitly tells the agent that invitations and role modifications cannot be done here and must go through the dashboard. That prevents wasted attempts at mutation, which annotations alone would not convey.

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 parenthetical sentence, front-loaded with the resource and role information, with the read-only caveat immediately following. No wasted words.

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 tool with no output schema, the description covers the essential question of what data comes back (people and their roles) and what is out of scope. Slightly short of 5 only because it doesn't hint at ordering, pagination, or which role fields are returned.

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 and the schema is empty at 100% coverage, so there is nothing for the description to document. Baseline 4 applies; no syntax or format details are needed.

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 identifies the resource ('people with access to the agency') and, through the title plus 'their roles', makes the listing intent unambiguous. It is clearly distinguishable from siblings like list_assets or list_clients, though the verb is implied 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?

'read-only; invites and role changes are dashboard-only' sets a useful boundary on what this tool can accomplish, implying use it for inspection only. However, it gives no guidance on choosing it over sibling tools such as get_agency, which likely also exposes member information.

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