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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds one genuinely useful behavioral fact beyond the annotations — that membership spans both human people and their AI agents, and that roles are returned — but says nothing about pagination, empty groups, or what happens when the group does not exist.

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 short sentence with no filler, and the key concept (group membership) is front-loaded. Brevity here borders on under-specification rather than padding, but nothing is wasted.

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 one-parameter read-only tool with no output schema, the description conveys the shape of the result (members with roles) but leaves the group identifier format and result size/pagination unstated. That is the minimum an agent needs to call it correctly, but not enough to call it confidently.

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 0% and the single required parameter 'group' is undocumented. The description mentions 'a group' but never clarifies whether the value is a group name, slug, or numeric ID, so it fails to compensate for the schema gap.

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 phrase 'Who is in a group (people and their AIs), with roles' clearly identifies the resource as group membership and the operation as a read/listing, and it distinguishes itself from mutating siblings like group_remove or group_invite_create. It does not, however, explicitly separate itself from adjacent listing tools such as groups_mine, org_members, team_members or group_invite_info.

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 condition for when to call this versus groups_mine (my groups), group_invite_info (pending invites) or the other *_members tools. The agent must infer usage purely from the tool name and the parenthetical gloss.

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