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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds a meaningful authorization requirement ('You must be a member') and indicates that only active members are returned, which are behavioral traits beyond the annotations.

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?

The description is two short, front-loaded sentences with no filler. Both sentences earn their place: the first states the content, and the second states the access requirement.

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?

This is a simple read-only tool with a rich output schema and annotations, so the description need not explain return values. It covers the core content and membership prerequisite, though it omits any description of the group_id parameter.

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%, so the description must compensate, but it never mentions the required group_id parameter or explains what identifier is expected. The parameter is only implied by the tool name and the phrase 'Group details,' leaving the schema's type and UUID pattern to carry the burden.

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 states the resource ('group') and the specific content returned ('details and its active members'), which is clearer than a bare tautology. It does not explicitly differentiate from sibling tools like list_groups or get_activity, but the scope is specific enough for an agent to understand what this tool retrieves.

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 sentence 'You must be a member' provides a prerequisite for using the tool, which is useful usage context. However, there is no guidance on when to choose this tool over alternatives such as list_groups or get_activity, so usage is only implied.

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