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

Annotations already declare readOnly/openWorld/non-destructive, so the description's main added value is naming what the payload contains (member count, mailing count, flags) — meaningful since there is no output schema. It omits behavior for a nonexistent or unauthorized id, which keeps it from a 5.

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 front-loaded sentences with no filler; the return fields come first. The trailing 'GET /groups/{id}' is near-redundant with the name but cheap and aids API mapping.

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 tool with full annotation coverage, this is nearly complete: it says what comes back and implies id-scoped lookup. Only the failure mode for an unknown id is left unstated.

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?

Single parameter with 100% schema description coverage ('Cyberimpact group id.', positive integer), so the schema does the work. The description's 'by id' merely confirms the schema's intent rather than adding format or constraint detail.

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 ('One group by id') and enumerates the returned fields (member count, mailing count, flags). It is clearly distinguishable from list_groups by the singular scope, though it never names the sibling explicitly.

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: fetch a single group when you have its id. There is no explicit guidance on when to prefer this over cyberimpact_list_groups or cyberimpact_get_member_groups, and no precondition/error notes.

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