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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the shape of the returned record (selling plans and the products they apply to), which is genuinely useful. It says nothing about error behaviour for an unknown id or about permissions/caching.

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 terse fragments with the return payload front-loaded and no filler. The trailing REST endpoint path is mildly redundant but does communicate that this is a direct read of one record.

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?

With one required, fully documented parameter, no output schema and read-only annotations, the description supplies enough: it names the returned sub-resources so the agent knows what payload to expect. Not-found/error semantics are the only notable gap.

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 coverage is 100% and the schema itself explains that the id may be a gId or numeric id and where to get it, so the description does not need to repeat that. The description adds no further parameter meaning, so the baseline 3 applies.

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 the resource precisely and enumerates what comes back (selling plans with name, prepaid orders, gift support, plus applied products), which goes beyond the title. The singular 'One selling plan group' implicitly contrasts with awtomic_list_selling_plan_groups, but the contrast is never made explicit and there is no verb such as 'retrieve' or 'fetch'.

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: it returns a single group, so the agent infers it should call this when it already has an id rather than enumerating. The routing hint to awtomic_list_selling_plan_groups appears in the schema's parameter text, not the description, and there is no explicit 'use when' or 'not for' statement.

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