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 only the bare API route and says nothing about error behavior for an unknown id, pagination, or what a returned list contains — no value beyond structured fields.

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, front-loaded with the resource identification and then the route. Nothing is wasted, though the extreme terseness sits close to under-specification rather than optimal concision.

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 trivial one-parameter read with full schema coverage and clear read-only annotations, the description is minimally sufficient. However, with no output schema present, the description should say something about the returned list object and error case for a missing id, and it does not.

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?

There is a single parameter with 100% schema description coverage ('iContact list id.'), so the schema carries the semantics. The description's 'by id' merely restates the required list_id without adding format, range, or sourcing guidance; 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 a specific verb-resource-and-scope: a single mailing list fetched by id, plus the underlying endpoint GET /lists/{listId}. The singular framing implicitly contrasts with the sibling icontact_list_lists, though it never names that alternative 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?

No statement of when to use this versus icontact_list_lists or other get_* siblings, and no prerequisites (e.g. needing a known list id first). Usage is left entirely to inference from the name and the 'by id' phrasing.

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