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

Annotations already declare readOnlyHint and openWorldHint, so the description's only burden is added context. The parenthetical about a segment id being 'a campaign recipient together with its list' is cryptic and does not explain pagination, ordering, or what an empty result means.

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 compact sentence with the resource front-loaded. The trailing parenthetical is short but muddies rather than earns its place.

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 parameter and readOnly annotations, little is strictly required, but 'segments' is a domain term the agent cannot resolve and there is no output schema to reveal the return shape. The description leaves the agent guessing what a segment actually is.

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 list_id is documented in the schema with a pointer to laposta_list_lists. The description adds no additional meaning about the parameter, so the baseline of 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 clear verb and resource: list the segments belonging to a mailing list, with list_id as scope. However, it does not distinguish itself from siblings like laposta_list_members or laposta_list_fields, and 'segments' remains undefined in API terms.

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 indication of when an agent should call this rather than laposta_list_members or laposta_list_lists, and no prerequisites or follow-up steps. Usage is only implied by the tool name.

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