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

Annotations already supply readOnlyHint=true and the description does not contradict it, so the read-only safety profile is covered. However, the description adds no behavioral nuance beyond the tool name; notably, it does not disclose that results are paginated despite the cursor parameter, and it does not describe what the response contains.

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 extremely terse and front-loaded: one sentence with no filler. It could be improved by noting pagination, but as written it is efficiently scannable and 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?

For a simple list retrieval with readOnlyHint=true and a fully documented two-parameter schema, the core invocation is clear. The missing pagination and return-behavior details are a real gap because there is no output schema, and 'all' could reasonably be read as a single unpaginated response; a brief note about cursor paging would make it complete.

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?

The input schema covers 100% of parameters with clear descriptions ('The list ID', 'Pagination cursor'), so the description need not repeat them. The 'all subscribers' phrasing loosely relates to the cursor's purpose but does not add concrete parameter semantics beyond what the schema already provides.

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?

Description states a specific read operation ('Get') on a specific resource ('subscribers of a list'), making it immediately distinguishable from siblings like get_list, get_user_list_subscriptions, and subscribe_user_to_list. The 'all' qualifier adds scope. Minor ambiguity around pagination exists, but the purpose itself is unambiguous.

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 description provides no explicit when-to-use guidance or alternatives, but 'all subscribers of a list' makes the intended use inferable: retrieve subscriber membership for one list. It does not mention exclusions or explicitly distinguish it from related tools like get_user_list_subscriptions or list_audience_members.

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