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

Annotations already declare readOnlyHint=true, so the description need not state that it is read-only. However, it adds no additional behavioral context such as pagination behavior or details about the return payload. While it does not contradict annotations, it also fails to disclose anything beyond what the name and annotation imply, offering minimal added transparency.

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 a single, succinct sentence that front-loads the core action and scope. It contains no wasted words and is easy to parse quickly. The structure is optimal for a simple read operation.

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 GET with two parameters and no output schema, the description is mostly adequate. However, it does not explicitly mention that results are paginated (implied by the cursor) or clarify what a 'list subscription' entails. Some additional context about pagination would improve completeness, but the description is not severely lacking.

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 description coverage is 100% for both parameters (user_id and cursor), so the schema already documents their purpose. The description adds no extra meaning about these parameters, such as how the cursor controls pagination or any format constraints. With the schema carrying the full parameter documentation, a baseline score of 3 is appropriate.

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?

The description clearly states the action ('Get') and the resource ('all list subscriptions for a user'). This distinguishes it from sibling tools that manage or delete subscriptions, such as subscribe_user_to_list or delete_user_list_subscriptions. The phrasing 'for a user' disambiguates from get_list_subscribers, which is about subscribers of a list.

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 guidance on when to use this tool versus alternatives. There is no mention of when to choose this over get_list_subscribers or any other read tool. It only restates the action, leaving the agent to infer the appropriate context without supporting clues.

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