sns_list_subscriptions_by_topic

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

No annotations are present, so the description carries the full burden. It does not disclose whether the operation is read-only, any side effects, pagination behavior, or required permissions. The phrase 'in LocalStack' is context but does not reveal behavioral traits.

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 concise sentence with no wasted words. It communicates the essential purpose without redundancy.

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?

The tool is simple (one parameter, no output schema), and the description gives the core action. It does not detail the return format or pagination, but for a straightforward list operation with known API semantics, this is mostly sufficient. However, adding a note about what is returned (e.g., subscription ARNs) would improve completeness.

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% (the topicArn parameter has a description 'Topic ARN'). The tool description adds no additional meaning to the parameter, but the baseline is 3 because the schema already documents it adequately.

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 ('List') and the resource ('subscriptions for an SNS topic'), and 'in LocalStack' adds context. This distinguishes it from sibling tools like sns_list_topics, which list topics rather than subscriptions.

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 guidance is provided on when to use this tool versus alternatives. There is no mention of prerequisites, related operations like sns_subscribe or sns_unsubscribe, or scenarios where this tool is appropriate. The description only gives the basic action.

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