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

With no annotations, the description carries the full burden, and it does disclose the auth requirement and that data is real on-chain USDC settlement records. It does not state pagination behavior, ordering, or whether results are read-only (implied by 'list' but not stated), leaving notable gaps for an annotation-free tool.

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 module tag front-loaded and the auth caveat trailing. It is appropriately sized, though the parenthetical '(earnings)' is slightly redundant with 'USDC settlements'.

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?

No output schema and no annotations, so the description should do more, e.g., describe the returned settlement shape or pagination. For a simple one-param list endpoint it is barely adequate but leaves the read semantics and result format to inference.

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% with a single 'limit' param that the schema already documents as 'Default 50, max 200'. The description adds nothing beyond the schema, so the baseline 3 for full coverage 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 states a specific resource ('real on-chain USDC settlements') and clarifies them as 'earnings', so an agent understands this returns settlement data rather than routes or tenant config. However, the listing/aggregation verb is only implied by the name, and it doesn't explicitly distinguish itself from paywall_list_routes beyond the resource noun.

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 only guidance is the prerequisite '(needs PAYWALL_API_KEY)', which is helpful for auth. There is no statement of when to use this versus other paywall list endpoints, nor any conditions on when not to call it.

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