x402_yield

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

With no annotations, the description carries the full burden of disclosing behavior. It does not state whether the operation is read-only, what data is returned, or any side effects. The mention of '~5% APY' is informational but not a disclosure of tool behavior.

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 concise, with only two sentences. The first sentence states the purpose and the second provides useful context about automatic APY earning. Every word earns its place with no padding.

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?

Given the simplicity (no parameters, no output schema), the description adequately conveys the tool's core purpose. However, it lacks detail about the exact nature of the returned 'yield information' (e.g., current APY, projected earnings, or historical data), which would be valuable for an agent to set expectations.

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 has zero parameters, so the baseline per the rubric is 4. The description adds no parameter information, but none is needed, making this score 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 tool's function: 'Get yield information for your USDs holdings.' It uses a specific verb and resource, and the added detail about earning ~5% APY helps scope the purpose. However, it doesn't explicitly differentiate from closely related siblings like x402_yield_estimate or usds_yield_history, so it's not a 5.

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 such as usds_yield_balance or x402_apy. It only states what the tool does, leaving the agent without explicit usage context or exclusions.

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