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

No annotations are provided, but the description discloses a critical behavioral trait: it requires a payment of $0.08 via x402 with an X-PAYMENT header, and notes that new wallets get 5 free units. This is vital for the agent to invoke correctly. It also clarifies the ranking methodology (factoring liquidity, volatility, IL, sustainability). It does not mention rate limits or error handling, but the payment disclosure is a significant addition.

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 sentence that front-loads the payment requirement (PREMIUM) before explaining the tool's purpose. It includes the call endpoint and header, which are useful. However, the phrase 'The smart way to compare yields' is marketing fluff that adds little value, slightly reducing conciseness.

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 moderate complexity (4 optional params) and complete schema coverage, the description adequately covers the core purpose, the payment requirement, and the endpoint. It hints at the output (ranked pools) but does not detail the return format. With no output schema, this could be more explicit, but it is sufficient for an agent to understand the tool's behavior.

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?

All 4 parameters have descriptions in the schema (100% coverage), so the baseline is 3. The description adds no additional parameter semantics, such as formatting or default behavior beyond what the schema already states. Therefore, a 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 tool's function: 'APY adjusted for risk — pools ranked by real expected return after factoring liquidity, volatility, IL, and sustainability.' It uses a specific verb (ranks) and identifies the resource (pools), and the emphasis on risk-adjusted returns distinguishes it from sibling tools like top_yields or yield_scan.

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 implies the use case (comparing yields on a risk-adjusted basis) but does not explicitly mention when to use it over alternatives or provide exclusions. Sibling tools are not referenced, so the agent must infer when this tool is appropriate from the purpose alone.

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