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

With no annotations supplied the description carries the full burden, and it does well: it discloses that the call is paid ($0.005 USDC on Base or Solana), requires no account or API key, and that failed calls are not charged, plus the upstream data source. It does not describe rate limits, response shape, or what happens on partial data, leaving some operational gaps.

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?

Dense and front-loaded: purpose first, then source, then pricing and access terms, then endpoint URL. The pricing/auth sentences are slightly run-on comma fragments, but every clause carries information an agent or its payer needs.

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?

Covers the essentials for a 3-optional-param paid lookup: what it returns, where the data comes from, cost, payment rails, and the endpoint. Since there is no output schema, a brief note on the response fields and row/pagination behavior would make it fully self-contained.

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%, so sort, limit, and min_tvl_usd are already fully documented with defaults and ranges. The description adds no syntax or semantic detail beyond that, so the baseline of 3 applies.

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?

Names a specific verb+resource: live yield pools holding STETH, with APY and TVL from DefiLlama, across protocols and chains. This clearly separates it from sibling token tools such as buy_yields_token_wsteth and from the chain/protocol yield siblings without needing to open a schema.

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?

Gives clear context for when the tool applies (wanting yield opportunities on STETH specifically) and implicitly routes other queries elsewhere via the token-specific naming. It stops short of explicitly naming alternatives such as buy_yields_protocol_* for a protocol-centric view or buy_yields_stablecoins for other assets, so exclusions are inferred rather than stated.

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