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

With no annotations present, the description carries the full burden and does substantial work: it discloses the paid cost ($0.002 USDC), accepted payment chains (Base or Solana), no account or API key requirement, no charge on failure, and the upstream data source (DefiLlama). It does not describe response shape, freshness, or per-call rate limits, which keeps it below a 5.

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?

Front-loaded with 'Paid' and then the data scope, followed by cost and access terms; there is no filler. The trailing bare URL is slightly clipped but functional, and the sentences each contribute one distinct fact.

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?

For a paid, keyless data endpoint with no annotations and no output schema, the definition covers the essentials an agent needs before spending money: what is returned conceptually, price, payment rails, and failure billing. Missing pieces like pagination behavior and whether sort/limit affect billing are minor given the low complexity.

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 fully documented in the schema including defaults. The description adds nothing beyond alluding to APY and TVL as output fields, which loosely maps to the sort options but gives no extra syntax or edge-case guidance.

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?

States a concrete verb-like scope (where to earn yield) plus the exact resource and constraint: live pools holding KBTC, across protocols and chains, with APY and TVL. The KBTC scoping cleanly separates it from the buy_yields_chain_*, buy_yields_protocol_*, and buy_yields_top siblings without needing to name them.

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?

Usage is only implied: an agent must infer this is the right tool when the target asset is KBTC rather than a chain, protocol, or stablecoin. There is no explicit statement of when to prefer buy_yields_chain_* or buy_yields_protocol_* instead, and no mention of what happens when no pools exist for KBTC.

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