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

With no annotations at all, the description does real work: it discloses the paid model ($0.002 USDC on Base or Solana), that no account or API key is needed, and that failed calls are not charged — all decision-relevant for a metered endpoint. It stops short of describing rate limits, caching freshness, or response/pagination 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?

Front-loads the 'Paid.' flag, then data scope, then price/auth terms, then the raw endpoint URL. Dense and mostly waste-free, though the bare URL line reads as an artifact rather than information an agent can act on.

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 3-optional-param read tool with no output schema, the definition covers what is returned, what it costs, and what auth is needed — enough to call correctly. It lacks only the response envelope/pagination shape, which is a minor gap since limit is documented in the schema.

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 in the schema. The description adds no syntax, format, or interaction detail beyond what the schema provides, so the baseline 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?

States a specific verb+resource (live DeFi yields for the Beefy protocol) and enumerates the returned fields (APY, TVL, 7d APY change) plus the upstream source (DefiLlama). 'Its pools across chains' implicitly separates it from the buy_yields_chain_* siblings, but it never names a sibling or states the protocol-vs-chain distinction explicitly.

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 can infer this is the tool for Beefy pool yields, and the price line functions as a cost gate for deciding whether to call at all. There is no explicit when-to-use/when-not guidance and no pointer to the chain-scoped or token-scoped yield siblings for different framings.

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