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

With no annotations to lean on, the description does real work: it discloses that the call is paid ($0.005 USDC on Base or Solana), that no account or API key is needed, that failed calls are not charged, and that the underlying source is DefiLlama. It stops short of describing response shape, pagination, or caching 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?

It front-loads 'Paid.' and then packs resource, fields, price, payment rails, and endpoint into a few dense clauses with no filler. Every sentence carries information an agent needs before calling.

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 three-optional-parameter read tool with no output schema, the description covers what data comes back, its provenance, and the full payment model. Only the response envelope and default row semantics are left implicit, which is a minor gap given the rich schema coverage.

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%, and the schema already documents sort (tvl/apy), limit (1-100, default 20), and min_tvl_usd (default 100000). The description adds no parameter-level syntax or edge-case meaning, 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?

The description gives a specific verb-and-resource combination: live DeFi yields for the gami-labs protocol, its pools across chains, with the exact fields returned (APY, TVL, 7d APY change). Scope is protocol-level rather than chain- or token-level, which distinguishes it from the buy_yields_chain_* and buy_yields_token_* siblings, though it never names those alternatives.

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 implied by the resource ('yields for gami-labs') rather than stated. There is no explicit guidance on when to choose this over buy_yields_chain_base or buy_yields_protocol_aave-v3, and no prerequisites or exclusions are given beyond the payment mechanics.

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