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

With no annotations, the description carries the full burden well: it discloses cursor pagination, the exact x402 cost (0.001 USDC per call), and what each result contains (APY, TVL, tokens, vault address). It does not detail rate limits or failure behavior, but the payment model and return shape are clearly surfaced.

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?

Five tight sentences, front-loaded with purpose then filters, output, pagination, and pricing. No filler; every clause conveys actionable information.

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 7-parameter tool with no output schema, the description adequately explains return values, pagination, and the x402 payment flow (reinforced in the schema's paymentProof field). The chief gap is the phantom minimum-TVL filter, which slightly undermines completeness.

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 coverage is 71% and the description adds filter semantics for chainId, asset, and protocol. However it advertises a 'minimum TVL' filter that does not exist in the schema (only sortBy apy/tvl is present), which introduces a mismatch that could mislead an agent into passing a nonexistent parameter.

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 and resource ('Lists transactional DeFi vaults') with scope ('across EVM chains via LI.FI Earn') and links to the sibling earn_deposit tool that consumes its output. An agent can immediately distinguish this from generic TVL tools like chain_tvl or protocol_tvl.

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?

Names the filtering dimensions and explicitly frames the output as the prerequisite for the earn-deposit tool, giving clear usage context. It stops short of stating when NOT to use it or contrasting it with the TVL/analytics siblings, so not a full 5.

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