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

With no annotations, the description carries the full burden and does well: it discloses the paid model, exact price ($0.01 USDC on Base or Solana), that no account or API key is needed, and that failed calls are not charged — a meaningful commercial constraint an agent could not otherwise know. It stops short of describing result shape or ordering 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-loaded with 'Paid.' followed by payload, price, access terms, and endpoint — every sentence carries distinct information with no padding. The telegraphic phrasing ('for save: its pools') is slightly compressed but still parseable.

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-parameter, no-output-schema read tool, the description covers what the data contains, where it comes from, what it costs, and how to access it. Minor gaps remain around pagination or result ordering, but nothing needed to call it correctly is missing.

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%, with each of sort, limit, and min_tvl_usd documented including defaults and ranges. The description adds nothing about parameter meaning, so 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 states a specific resource ('Live DeFi yields for save: its pools across chains') along with the exact returned metrics (APY, TVL, 7d APY change) and the upstream source (DefiLlama). The protocol name 'save' embedded in the tool name and description is what distinguishes it from the many sibling buy_yields_protocol_* tools.

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 infers this is the tool for the Save protocol's pool yields rather than chain-wide or token-wide yields. There is no explicit statement of when to prefer buy_yields_chain_* or buy_yields_token_* instead, and no mention of prerequisites beyond the payment terms.

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