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

With no annotations, the description carries the load and does well: it discloses the data source (computed from contract state), the reward exclusion caveat, the block pinning, and the payment model ("$0.0045 USDC (Base or Solana) via x402"). It stops short of stating rate limits, caching, or failure behavior beyond the schema's 400 note.

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 trigger ('Use when...') then Input/Output/caveats, which is the right order. It is dense but mostly earns its space; the trailing price sentence is awkwardly fused with the example and reads as an afterthought.

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?

No output schema exists, and the description compensates by enumerating every returned field (supply/borrow APY, utilization, supplied/borrowed, TVL, block) plus the sort key. Input space, cost, and caveats are all covered; only freshness/refresh cadence and aggregation semantics (e.g., is TVL per market or summed) are unstated.

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 100% and both parameters carry their own descriptions including the 400-before-payment behavior, so the description adds little beyond restating the allowed protocol and asset values. The '?asset=USDC' example is illustrative but redundant with the schema's 'default all' note. Baseline 3 is appropriate.

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 — 'compare lending yields on Base' — and enumerates the exact protocols (Aave v3, Compound v3, Morpho, Moonwell) and assets covered. No sibling tool in the list touches DeFi lending yields, so the boundary is unambiguous.

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?

'Use when an agent must compare lending yields on Base' gives a clear triggering condition, and 'base rates, rewards excluded; not advice' frames the scope. There is no explicit when-not clause or named alternative, but no plausible sibling overlaps, so the gap is minor.

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