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

Annotations cover the safety profile (readOnlyHint, openWorldHint), and the description adds genuinely non-obvious context: the result is deliberately approximate because v3 uses concentrated liquidity, the data comes from on-chain pool depth, and the call costs 0.0050 USDC and is always billed even on failure. Missing only rate limits or latency expectations.

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?

Three sentences, front-loaded with what is computed and for which pair/venue, followed by accuracy caveat and pricing. No filler or repetition of the title.

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?

With no output schema, the description still conveys the return nature (a price-impact/slippage estimate, approximate by design) and the cost to invoke. It could be slightly more explicit about the return unit (percentage vs. bps), but nothing critical for correct invocation 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% and the single parameter is fully documented there (range 100-5,000,000, default 10000). The description's phrase 'given USD size' restates the schema without adding syntax or format detail, so the baseline of 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: an estimated price impact/slippage for a WETH/USDC trade of a given USD size on Uniswap v3, sourced from on-chain pool depth. This is clearly distinguishable from siblings like token-spot-price, liquidity-health, or dex-arbitrage without opening the schema.

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?

Provides implied usage context ('useful for MEV/execution bots before trading') and a caveat about which signals are appropriate (order-of-magnitude only). However, it never names an alternative tool or states when NOT to use it, leaving the agent to infer routing against the many sibling price/liquidity tools.

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