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

Annotations only declare readOnlyHint and openWorldHint; the description adds real behavioral context beyond them: the pay-per-call cost (0.0040 USDC, always paid) and the fact that only a curated token list is covered, so exotic holdings are omitted. It also states the valuation method (on-chain Uniswap v3). It does not address behavior for empty wallets or unsupported tokens, keeping it short of a 5.

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?

Two sentences, front-loaded with scope and coverage before cost and return shape. Dense but every clause carries information; the parenthetical token list is long but necessary to define the coverage limit.

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 compensates by naming the return shape (per-token amounts, USD values, total). Chain scope, token coverage, valuation source, and price are all present, leaving only edge-case behavior (empty wallet, unpriced tokens) unspecified.

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% for the single userAddress parameter, so the baseline is 3. The description's only added nuance is that the address is expected to be a Base wallet, which is marginal beyond the schema's own format hint.

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 resource (a wallet's portfolio on Base) with an explicit component list (native ETH plus USDC, WETH, cbETH, cbBTC, DAI, USDbC) and the valuation source. This cleanly separates it from the price-oriented siblings (token-spot-price, multi-token-price) and from whale-wallet-tracker, which implies monitoring rather than a one-shot snapshot.

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?

The chain scope (Base), the curated token set, and the explicit cost make the intended use case inferable, but the description never states when to pick this over token-spot-price or multi-token-price, nor any exclusions (e.g. non-Base addresses). Usage is implied rather than directed.

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