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

Discloses behavior well beyond the annotations: it is a live on-chain read, pricing comes from each token's deepest Uniswap v3 pool, the return includes holdings, a total and anything that could not be priced, and the call costs $0.005 USDC on Base via x402. The paid-call mechanic usefully explains the readOnlyHint=false / idempotentHint=false annotations rather than contradicting them. Minor gap: no explicit note on rate limits or failure/refund behavior for failed calls.

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 the resource and value proposition, and each sentence adds information (scope, exclusions, usage, price). The parenthetical token list is slightly dense and run-on, but nothing is wasted.

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 covers the return shape ('holdings, total and anything that could not be priced'), chain coverage, token coverage limits and the payment requirement, which is enough for an agent to call it correctly. Coverage of pricing staleness/rounding is the only material omission.

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%, so the schema already documents address, chain enum values and the comma-separated token list; baseline 3 applies. The description adds useful context on the token parameter (up to 20 addresses, only the common tokens are included by default) but no syntax detail beyond the schema.

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?

Names the specific resource (wallet USD value) and enumerates scope precisely: four chains, native ETH plus named major tokens, up to 20 user-added tokens, priced from deepest Uniswap v3 pools. It explicitly rules out the adjacent resource ('Not a full token inventory') and is clearly distinguishable from sibling token-balance and plain balance 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?

Gives an explicit use context ('check what a wallet is worth before trading, lending or paying') and an implicit negative condition ('Not a full token inventory'), which steers agents toward wallet-audit/token-balance when coverage is needed. It does not name those alternatives outright, so it falls short of a full when/when-not statement.

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