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

No annotations are provided, so the description carries the full burden. It does add one genuinely useful behavioral trait – cost ('From $0.005 USDC'), signaling a paid x402-style call – but omits whether the operation is read-only, auth requirements, rate limits, and error 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?

A single tight sentence front-loads the scope before the price tag; nothing is wasted. The pricing tail is partly promotional but still carries information, so it just misses a 5.

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 one-parameter, no-output-schema tool the description adequately conveys what comes back (token balances across the listed chains), but with zero annotations and zero schema coverage it leaves the address-format and read-only questions unanswered.

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?

The single address parameter has 0% schema description coverage and the description does not compensate. It never clarifies the address format, which is a real ambiguity because the tool spans EVM chains (Base, Polygon) and Solana, whose address formats differ.

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 ('Token balances in one call') and enumerates exact scope: native + ERC-20 (USDC/USDT/DAI) on Base and Polygon plus all Solana SPL holdings. This clearly separates it from single-chain siblings like balance or solana_token without needing to name them.

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 phrase 'in one call' hints at an efficiency rationale, but there is no explicit when-to-use guidance, no exclusions, and no reference to alternatives such as the 'balance' or 'solana_account' siblings. An agent gets no rule for choosing this over a single-chain tool.

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