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

Beyond annotations, the description adds important behavioral context: deterministic/no-LLM execution, a concrete example output, and an explicit payment requirement via x402 in _meta. It does not cover error behavior or rate limits, but it materially improves transparency for an annotated read-only tool.

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?

The description is front-loaded with the core purpose and output fields, and the example and payment note earn their place for a paid tool without an output schema. There is minor redundancy around 'on Base' versus the multi-chain support, but overall it is efficient.

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 simple two-parameter read tool with no output schema, the description supplies the returned fields, an example response, supported chains, and payment instructions. It is nearly complete, though it could clarify error behavior or whether payment is required for non-Base chains too.

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 both the chain and address parameters are already documented in the schema. The description repeats the supported chains but adds no new syntax, format, or constraint details beyond what the schema provides.

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?

The description states a specific resource and scope: a wallet snapshot returning native ETH balance, nonce, and contract status across four chains. This clearly distinguishes it from sibling tools such as base_erc20_balance (token balances) and wallet_portfolio, since it is explicitly limited to native ETH and contract/nonce metadata.

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 description implies when the tool is useful by listing the returned fields and supported chains, but it does not explicitly say when to prefer it over alternatives like base_erc20_balance, wallet_portfolio, or solana_balance. No exclusions or routing guidance are provided.

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