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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description's verb 'Read' aligns. The description adds useful context by specifying exactly what is read (ETH, USDC, block height) and the network (Base), going slightly beyond annotation coverage. It does not mention cost or failure modes, but the title hints at the fee and the read-only profile is fully covered.

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 a single, front-loaded sentence with no redundant words. Every element contributes to explaining what the tool does and for whom.

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 one parameter, no output schema, and strong read-only annotations, the description provides the essentials: the input (a Base wallet address) and the expected output components (ETH, USDC, block height). It omits specifics like units or return format, but for a simple read tool these are secondary.

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 0%, so the description must compensate. It implicitly defines the lone `address` parameter as a Base wallet address via 'for a Base wallet,' adding meaning beyond the schema's bare regex pattern. This is sufficient for a single simple parameter, though it could be more explicit about parameter mapping.

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 action ('Read') and precise resources ('native ETH and Circle USDC balances plus current block height') for a defined scope ('a Base wallet'). This clearly distinguishes it from the unrelated sibling tools like check_url and merchant_audit, which operate on different domains.

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 does not explicitly name alternatives or provide when-not-to-use guidance, but the strong contextual cue ('Base wallet') and the unrelated sibling names make the intended use case unambiguous. The context is clear enough that an agent will know this is the correct tool for reading Base wallet balances.

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