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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. The description adds real behavioral context beyond that: decimals are read on-chain from the token, and the result carries a signed receipt — a non-obvious output trait.

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 that front-loads the operation, the resource, and the chain, then appends the receipt trait. No filler or redundancy.

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?

An output schema exists, so return values need no elaboration, and annotations cover safety and idempotency. Chain scoping and the signed-receipt output are disclosed; minor gaps remain around failure behavior for invalid or non-contract token addresses.

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 coverage is 100%, so all three parameters are already documented, making 3 the baseline. The description adds marginal value by explaining that decimals are read from the token, which contextualizes the optional decimals override, but gives no syntax or format 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?

States a specific verb and resource (balanceOf for an ERC-20 token), pins the chain to Base, and clarifies that both raw and formatted values are returned. It does not explicitly differentiate itself from the sibling balance_check, so it falls just short of a 5.

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 Base/ERC-20 scoping implies when the tool applies, but there is no explicit when-to-use, when-not, or named alternative (e.g., balance_check for native/other-chain balances). Usage must be inferred from the scope statement.

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