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

With no annotations, the description carries the full behavioral burden and adds important context: it discloses the $0.005 USDC x402 cost on Base and lists the detailed information returned. It does not explicitly state read-only behavior or rate limits, but 'Identify' and 'contract_info' strongly imply a read operation.

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 one dense but well-structured sentence that front-loads the core purpose and then lists the returned dimensions. Every item in the list earns its place by telling the agent what information is available, and the cost disclosure is appended without unnecessary preamble.

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?

Given one simple parameter, no output schema, and no annotations, the description is complete enough for correct invocation. It explicitly lists the kinds of values returned, including EIP-7702 delegation, token standards, proxy implementation/admin, bytecode size, nonce, and ETH balance, so an agent knows what to expect.

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%, and the single 'address' parameter is already documented as 'Any address on Arbitrum One'. The description reinforces the Arbitrum One scope but adds no syntax, formatting, or usage detail beyond the schema, so the baseline of 3 is appropriate.

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 uses a specific verb, 'Identify', and clearly scopes it to an Arbitrum One address. It enumerates the exact distinctions and metadata it returns, including EOA vs contract, token standards, proxy details, bytecode size, nonce, and ETH balance, which makes it easy to distinguish from sibling tools such as wallet balances or token snapshots.

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?

It clearly establishes the usage context: inspect an Arbitrum One address for wallet/contract classification and contract metadata. It does not explicitly name when to prefer sibling tools like arbitrum_wallet_profile or arbitrum_token_snapshot, but the chain and purpose are sufficiently clear to guide selection.

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