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

Goes beyond the readOnlyHint/openWorldHint annotations by disclosing the per-call cost ($0.002 USDC via x402), the SIWE domain/nonce/expiry validation behavior, and ERC-1271/ERC-6492 smart-contract wallet support. It does not describe failure behavior or error semantics, so it stops short of a 5.

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?

Two dense, front-loaded sentences: the capability and supported standards come first, then behavioral facts (contract-wallet support, cost). No filler or redundant restatement of the name/title.

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 no output schema, the description should ideally indicate the return shape (e.g., a valid/invalid verdict), which it omits. Otherwise it is well-rounded for an 8-param, nested-object tool: it covers modes, safety profile context, cost, and wallet-type handling.

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 only 50%, and the description compensates partially: it clarifies that 'siwe' expects a full EIP-4361 message including domain, nonce and expiry (mapping to the domain/nonce params), and that typed data follows EIP-712. The remaining params (chain, address, message, signature) get no added meaning 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 precise verb+resource ('Verify a wallet signature') and enumerates the exact standards it handles (EIP-191 personal_sign, EIP-712 typed data, EIP-4361 SIWE). This is clearly distinguishable from sibling address-verification tools like address_verify, which check addresses rather than signatures.

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 message-type enumeration implies when the tool applies (you have a personal_sign, typed data, or SIWE payload), which is useful selection context. However, it never names an alternative tool or states when NOT to use this one, so usage is only implied rather than explicit.

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