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

Annotations declare readOnlyHint=true, openWorldHint=true, and the description is consistent: it is a simulation/analysis, no state change. Beyond annotations it adds substantive context: the verdict taxonomy (ok/caution/danger/block), that failure is simulated from the caller's wallet, and the x402 pricing model with free invalid input. Missing only details on latency, caching, or what the red-flag payload looks like.

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?

Front-loaded with the core purpose and scope ('Pre-signing check for Base'), then the input modes, then the red-flag list, then the verdict and pricing. Dense but every clause informs; the long red-flag list is the one part that could be trimmed slightly.

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 complex 5-param tool with a nested object and no output schema, the description covers what it returns (plain-words behavior, red flags, verdict) and the pricing model well. It leaves slight ambiguity about overlap with sibling safety tools, but nothing needed to call it correctly is absent.

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 all five parameters including the nested typedData object are documented in the schema itself. The description restates the top-level fields (to, data, value, from) and mentions typed-data as an alternative input, but adds no semantics beyond the schema, so baseline 3 applies.

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+resource: a pre-signing check for Base transactions or EIP-712 typed-data signatures, returning plain-words behavior plus red flags. The enumerated detection categories (unlimited approvals, NFT approve-all, OFAC/scam counterparties, failing calls) make it clearly distinct from siblings like chain_tx, token_safety_check, or wallet_sanctions_check.

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 phrase 'Pre-signing check' plus 'Send a transaction... or a typed-data signature request' tells the agent the context of use and the two input modes. It also names list_prices as the pricing reference. It does not state when to prefer this over overlapping tools (token_safety_check, wallet_sanctions_check) or exclusions, so it stops short of a 5.

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