sign_message

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

Without annotations, description states it returns a signature and flags EVM restriction. It does not disclose side effects, prerequisites (e.g., wallet connection), or error handling.

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?

Three efficient sentences, directly stating purpose, options, and a key constraint. No superfluous content.

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?

Lacks return value details (e.g., signature format), error scenarios, or network prerequisites. Given the five parameters and nested structure, more context is needed.

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 covers 100% of parameters with descriptions. The description adds context about the two signing modes but does not deepen understanding 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?

Description clearly specifies two signing modes (personal_sign and signTypedData) and returns a signature. It notes that EIP-712 is EVM-only, distinguishing from siblings like sign_transaction and sign_userop.

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?

Describes two use cases but does not provide when-not-to-use or alternatives. The EIP-712 EVM-only hint offers limited guidance.

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