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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds valuable behavioral context: the 10-minute validity window and the required signing/usage flow, which are not present in the annotations. This enriches the agent's understanding beyond the structured hints.

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 two concise sentences, front-loaded with the core return value and immediately followed by the actionable next steps. Every sentence earns its place, with no fluff or repetition.

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 simple read-only tool with a single parameter, the description fully explains what to do with the result (sign and pass to attest_agent) and the time constraint. No additional information is necessary for an agent to call it correctly, given the annotations and schema already cover safety and parameter details.

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%, and the single parameter 'address' is clearly described as 'Your 0x wallet address' in the schema. The description does not add any further semantics about the parameter format or constraints, so it meets the baseline for well-covered schema without adding extra value.

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 states exactly what the tool does: returns a specific canonical attestation message for the provided address. It names the exact message type and explicitly references the sibling tool attest_agent, making it distinguishable from all other siblings without ambiguity.

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 description gives clear usage context: obtain the message, sign it with EIP-191 personal_sign within 10 minutes, then pass it to attest_agent. This implies the intended workflow and references the follow-up tool, though it doesn't explicitly state when not to use this tool or mention alternatives beyond attest_agent.

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