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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: the message must be signed within 10 minutes via EIP-191 personal_sign and consumed by register_agent, and it explains the downstream benefit (Season points with an AI tag). It does not describe what the returned message contains or the failure mode on expiry.

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 tight sentences, front-loaded with the core action and signing standard, then the expiry constraint and the next tool to call. No filler 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 no-output-schema tool, the description implies the return value (the message to sign) and names the follow-up call (register_agent), which is enough for correct invocation. Minor gap: it never explicitly states the shape of the returned message or what an agent should do if the window expires.

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 four parameters (name, wallet, optional url, optional description) are already documented in the schema with patterns and length limits. The description adds no parameter-level detail beyond what the schema provides, so the baseline of 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 and resource ('Builds the exact message an agent's wallet signs') plus the precise signing scheme (EIP-191 personal_sign), which no sibling tool does. An agent can immediately distinguish this from register_agent (the step that consumes the message) and from other get_* siblings.

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?

Explicit sequencing is given: 'Sign within 10 minutes, then call register_agent,' which tells the agent exactly when this tool fits in the flow and what to do next. It stops short of stating when-not to use it or what happens if the 10-minute window lapses, but the context is clear.

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