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

With no annotations, the description carries the burden and does well: it discloses the return content (a message plus timestamp), the ~1 hour validity window, and that it never signs anything. It omits what the caller does with the signed message (the submit step), which is a meaningful gap in a no-annotation tool.

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 step and purpose, then the branch conditions, then a safety clarification. No filler.

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?

No output schema or annotations exist, so the description must (and largely does) cover the return value, validity, and per-action requirements. It stops short of describing the downstream step that consumes the signature.

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 already 75%, but the description adds conditional meaning by binding wallet to api_key and name/endpoint_url to register, clarifying which params apply to which enum branch beyond the flat schema descriptions.

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: returns the exact message the caller must sign (EIP-191 personal_sign) plus a timestamp. The 'Step 1 of self-onboarding' framing positions it distinctly from write siblings like registry_create_api_key and registry_register_tool.

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?

Explicitly routes between the two actions: action=api_key (needs wallet) for a free API key, action=register (needs name and endpoint_url) to list a tool. That is clear when-to-use guidance, though it never names the follow-up tool or states when not to use this one.

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