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

With no annotations, the description carries the full burden and it delivers by stating 'Does not move funds or expose keys' and explaining the success flow (wallet linked, session_token, unlock tiers). It also reveals the return shape. It does not mention failure modes or rate limits, but for a verification step the disclosed side effects are sufficient.

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 concise yet rich, fitting essential workflow details, parameter semantics, return fields, and safety guarantees into a few lines. It is front-loaded with the step context, and every sentence adds value without redundancy.

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?

Given no output schema or annotations, the description provides a thorough overview: prerequisites, parameter semantics, expected output, and safety. It lacks explicit error handling or failure scenarios, but for a 5-parameter verification tool, the description is quite complete and leaves no major gaps.

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 0%, so the description must compensate. It does by explaining chain values ('evm' vs 'solana'), the signature format for each, that nonce comes from request_verification_challenge, that the signature must be over that exact challenge text, and that agent_id must be the same as the challenge request. Address is self-explanatory from context, so all parameters gain semantic meaning beyond the bare 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?

The description clearly states it is 'Step 2 of wallet verification: prove control by signing the challenge from step 1.' This gives a specific verb ('sign') and resource ('challenge') and distinguishes it from the sibling tool request_verification_challenge, which is step 1. It also mentions the outcome (wallet linked, session_token) and explicitly states it does not move funds or expose keys.

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 explicitly frames the tool as 'Step 2' and references step 1 (request_verification_challenge), telling users to use the nonce from that challenge and pass the same agent_id. It also explains the downstream use of the session_token with other agents like check_token_safety. However, it does not explicitly state when NOT to use the tool or mention alternatives, which is less critical here given the sequential nature.

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