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

Annotations already declare readOnly, idempotent, non-destructive, closed-world. The description adds meaningful context beyond that: it discloses reuse behavior ('reuse a qualifying portable proof') and the specific condition under which a hosted link is produced. This goes past the safety profile the annotations cover.

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 sentences, front-loaded with the core behavior followed by routing conditions. Every sentence carries information, though the density makes it slightly hard to parse on first read.

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?

An output schema exists, so return values need not be explained. For a complex tool with nested objects and six parameters, the description covers routing and key conditions adequately, leaving only minor ambiguity around the 'one next step' concept.

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 the baseline is 3. The description's 'omit the wallet when signed in' merely restates the walletAddress schema description. It adds no syntax, format, or inter-parameter details beyond what the schema already documents.

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 a specific dual purpose: 'Reuse a qualifying portable proof or return the one next step needed to finish verification.' It distinguishes itself from sibling proofable_verify by routing signed-in ownership proofs there. The verb+resource is clear, though the hybrid 'reuse-or-guide' nature is slightly abstract and not tied to a single concrete resource.

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?

It gives explicit conditions: omit the wallet when signed in, continue ownership proofs with proofable_verify, and a hosted link is returned only for outside login/payment/different account. It names the alternative tool and when it applies. Missing an explicit statement of when NOT to use this tool at all.

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