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

Annotations only carry generic readOnly/destructive/openWorld hints; the description supplies the real behavioral load: identical message returned for the same wallet within a short window, only one pending challenge per wallet, no auth side effect, and explicit rate limits (10/min, one per 6s). It even preempts the 'this looks like a caching bug' misread.

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?

Dense but front-loaded, with the deprecation marker, the purpose, the signing requirement, and the caching caveat in descending order of importance. Every sentence carries information, though the caching/rate-limit passage is lengthy enough to be trimmed slightly.

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?

With no output schema, the description still names the returned `message` field and explains exactly what must be done with it. Combined with the dependency ordering and rate limits, an agent has everything needed to call this correctly and chain it into submit_auth_verify.

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%, so baseline is 3; the description goes beyond it by clarifying that `chain` does not affect which cached message is returned and does not need to match the value passed to submit_auth_verify. It adds genuine semantic value about a parameter's non-effect rather than restating the 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?

States a specific verb+resource (issue a SIWE challenge message for a wallet) and explicitly bounds it: 'Does NOT itself authenticate anything.' It also names the downstream sibling (submit_auth_verify), so an agent can distinguish it from the other auth/submit tools without opening a schema. The [DEPRECATED] prefix is front-loaded.

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?

Gives explicit when-to-use ('required before any deposit/withdrawal/config-update tool') and names the follow-up call (submit_auth_verify with a personal_sign/EIP-191 signature). The main gap is that a deprecated tool does not point to its replacement, so an agent knows to avoid it but not what to use instead.

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