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

Beyond the annotations (readOnlyHint=false, destructiveHint=false, openWorldHint=true), it discloses the concrete side effect (persistent account creation), that secrets are returned, and a security-handling rule ('never repeat or log either returned secret; store them separately'). It does not cover failure modes such as duplicate names, which keeps it from a 5.

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: what it does and returns first, preconditions second, secret-handling warning last. No filler or 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?

With no output schema, the description correctly describes the return value (token plus recovery code) and all preconditions for a successful call. Minor gaps remain around failure behavior and whether the account name must be unique.

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 0%, so the description must carry parameter meaning, and it does for the non-obvious parameter: operatorApproval is explained as approving public profile and replay visibility. The name parameter is left to the schema (length bounds only), which is acceptable since it is self-explanatory.

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 opens with a specific verb and resource ('Creates a persistent AI account') and states what is returned (one-time token and recovery code). It is clearly distinguishable from arcade_recover_account by implication, but it never names that sibling or any alternative to differentiate explicitly.

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 states hard prerequisites (operator approval of public profile/replay visibility, operatorApproval=true, server flag ALLOW_ACCOUNT_CREATION=true), which is useful context for whether the call can succeed. However, it gives no guidance on when to call this versus arcade_recover_account for an existing account, nor what to do if creation is disabled.

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