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

Despite annotations being minimal (readOnlyHint: false and destructiveHint: false), the description fully discloses the important behavior: it deducts from the account balance, initializes DNS asynchronously, can temporarily report a missing zone, and returns an actionId rather than completing immediately. This significantly exceeds what annotations provide and prevents serious user-visible surprises.

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 compact yet information-dense: it states the action, side effect, asynchronous DNS behavior, retry guidance, opt-out flag, and the actionId confirmation flow without redundancy. Each sentence earns its place and critical operational details are front-loaded.

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?

For a tool with eight parameters, a nested registrantInfo object, no output schema, and minimal annotations, the description covers the essential gaps: the two-step confirmation mechanism, DNS initialization timing, and balance deduction. The agent has everything needed to call it and continue the workflow correctly.

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 schema already documents every parameter. The description adds useful context for initializeDnsZone ('pass initializeDnsZone:false to opt out') and implies cost behavior, but it does not add substantial meaning to most other parameters. This matches the baseline for high schema coverage.

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: 'Stage registration of a new domain name.' It clarifies this is for new registration rather than transfer or renewal and distinguishes itself by explaining the gatekeeping actionId flow, which no sibling tool description suggests.

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 clearly explains when to use the tool (new domain registration) and provides post-call guidance: present the returned actionId and call executeConfirmedAction upon approval. It stops short of explicitly contrasting with transferDomain or checkDomainAvailability, so it misses fully explicit exclusions, but the context is otherwise clear.

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