register_domain

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

Annotations already flag destructive and idempotent behavior, but the description adds critical non-obvious details: it charges the billing method, is irreversible, requires explicit user consent, and runs asynchronously with a ~90s wait. This goes well beyond the structured annotations.

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, all essential: the billing action and irreversibility are front-loaded, followed by prerequisites and async behavior. No redundant or filler content; every sentence adds decision-relevant information.

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 destructive, side-effect-heavy tool with 7 parameters and no output schema, the description covers the critical risks, prerequisites, and execution behavior. It does not describe the response shape, but the async acceptance model is disclosed, which is the most important contextual gap.

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 each parameter thoroughly. The description adds some useful context around the quote flow and price locking, but does not need to compensate for missing schema metadata. Baseline 3 is appropriate.

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 action ('Register a domain') with a clear resource and prerequisite source ('using a quote from get_registration_quote'). It also clearly distinguishes this from related sibling tools by highlighting that it charges the account, is irreversible, and is the execution step after quoting.

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 gives explicit usage conditions: only after explicit user confirmation, requires a payment method and registrant contact, and should follow get_registration_quote. It does not name sibling alternatives explicitly, but the context makes the decision boundary clear for an agent.

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