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

Beyond the annotations, the description discloses the significant financial impact ('SPENDS REAL MONEY'), pricing details, immediate acceptance with background provisioning, and the redirection behavior of purchased domains. It also explains the refusal condition. This is substantial behavioral context the annotations do not provide.

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 longer than typical but every sentence carries critical information: the money warning is front-loaded, then pricing, then workflow, then validation rule. The structure is logical and scannable, with the most important warning in caps first. It is not padded.

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 that spends money and has 3 parameters, the description covers prerequisites, costs, validation rules, and post-creation polling. The only minor gap is the exact return shape, but since the description points to get_dfy_order for progress, an agent can proceed safely. Given the absence of an output schema, this is complete enough.

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?

The input schema already provides descriptions for all three parameters (100% coverage), so the baseline is 3. The description adds value by quantifying costs for domains and mailboxes, and by re-emphasizing the domain-mailbox relationship and the option to attach mailboxes to earlier order domains. While some info duplicates the schema, the cost and process details go beyond it.

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 clearly states the action ('Places a real order'), the resources (domains and mailboxes), and distinguishes itself from siblings by directing to search_dfy_domains first and get_dfy_order after. It leaves no ambiguity about what the tool does.

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 explicitly instructs to use search_dfy_domains first to confirm availability and price, and to poll get_dfy_order for progress. It also details the hard precondition (every domain must have a mailbox) and the consequence (order refused). This gives the agent concrete when-to and when-not-to guidance.

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