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

Annotations already declare readOnlyHint and openWorldHint, so the description adds real value beyond them: the cost model ('Free to call'), the supported TLD restriction (.com/.org only), and the derivation behavior from a brand name. It does not describe pagination or suggestion ordering, but for a read-only search that is a minor gap.

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 with zero filler, leading with what it does, then limits, then the call-to-action routing to create_dfy_order. Every sentence carries a distinct piece of 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?

With no output schema, the description still conveys the return content (availability and pricing) and the key constraint (.com/.org), which is enough for an agent to call and interpret it. It could say more about result shape or suggestion count, but nothing critical for correct invocation is missing.

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 the schema already documents query, tlds, and limit in detail. The description only reinforces the brand-name input and the com/org constraint, adding no syntax or format detail beyond the schema, which is the expected baseline when the schema does the heavy lifting.

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 (checks availability and pricing) plus resource (sending domains derived from a brand name) and gives a concrete derivation example ('acme' -> acme-mail.com). An agent can distinguish it from create_dfy_order and other domain/order tools without opening a schema.

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?

Explicitly says when to use it ('use it to pick domains and see exact prices before create_dfy_order') and names the sibling that follows it, plus notes it is free to call so there is no cost risk in exploring. Nothing about invocation timing is left to inference.

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