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

Annotations already establish readOnlyHint=true and destructiveHint=false, but the description adds real behavioral context beyond them: the mutation surface is entirely absent from this API, status is immutable, and refunds are taken on the POS terminal against the original payment. That prevents an agent from fruitlessly searching sibling tools for a write path, which the annotations alone would not convey.

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?

It is front-loaded correctly — contents first, then example questions, then the ID prerequisite, then the read-only constraints. Every sentence carries information, though the closing 'Say that plainly instead of hunting for another tool' is meta-instruction that overlaps with the preceding negative enumeration.

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?

There is no output schema, so the description carries the full burden of describing the return shape — and it does, field group by field group, down to card last-4, tip and change. With one fully documented parameter and no nested objects, nothing an agent needs to call this correctly 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 description coverage is 100% and there is a single required parameter, so the baseline is 3. The description's note that the ID comes from get_orders and is not a receipt number largely restates the schema's own property description, adding emphasis rather than new syntax or format detail.

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 names a specific verb and resource and then enumerates the exact payload of a single order — line items, tax, totals, payments, refunds, customer, outlet, employee. It is unmistakably distinct from hub_get_orders (list) and hub_get_refunds (refund-only) without opening any 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?

It gives explicit entry conditions ('Takes the order ID from get_orders — a receipt number will NOT work, search for it with get_orders first') and names the alternative when the caller has a receipt. It also states what NOT to attempt (no status change, no cancel/complete, no refund creation) and where refunds actually happen, so the agent is routed away from dead ends.

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