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

readOnlyHint=true already declares the safe-read profile, so the description's job is context, and it delivers by disclosing the returned data surface (totals, checkout-question answers, buyer details) in the absence of an output schema. It stops short of stating auth requirements, failure modes for a missing/foreign order id, or region scoping behavior.

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?

Two tight sentences: the value payload is front-loaded and the endpoint mapping trails as a compact reference. No filler, nothing that could be cut without losing 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 read-only single-resource fetch with full schema coverage and no output schema, the description supplies the essential return-content summary and endpoint mapping. Only minor gaps remain: no mention of region-scoped access semantics or error behavior when the order/event pairing is invalid.

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 all three parameters including the override_location enum are already documented. The description adds only the implicit 'event plus order' pairing, which the schema already conveys, so baseline 3 applies.

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 ('Fetch') and resource ('one order of an event'), names the resolved identifiers, and enumerates what the payload contains (totals breakdown, checkout answers, buyer details). The singular 'one order' plus the required event/order ids cleanly distinguishes it from sibling list_orders, and the REST endpoint mapping removes ambiguity.

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?

Usage is only implied: it fetches a single order when you already have event_id and order_id. There is no explicit guidance on when to prefer this over list_orders, how to obtain the order id, or when override_location applies, which are the decisions an agent actually faces.

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