Four experiments on PayPal API integration and migration tasks, measuring what happens when AI coding agents get API knowledge through Context Plugins vs relying on web search.
Same task, same IDE, same model — run twice. Once with the agent using only web search, once with Context Plugins providing live API source, models, and controllers.
Mature open-source e-commerce platform. Plugin architecture, decade of production use, strict backward-compatibility expectations.
Reference architecture from the .NET team. Services-based design, .NET Aspire orchestration, clean separation of concerns.
Average code quality scores across all 4 experiments, rated 1–5.
Replace hand-rolled HttpClient calls with the official SDK without breaking OAuth, order creation, capture, refund, or void flows.
OAuthAuthorizationController didn't exist in the SDKList<T> became List:With the existing PayPal plugin removed, integrate PayPal as a payment method where the buyer approves first, and then the payment is captured on order confirmation.
ask, endpoint_search, model_search throughoutMigrate a direct HTTP implementation to the official PayPal Server SDK in a modern .NET 9 service-based application.
/integrate_api tool from the first promptask, endpoint_search, model_search proactivelyAdd a two-part payment flow — buyer approves at checkout, payment captured after stock confirmation — with no prior PayPal integration.
?paid=1 query param triggers false approvalsintegrate_api, ask, model_search, endpoint_searchBrowse APIs with live Context Plugins and see what authoritative API context looks like for your stack.
Browse API Showcase