Mock sample for your project: Zalando Shop API

dropX.io API provides programmatic access to the e-commerce intelligence data.

The DocuSign REST API provides you with a powerful, convenient, and simple Web services API for interacting with DocuSign.

This API is used to retrieve seller payouts and monetary transaction details related to those payouts.

Use the Fulfillment API to complete the process of packaging, addressing, handling, and shipping each order on behalf of the seller, in accordance with the payment method and timing specified at checkout.

Note: This is a (Limited Release) API available only to select developers approved by business units. Enables a seller adding an ad or item on a Partner's site to automatically create an eBay listing draft using the item details from the Partner's site.

Service for providing information to sellers about their listings being non-compliant, or at risk for becoming non-compliant, against eBay listing policies.

The Account API gives sellers the ability to configure their eBay seller accounts, including the seller's policies (the Fulfillment Policy, Payment Policy, and Return Policy), opt in and out of eBay seller programs, configure sales tax tables, and get account information. For details on the availability of the methods in this API, see Account API requirements and restrictions.

Use the Taxonomy API to discover the most appropriate eBay categories under which sellers can offer inventory items for sale, and the most likely categories under which buyers can browse or search for items to purchase. In addition, the Taxonomy API provides metadata about the required and recommended category aspects to include in listings, and also has two operations to retrieve parts compatibility information.

Documentation of the Billbee REST API to connect a Billbee account to external aplications.
Endpoint
The Billbee API endpoint base url is https://app.billbee.io/api/v1
Activation
You have to enable the API in the settings of your Billbee account. In addition you need a Billbee API Key identifying the application you develop. To get an API key, send a mail to [email protected] and send us a short note about what you are building.
Authorization & security
Because you can access private data with the Billbee API, every request has to be sent over https and must
Contain a valid API Key identifying the application/developer. It has to be sent as the HTTP header X-Billbee-Api-Key
Contain a valid user login with billbee username and api password in form of a basic auth HTTP header
Throttling
Each endpoint has a throttle of max 2 requests per second per combination of API Key and Billbee user.
When you exceed these 2 calls, the API will return a HTTP 429 status code

The Analytics API provides data and information about a seller and their eBay business. The resources and methods in this API let sellers review information on their listing performance, metrics on their customer service performance, and details on their eBay seller performance rating. The three resources in the Analytics API provide the following data and information: Customer Service Metric – Returns data on a seller's customer service performance as compared to other seller's in the same peer group. Traffic Report – Returns data that shows how buyers are engaging with a seller's listings. Seller Standards Profile – Returns data pertaining to a seller's performance rating. Sellers can use the data and information returned by the various Analytics API methods to determine where they can make improvements to increase sales and how they might improve their seller status as viewed by eBay buyers. For details on using this API, see Analyzing seller performance.

Note: This is a (Limited Release) API available only to select developers approved by business units. This API allows third-party developers to search for and retrieve details about eBay deals and events, as well as the items associated with those deals and events.