Mock sample for your project: Just Eat UK API

The Catalog API allows users to search for and locate an eBay catalog product that is a direct match for the product that they wish to sell. Listing against an eBay catalog product helps insure that all listings (based off of that catalog product) have complete and accurate information. In addition to helping to create high-quality listings, another benefit to the seller of using catalog information to create listings is that much of the details of the listing will be prefilled, including the listing title, the listing description, the item specifics, and a stock image for the product (if available). Sellers will not have to enter item specifics themselves, and the overall listing process is a lot faster and easier.

Endpoint Structure
All URLs are in the format:
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Jumpseller API wrapper provides a public Ruby abstraction over our API;
Apps Page showcases external integrations with Jumpseller done by technical experts;
Imgbb API provides an easy way to upload and temporaly host for images and files.

Note: This is a (Limited Release) API available only to select developers approved by business units. The Feed API provides the ability to download TSV_GZIP feed files containing eBay items and an hourly snapshot file of the items that have changed within an hour for a specific category, date and marketplace. In addition to the API, there is an open source Feed SDK written in Java that downloads, combines files into a single file when needed, and unzips the entire feed file. It also lets you specify field filters to curate the items in the file.

One API serving data spanned across multiple verticals

This API allows 3rd party developers to translate item title, description, search query.

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.

papinet API is a global initiative for the Forst and Paper supply chain.

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

Please make sure you use the correct version of the APIs for your use case. To find out the appropriate version, go to the API Docs drop down on the menu.

The Metadata API has operations that retrieve configuration details pertaining to the different eBay marketplaces. In addition to marketplace information, the API also has operations that get information that helps sellers list items on eBay.

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