Mock sample for your project: papiNet API

The Negotiations API gives sellers the ability to proactively send discount offers to buyers who have shown an "interest" in their listings. By sending buyers discount offers on listings where they have shown an interest, sellers can increase the velocity of their sales. There are various ways for a buyer to show interest in a listing. For example, if a buyer adds the listing to their Watch list, or if they add the listing to their shopping cart and later abandon the cart, they are deemed to have shown an interest in the listing. In the offers that sellers send, they can discount their listings by either a percentage off the listing price, or they can set a new discounted price that is lower than the original listing price. For details about how seller offers work, see Sending offers to buyers.

The REST API of BeezUP system
Overview
The REST APIs provide programmatic access to read and write BeezUP data.
Basically, with this API you will be able to do everything like you were with your browser on https://go.beezup.com !
The main features are:
Register and manage your account
Create and manage and share your stores with your friends/co-workers.
Import your product catalog and schedule the auto importation
Search the channels your want to use
Configure your channels for your catalogs to export your product information:
cost and general settings
category and columns mappings
your will be able to create and manage your custom column
put in place exlusion filters based on simple conditions on your product data
override product values
get product vision for a channel catalog scope
Analyze and optimize your performance of your catalogs on all yours channels with different type of reportings by day, channel, category and by product.
Automatize your optimisation by using rules!
And of course... Manage your orders harvested from all your marketplaces:
Synchronize your orders in an uniformized way
Get the available actions and update the order status
...and more!
Authentication credentials
The public API with the base path /v2/public have been put in place to give you an entry point to our system for the user registration, login and lost password. The public API does not require any credentials.
We give you the some public list of values and public channels for our public commercial web site www.beezup.com.
The user API with the base path /v2/user requires a token which is available on this page:
https://go.beezup.com/Account/MyAccount
Things to keep in mind
API Rate Limits
The BeezUP REST API is limited to 100 calls/minute.
Media type
The default media type for requests and responses is application/json. Where noted, some operations support other content types. If no additional content type is mentioned for a specific operation, then the media type is application/json.
Required content type
The required and default encoding for the request and responses is UTF8.
Required date time format
All our date time are formatted in ISO 8601 format: 2014-06-24T16:25:00Z.
Base URL
The Base URL of the BeezUP API Order Management REST API conforms to the following template.
https://api.beezup.com
All URLs returned by the BeezUP API are relative to this base URL, and all requests to the REST API must use this base URL template.
You can test our API on https://api-docs.beezup.com/swagger-ui\\
You can contact us on gitter, #BeezUP/API

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

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.

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

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

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

Use this api to fetch information to Amazon products and more.

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

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.

API2Cart