Mock sample for your project: HackathonWatch API

Twitter API v2 available endpoints

API Reference — Labs v2

API for GNU Social-compatible microblogging server

Clubhouse API

Semantria applies Text and Sentiment Analysis to tweets, facebook posts, surveys, reviews or enterprise content.

Social media management for marketers and agencies

Access Forem articles, users and other resources via API.
For a real-world example of Forem in action, check out DEV.
All endpoints that don't require authentication are CORS enabled.
Dates and date times, unless otherwise specified, must be in
the RFC 3339 format.

Description of Instagram RESTful API.
Current limitations:
Instagram service does not support cross origin headers
for security reasons, therefore it is not possible to use Swagger UI and make API calls directly from browser.
Modification API requests (POST, DELETE) require additional security scopes
that are available for Apps created on or after Nov 17, 2015 and
started in Sandbox Mode.
Consider the Instagram limitations for API calls that depends on App Mode.
Warning: For Apps created on or after Nov 17, 2015 API responses
containing media objects no longer return the data field in comments and likes nodes.
Last update: 2015-11-28

This is the REST API for trashnothing.com.
To learn more about the API or to register your app for use with the API
visit the trash nothing Developer page.
NOTE: All date-time values are UTC
and are in ISO 8601 format (eg. 2019-02-03T01:23:53).

API Reference: The StatSocial API is organized around REST. Our API is designed to have predictable, resource-oriented URLs and to use HTTP response codes to indicate API errors. We use built-in HTTP features, like HTTP authentication and HTTP verbs, which can be understood by off-the-shelf HTTP clients, and we support cross-origin resource sharing to allow you to interact securely with our API from a client-side web application (remember that you should never expose your secret API key in any public website's client-side code). JSON will be returned in all responses from the API, including errors (though if you're using API bindings, we will convert the response to the appropriate language-specific object). Contact [email protected] to obtain a test API key

Medium’s unofficial API documentation using OpenAPI specification.
Official API
Official API document can also be viewed for most up to date API spec at https://github.com/Medium/medium-api-docs.
Developer Blog - Welcome to the Medium API