Sendible API
REST API for managing social media clients, scheduling posts, monitoring mentions, and accessing analytics and reports across multiple social networks. The API is live at https://api.sendible.com/api/v1 and answers HTTP 401 with Basic realm="Application" on every path, but Sendible publishes no reference, no OpenAPI and no authentication documentation - the developer portal at developers.sendible.com was retired and now 301s to the marketing home page, and the help centre's API article (id 208053026) returns 404. Credentials are issued only from inside a signed-in account.