No product in the candidate list is libotr, the Off-the-Record Messaging library, so none of them is the named product. The closest fits for end-to-end encrypted messaging are Matrix, whose protocol is open and decentralised 9, and Matrix's messaging API 8, but neither source describes OTR itself; libotr is not named in any of them.

A question back: Did you mean the libotr library (Off-the-Record Messaging for instant chat), and do you need it for a specific platform or language?

1. 1

   Matrixmatrix.orgverified and signed

   Matrix is an open, decentralised protocol for secure communication, which is the closest candidate for encrypted messaging, though its page does not describe OTR.

   WebsiteDocsPricing

   for agents: matrix-org

2. 2

   Matrixmatrix.toverified and signed

   Matrix messaging API offers a send_message action to post a message to a room 18.

   Website

   +47 community tools built for it

   for agents: send_message · custom_api_call