Verifiable, secure communications between a sender and a receiver on at least one shared communication channel is provided. A manicoded key encoder produces an argument of knowledge for a secret key to the at least one shared communication channel, and a manicoded message encoder provides an implication argument indicating that knowledge of the secret key enables access to message content of the manicoded message. The argument of knowledge is included in a key manifest for the secret key within a manicoded key, and the implication argument is included in a message manifest of a manicoded message. In this way, the sender may provide message content within the manicoded message, and the receiver may operate a decoder to access the message content. A verifier may use the manicoded key and the manicoded message to verify that the receiver has access to the message content.