Machine-learning based document recommendation for online real-time communication system

A non-transitory computer-readable storage medium storing computer program instructions executable to perform operations, the operations comprising:

• establishing a communication session between an agent and a user, wherein the communication session is over an electrical medium;
• causing to generate an interface on a client device associated with the agent, wherein a first portion of the interface is configured to display an exchange of one or more messages between the agent and the user for a conversation or otherwise transcribe a conversation between the agent and the user;
• obtaining, at a first time, a set of utterances from a transcript of the conversation, wherein an utterance includes a sequence of words from the agent to the user or from the user to the agent during the conversation;
• accessing a database including a plurality of articles;
• generating relevance scores between the conversation and the plurality of articles, wherein a relevance score between the conversation and an article is generated by applying at least one relevance model to the set of utterances and the article;
• selecting a subset of articles having relevance scores above a threshold value or proportion;
• and
• presenting the selected subset of articles on a second portion of the interface.