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Decoder-only transformer

As explained in Effective Conversational AI

A decoder-only architecture is a language-model architecture trained to predict successive tokens and generate text from preceding context.

A decoder-only transformer generates text by predicting the next token from the preceding context. Unlike a classifier limited to predefined intents, it can produce specific, personalized responses and can be instructed to perform tasks such as classification, question answering, and summarization. section 4.1.4

From intent labels to useful responses

A traditional model might map a user message to one predefined intent. A decoder-only model instead continues the input with a likely text completion, allowing a conversational system to address the request directly and with context. section 4.1.4

Figure 4.4 Traditional classification models use supervised learning to predict one of several predefined classifications. They look for the intent, or meaning, of a user input. Generative models use decoding transformers to create a text completion. They predict the next sequence of tokens (loosely, words or characters) that are most likely to occur after the user input.
figure

Compare supervised classification, which selects among predefined categories, with generative decoding, which predicts the next sequence of tokens. section 4.1.4

How Effective Conversational AI covers it

How deep it goes
Defines next-token prediction, training style, and task range, but does not descend into transformer internals.
Examples
Uses conversational responses, classification, question answering, summarization, and next-token text completion as examples.
What it assumes
Requires understanding the user domain and likely problem range, while treating next-token generation as the core model behavior.
What you can do after
Evaluate whether generative modeling fits conversational tasks requiring responses beyond predefined intent categories.
How it connects
Contrasts with encoder-only and encoder–decoder architectures, traditional classification models, and prompt engineering.

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This explainer was generated by Manning's knowledge graph from the text of Effective Conversational AI. The section links point to the parts of the book it draws on.