Common issues with Question and Answer Chain in Duaer

No prompt specified

With Source for Prompt (User Message) set to Connected Chat Trigger Node, the node looks for a chatInput field. Without it you get this error: rename the field to chatInput with Edit Fields (Set), or switch to Define below.

With Define below, the error means Prompt (User Message) is empty or its expression did not resolve. Check that the referenced fields exist and are not null.

A Retriever sub-node must be connected and enabled

The Question and Answer Chain has no retriever, or the retriever is deactivated. Select + on the Retriever input under the node, pick a retriever such as Vector Store Retriever, and connect a vector store to it. The Model input works the same way: without a model you get A Model sub-node must be connected and enabled.

Answers are too short

• Raise the output limit on the model sub-node, such as Options > Maximum Number of Tokens on OpenAI Chat Model.
• Switch to a model with a larger context window and more detailed output.
• Ask for fuller answers in Options > System Prompt Template, keeping the {context} placeholder.
• Split a large question into steps, answer each with an AI node, then combine the answers.