Add chat UI

Add the shipped chat transcript prefab to display scrolling conversation history on screen during character interactions.

The Convai SDK for Unity includes a ready-made ChatTranscriptUI prefab that displays scrolling chat history in real time. The prefab includes its own Canvas — drag it into the scene, and it connects to ConvaiManager automatically.

Chat history and captions

ConvaiManager.ActiveManager.Transcripts (ConvaiTranscripts) exposes two independent, combinable projections of a conversation: durable chat history and live speech-aligned captions. This page adds chat history using the shipped ChatTranscriptUI prefab. Captions use a separate, sample-only script with no shipped prefab — see Chat and subtitle modes to add captions or combine both displays in the same scene.

Projection	Consumed by	Description
Chat history	ChatTranscriptUI (shipped prefab, covered on this page)	Scrolling message bubbles — separate entries for player and character turns
Captions	SubtitleTranscriptUI (reference script, no shipped prefab)	A single caption block that updates as each turn streams, then auto-hides

Add the chat UI prefab

1

Locate the prefab

In the Project window, navigate to:

Packages/Convai SDK for Unity/Prefabs/TranscriptUI/TranscriptUI_Chat.prefab

2

Drag the prefab into the scene

Drag TranscriptUI_Chat.prefab into the Hierarchy. The prefab includes its own Canvas — no separate Canvas setup is required.

The chat UI overlay appears in the Game view. The component finds ConvaiManager automatically when the scene starts — no manual wiring is needed.

The chat input field requires an EventSystem in the scene. If your scene does not already have one, add it via GameObject > UI > Event System.

If no ConvaiManager is found at startup, the Console logs: [ChatTranscriptUI] No active ConvaiManager found.. Check that ConvaiManager is in the scene.

ChatTranscriptUI Inspector fields

If you need to customize the layout, select the prefab instance and inspect the ChatTranscriptUI component.

UI References:

Field	Type	Description
scrollRect	ScrollRect	The scroll container for the message list
chatContainer	RectTransform	Parent transform where message bubbles are instantiated
characterMessagePrefab	GameObject	Template for character speech bubbles
playerMessagePrefab	GameObject	Template for player speech bubbles
chatInputField	TMP_InputField	Text field for typed input (optional)

Fade Settings:

Field	Default	Description
fadeDuration	0.5	Seconds for fade-in/out transitions

If chatContainer is not assigned, messages will not appear and the Console logs: [ChatTranscriptUI] chatContainer is not assigned - messages will not display. The bundled prefab has all references pre-wired.

Usage examples

Example 1: Full-screen chat overlay in a corporate training simulation

Scenario: A corporate onboarding experience displays a full-screen chat history so trainees can review everything the AI mentor said.

Setup:

• Drag TranscriptUI_Chat.prefab into the Hierarchy
• Leave all references at prefab defaults

Expected outcome: Each turn appears as a new bubble — player text on the right, character text on the left. The list scrolls automatically as the conversation grows.

Next steps

With the transcript UI in place, add lip sync to drive character blendshapes from audio.

Add lip sync