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Text Chat

Send text messages and handle streaming responses from AI characters.

Sending Messages​

Basic Send​

// Fire-and-forget (synchronous wrapper)
character.SendText("Hello!");

// Async
await character.SendTextAsync("Hello!");

Text-Only Mode​

By default, SendText automatically suppresses TTS when no voice session is active. To explicitly control this, pass a second bool argument:

// Force text-only (no TTS audio generated)
character.SendText("Hello!", true);

// Force voice response (even without an active voice session)
character.SendText("Hello!", false);

Scripted Lines​

Use SayLine / SayLineAsync to make the character speak a specific prewritten line verbatim instead of generating a response from the LLM:

// Fire-and-forget
character.SayLine("Welcome to the museum!");

// Async, with optional text-only override
await character.SayLineAsync("Welcome to the museum!", textOnly: false);

When textOnly is false (the default), the server generates TTS audio for the line. When true, the line is delivered as text only.

Handling Streaming Responses​

Bot responses arrive as a stream of chunks. Each BotResponse event contains a piece of the full reply.

Accumulating Text​

private string _fullResponse = "";

void Start()
{
    character.OnBotResponse += HandleBotResponse;
}

void HandleBotResponse(BotResponse response)
{
    if (response.IsFinal)
    {
        // Final chunk: response.Text contains the complete response
        _fullResponse = response.Text;
        Debug.Log($"Complete: {_fullResponse}");
    }
    else
    {
        // Partial chunk: accumulate
        _fullResponse += response.Text;
    }
}

Using CurrentPartialResponse​

The EstuaryCharacter component automatically accumulates streaming text:

void Update()
{
    // Always shows the latest accumulated text
    responseLabel.text = character.CurrentPartialResponse;
}

BotResponse Fields​

FieldTypeDescription
TextstringText content of this chunk
IsFinalbooltrue when the response is complete
IsPartialbooltrue for streaming chunks
MessageIdstringUnique ID for this response
ChunkIndexintSequential index of this chunk
IsInterjectionbooltrue if this is a proactive message

Chat UI Example​

A simple TextMeshPro-based chat display:

using UnityEngine;
using TMPro;
using Estuary;
using Estuary.Models;

public class ChatUI : MonoBehaviour
{
    [SerializeField] private EstuaryCharacter character;
    [SerializeField] private TMP_InputField inputField;
    [SerializeField] private TMP_Text chatLog;
    [SerializeField] private TMP_Text streamingText;

    void Start()
    {
        character.OnBotResponse += OnBotResponse;
        character.OnConnected += OnConnected;

        inputField.onSubmit.AddListener(OnSubmit);
    }

    void OnConnected(SessionInfo session)
    {
        chatLog.text += "\n<color=#888>[Connected]</color>";
    }

    void OnSubmit(string text)
    {
        if (string.IsNullOrEmpty(text)) return;

        // Display user message
        chatLog.text += $"\n<b>You:</b> {text}";

        // Send to character
        character.SendText(text, true);

        // Clear input
        inputField.text = "";
        inputField.ActivateInputField();

        // Clear streaming display
        streamingText.text = "";
    }

    void OnBotResponse(BotResponse response)
    {
        if (response.IsFinal)
        {
            // Move final response to chat log
            chatLog.text += $"\n<b>AI:</b> {response.Text}";
            streamingText.text = "";
        }
        else
        {
            // Show streaming text
            streamingText.text = character.CurrentPartialResponse;
        }
    }
}

Actions during a response​

Character actions arrive as typed client_action events. EstuaryCharacter forwards response text unchanged to CurrentPartialResponse and OnBotResponse; action tags are not part of the current response format.

See Action System for details on handling actions.

Interjections​

Characters can send proactive messages (interjections) without user input. These have IsInterjection = true:

character.OnBotResponse += (response) =>
{
    if (response.IsInterjection)
    {
        // Character is speaking unprompted
        ShowNotification(response.Text);
    }
};

Next Steps​

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