text-generation-webui/docs/Extensions.md

This web UI supports extensions. They are simply files under

extensions/your_extension_name/script.py

which can be invoked with the

--extension your_extension_name

command-line flag.

text-generation-webui-extensions

The link above contains a directory of user extensions for text-generation-webui.

If you create an extension, you are welcome to host it in a GitHub repository and submit it to the list above.

Built-in extensions

Most of these have been created by the extremely talented contributors that you can find here: contributors.

Extension	Description
api	Creates an API with two endpoints, one for streaming at /api/v1/stream port 5005 and another for blocking at /api/v1/generate por 5000. This is the main API for this web UI.
google_translate	Automatically translates inputs and outputs using Google Translate.
character_bias	Just a very simple example that biases the bot's responses in chat mode.
gallery	Creates a gallery with the chat characters and their pictures.
silero_tts	Text-to-speech extension using Silero. When used in chat mode, it replaces the responses with an audio widget.
elevenlabs_tts	Text-to-speech extension using the ElevenLabs API. You need an API key to use it.
send_pictures	Creates an image upload field that can be used to send images to the bot in chat mode. Captions are automatically generated using BLIP.
whisper_stt	Allows you to enter your inputs in chat mode using your microphone.
sd_api_pictures	Allows you to request pictures from the bot in chat mode, which will be generated using the AUTOMATIC1111 Stable Diffusion API. See examples here.
llava	Adds LLaVA multimodal model support. For detailed description see README.md in the extension directory.
openai	Creates an API that mimics the OpenAI API and can be used as a drop-in replacement.

How to write an extension

script.py has access to all variables in the UI through the modules.shared module, and it may define the following functions:

Function	Description
def ui()	Creates custom gradio elements when the UI is launched.
def input_modifier(string)	Modifies the input string before it enters the model. In chat mode, it is applied to the user message. Otherwise, it is applied to the entire prompt.
def output_modifier(string)	Modifies the output string before it is presented in the UI. In chat mode, it is applied to the bot's reply. Otherwise, it is applied to the entire output.
def bot_prefix_modifier(string)	Applied in chat mode to the prefix for the bot's reply (more on that below).
def custom_generate_chat_prompt(...)	Overrides the prompt generator in chat mode.
def tokenizer_modifier(state, prompt, input_ids, input_embeds)	Modifies the input_ids/input_embeds fed to the model. Should return prompt, input_ids, input_embeds. See llava extension for an example

Additionally, the script may define two special global variables:

params dictionary

params = {
    "language string": "ja",
}

This dicionary can be used to make the extension parameters customizable by adding entries to a settings.json file like this:

"google_translate-language string": "fr",

input_hijack dictionary

input_hijack = {
    'state': False,
    'value': ["", ""]
}

This is only relevant in chat mode. If your extension sets input_hijack['state'] to True at any moment, the next call to modules.chat.chatbot_wrapper will use the values inside input_hijack['value'] as the user input for text generation. See the send_pictures extension above for an example.

Additionally, your extension can set the value to be a callback, in the form of def cb(text: str, visible_text: str) -> [str, str]. See the llava extension above for an example.

The bot_prefix_modifier

In chat mode, this function modifies the prefix for a new bot message. For instance, if your bot is named Marie Antoinette, the default prefix for a new message will be

Marie Antoinette:

Using bot_prefix_modifier, you can change it to:

Marie Antoinette: *I am very enthusiastic*

Marie Antoinette will become very enthusiastic in all her messages.

Using multiple extensions at the same time

In order to use your extension, you must start the web UI with the --extensions flag followed by the name of your extension (the folder under text-generation-webui/extension where script.py resides).

You can activate more than one extension at a time by providing their names separated by spaces. The input, output and bot prefix modifiers will be applied in the specified order. For custom_generate_chat_prompt, only the first declaration encountered will be used and the rest will be ignored.

python server.py --extensions enthusiasm translate # First apply enthusiasm, then translate
python server.py --extensions translate enthusiasm # First apply translate, then enthusiasm

custom_generate_chat_prompt example

Below is an extension that just reproduces the default prompt generator in modules/chat.py. You can modify it freely to come up with your own prompts in chat mode.

def custom_generate_chat_prompt(user_input, state, **kwargs):
    impersonate = kwargs['impersonate'] if 'impersonate' in kwargs else False
    _continue = kwargs['_continue'] if '_continue' in kwargs else False
    also_return_rows = kwargs['also_return_rows'] if 'also_return_rows' in kwargs else False
    is_instruct = state['mode'] == 'instruct'
    rows = [f"{state['context'].strip()}\n"]

    # Finding the maximum prompt size
    chat_prompt_size = state['chat_prompt_size']
    if shared.soft_prompt:
        chat_prompt_size -= shared.soft_prompt_tensor.shape[1]
    max_length = min(get_max_prompt_length(state), chat_prompt_size)

    if is_instruct:
        prefix1 = f"{state['name1']}\n"
        prefix2 = f"{state['name2']}\n"
    else:
        prefix1 = f"{state['name1']}: "
        prefix2 = f"{state['name2']}: "

    i = len(shared.history['internal']) - 1
    while i >= 0 and len(encode(''.join(rows))[0]) < max_length:
        if _continue and i == len(shared.history['internal']) - 1:
            rows.insert(1, f"{prefix2}{shared.history['internal'][i][1]}")
        else:
            rows.insert(1, f"{prefix2}{shared.history['internal'][i][1].strip()}{state['end_of_turn']}\n")
        string = shared.history['internal'][i][0]
        if string not in ['', '<|BEGIN-VISIBLE-CHAT|>']:
            rows.insert(1, f"{prefix1}{string.strip()}{state['end_of_turn']}\n")
        i -= 1

    if impersonate:
        rows.append(f"{prefix1.strip() if not is_instruct else prefix1}")
        limit = 2
    elif _continue:
        limit = 3
    else:
        # Adding the user message
        user_input = fix_newlines(user_input)
        if len(user_input) > 0:
            rows.append(f"{prefix1}{user_input}{state['end_of_turn']}\n")

        # Adding the Character prefix
        rows.append(apply_extensions(f"{prefix2.strip() if not is_instruct else prefix2}", "bot_prefix"))
        limit = 3

    while len(rows) > limit and len(encode(''.join(rows))[0]) >= max_length:
        rows.pop(1)
    prompt = ''.join(rows)

    if also_return_rows:
        return prompt, rows
    else:
        return prompt