Configuration Overview

Chat UI is configured through environment variables. Default values are in .env; override them in .env.local or via your environment.

Required Configuration

Chat UI connects to any OpenAI-compatible API endpoint:

OPENAI_BASE_URL=/static-proxy?url=https%3A%2F%2Frouter.huggingface.co%2Fv1
OPENAI_API_KEY=hf_************************

Models are automatically discovered from ${OPENAI_BASE_URL}/models. No manual model configuration is required.

Database

MONGODB_URL=mongodb://localhost:27017
MONGODB_DB_NAME=chat-ui

For development, MONGODB_URL is optional - Chat UI falls back to an embedded MongoDB that persists to ./db.

Model Overrides

To customize model behavior, use the MODELS environment variable (JSON5 format):

MODELS=`[
  {
    "id": "meta-llama/Llama-3.3-70B-Instruct",
    "name": "Llama 3.3 70B",
    "multimodal": false,
    "supportsTools": true
  }
]`

Override properties:

• id - Model identifier (must match an ID from the /models endpoint)
• name - Display name in the UI
• multimodal - Enable image uploads
• supportsTools - Enable MCP tool calling for models that don’t advertise tool support
• parameters - Override default parameters (temperature, max_tokens, etc.)

Task Model

Set a specific model for internal tasks (title generation, etc.):

TASK_MODEL=meta-llama/Llama-3.1-8B-Instruct

If not set, the current conversation model is used.

Voice Transcription

Enable voice input with Whisper:

TRANSCRIPTION_MODEL=openai/whisper-large-v3-turbo
TRANSCRIPTION_BASE_URL=/static-proxy?url=https%3A%2F%2Frouter.huggingface.co%2Fhf-inference%2Fmodels%3C!-- HTML_TAG_END -->

Feature Flags

LLM_SUMMARIZATION=true          # Enable automatic conversation title generation
ENABLE_DATA_EXPORT=true         # Allow users to export their data
ALLOW_IFRAME=false              # Disallow embedding in iframes (set to true to allow)

User Authentication

Use OpenID Connect for authentication:

OPENID_CLIENT_ID=your_client_id
OPENID_CLIENT_SECRET=your_client_secret
OPENID_SCOPES="openid profile"

See OpenID configuration for details.

Environment Variable Reference

See the .env file for the complete list of available options.