Open WebUI

Open WebUI is a self-hosted, offline-capable chat UI for LLMs. Trace its conversations in Muster by installing the Langfuse Pipelines filter.

Setup

1. Launch Open WebUI

Follow the official Open WebUI install docs.

2. Start the Pipelines container

docker run -p 9099:9099 \
  --add-host=host.docker.internal:host-gateway \
  -v pipelines:/app/pipelines \
  --name pipelines --restart always \
  ghcr.io/open-webui/pipelines:main

3. Connect Pipelines as an OpenAI provider

In Open WebUI, go to Admin Panel → Settings → Connections and add an OpenAI API connection:

• URL: http://localhost:9099/
• Password: 0p3n-w3bu!

4. Install the Muster (langfuse) filter

Go to Admin Panel → Settings → Pipelines and install from this URL:

https://github.com/open-webui/pipelines/blob/main/examples/filters/langfuse_v3_filter_pipeline.py

Add your Muster API keys (public key, secret key, host).

5. Enable usage tracking

In each model's Capabilities section, check "Usage" so token counts flow through with streaming responses.

See also

• Upstream Langfuse Open WebUI docs
• LobeChat