r/OpenWebUI

Next milestone: v0.7.0 - Lock in; accelerate and improve Open WebUI!

I wanted to share my OpenAlex MCP Server that I created for using scientific research within OpenWebUI. OpenAlex is a free scientific search index with over 250M indexed works.

I created this service since all the existing MCP servers or tools didn't really satisfy my needs, as they did not enable to filter for date or number of citations. The server can easily be integrated into OpenWebUI with MCPO or with the new MCP integration (just set Authentication to None in the OpenWebUI settings). Happy to provide any additional info and glad if it's useful for someone else:

Example Query:

search_openalex(
    "neural networks", 
    max_results=15,
    from_publication_date="2020-01-01",
    is_oa=True,
    cited_by_count=">100",
    institution_country="us"
)

Among the most notable:

• MCP support (streamable http)

• OAuth 2.1 for tools

• Redesigned external tool UI

• External & Built-In Tools can now support rich UI element embedding, allowing tools to return HTML content and interactive iframes that display directly within chat conversations with configurable security settings (think of generating flashcards, canvas, and so forth)

• Perplexity websearch and Ollama Websearch now supported

• Attach Webpage button was added to the message input menu, providing a user-friendly modal interface for attaching web content and YouTube videos

• Many performance enhancements

• A boatload of redesigns, and EVEN more features and improvements

• Another boatload of fixes

You should definitely check out the full list of changes, it's very comprehensive and impressive:

Docs were also merged just now; docs live now on

Hi everyone,

I’m running Open WebUI inside a Docker container on an Azure VM, and the disk is almost full.
After analyzing the filesystem, I found that the main space usage comes from Docker data and Open WebUI’s cache:

$ sudo du -h --max-depth=1 /var/lib/docker | sort -hr
55G  /var/lib/docker
33G  /var/lib/docker/overlay2
12G  /var/lib/docker/containers
11G  /var/lib/docker/volumes

Inside volumes/open-webui/_data, I found:

9.3G  /var/lib/docker/volumes/open-webui/_data
6.1G  /var/lib/docker/volumes/open-webui/_data/cache
5.9G  /var/lib/docker/volumes/open-webui/_data/cache/embedding/models
3.1G  /var/lib/docker/volumes/open-webui/_data/vector_db

So most of the space is taken by:

• cache/embedding/models → 5.9 GB

• overlay2 → 33 GB

• containers → 12 GB

• vector_db → 3.1 GB

I’ve already verified that:

• No stopped containers (docker ps -a clean)

• No dangling images (docker images -f "dangling=true")

• Container logs are removed (no *-json.log files)

• Backup snapshots are normal

🧠 Questions:

1. Is it safe to delete /cache/embedding/models (does Open WebUI recreate these automatically)?

2. Is there a proper way to reduce the size of overlay2 without breaking active containers?

3. Has anyone else faced the same issue where Open WebUI cache grows too large on Docker setups?

The VM is 61 GB total, 57 GB used (93%).
I’m trying to find the safest way to free space without breaking embeddings or the vector database.

Thanks in advance 🙏