LibreChat
Multi-user, multi-provider chat platform with agents and MCP already wired in.
LibreChat is what you reach for when a single-user UI is not enough: real multi-user auth, per-user usage, switching between every major provider from one interface, plus agents, MCP tools and a code interpreter. It is heavier to operate than Open WebUI and does considerably more. The provider abstraction is the point — it means a vendor price change is a config edit, not a rewrite.
Best for: Teams and departments sharing one deployment across several model providers
Deploy: Self-hostable