Drex has open weights but uses the Open RAIL-M license with usage restrictions, so it is not open source as defined by OSI; it offers both hosted and self-hosted channels; it is based on Qwen3.6-35B-A3B MoE, with 35B total parameters and about 3B activated; self-hosted default context is 16K with a maximum of 128K, and hosted is 128K.