GPT-5.6 Luna vs Grok 4.20 Multi-Agent

OpenAI GPT-5.6 LunaxAI Grok 4.20 Multi-Agent
VendorOpenAIxAI
Context window1,050,0002,048,000
Max output128,0001,000,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2026-07-092026-03-09