name = "Grok 4.1 Fast (Reasoning)" description = "Fast Grok model for responsive chat, reasoning, and tool-assisted work" family = "grok" release_date = "2025-08-28" last_updated = "2025-08-28" attachment = false reasoning = true reasoning_options = [] temperature = true knowledge = "2023-10" tool_call = true open_weights = false [cost] input = 0.2 output = 1.5 cache_read = 0.02 [limit] context = 256_000 output = 128_000 [modalities] input = ["text"] output = ["text"]