Anthropic's June 2026 launch of Claude Fable 5 as its first publicly available Mythos-class model, followed by the September 5.1 update, set the output token price at $50 per million tokens—the highest among its current lineup—reflecting its positioning for demanding long-horizon coding, agentic workflows, and 1M-token context tasks. This premium rate has held steady through October amid improved prompt caching and batch discounts, while competitors like Opus 5.5 sit at $20 output. Traders are watching for any late-year adjustments ahead of potential 2027 model cycles or competitive pressure from lower-cost frontier alternatives, though no official price changes have been signaled.