According to @bcherny citing @claudeai on X, Opus 4.6 with a 1 million token context window is now the default Opus model for Claude Code users on Max, Team, and Enterprise plans, while Pro and Sonnet users can opt in via /extra-usage (source: X post by @bcherny linking @claudeai announcement). As reported by Claude on X, the 1M context is generally available for Claude Opus 4.6 and Claude Sonnet 4.6, enabling end-to-end codebase reasoning, large repository refactoring, and multi-file RAG workflows within a single session. According to the X announcement, enterprises can streamline code audits, dependency upgrades, and long-form agentic coding without chunking, reducing context fragmentation and latency from repeated retrieval. For product teams, the upgrade opens opportunities to build developer copilots that index entire monorepos, run long-context test generation, and maintain architectural consistency across services. According to the same source, Pro and Sonnet users can access the 1M window through an /extra-usage opt-in, signaling a usage-based pricing path for high-context workloads.