Coding agents crossed from error-prone demos to daily tools
Claude Opus 4.5 and GPT-5.1 turned coding agents from tools that “often make mistakes” into systems reliable enough for day-to-day use, changing what individual developers can realistically attempt. Willison’s chronological keynote traces that shift from the November 2025 releases through 2026, showing the practical change as a pairing: a stronger model inside a coding-agent harness, rather than a model upgrade alone.