Opus 4.8 hits 2,200 lines in MorganBench

Opus 4.8 marks a shift from AI as a pair programmer to AI as an autonomous engineering department.

• –The 2,200-line burst utilized Claude Code's Dynamic Workflows to orchestrate hundreds of sub-agents for simultaneous building and testing.
• –MorganBench, created by CTO Morgan Linton, has emerged as the industry's premier "vibe check" for long-horizon agentic reliability.
• –Improved honesty protocols make the model 4x less likely to allow bugs to pass, a critical threshold for shipping production code without human review.
• –High token consumption (200k+ per build) is offset by the new Effort Control toggles and mid-conversation system updates that preserve prompt cache.
• –While GPT-5.5 still leads in raw prototyping speed, Anthropic's focus on "Senior Architect" planning currently dominates complex, multi-file refactors.