- Verification loops significantly improve coding agents' ability to complete multi-step web development tasks by catching bugs early.
- Using IronBee (a verification layer) with DeepSeek (low-cost model) increased task completion from an average of 6.8 to 17 out of 20 tasks, matching the performance of Claude Opus (frontier model).
- DeepSeek with IronBee achieved similar results to Opus alone but at about 1/7th the cost ($2.4 vs. $15 per run), showing verification can reduce reliance on expensive models.
- The study emphasizes that verification helps most with bugs that only appear when the running application is tested, especially in sequential tasks where early errors compound.
- Limitations include using only one project and model pair initially, with plans to expand testing to more models, projects, and a cost-matched ablation study for broader insights.