ToolLoop: Closed-Loop Tool-Use Data Synthesis via Decomposed Generation and Dynamic Self-Feedback
This is the missing piece for tool-use reliability. A 4B model trained on 11K generated examples reaches 86% accuracy on the Berkeley Function Calling Leaderboard, and crucially, it generalizes to functions outside the training set. If you're training agents on Claude or another model, this data synthesis pattern beats static filtering. The shift from generate-then-filter to generate-verify-refine is the real contribution, not the 11K examples.