Qwen3-VL Gets Stuck in Repetition Loops Under GBNF Constraints

Tests reveal that Qwen3-VL-30B-A3B falls into infinite repetition loops when using GBNF grammar-constrained decoding, endlessly repeating a single valid JSON entry until the context is exhausted. This highlights the risk of generating syntactically valid but content-empty outputs.

2026-07-14 ~ 2026-07-14 · 2 related posts

• Valid JSON Can Still Mean Empty Extractions — mattjcoles · 2026-07-14
• Qwen3-VL Syntax Constraint Causes Infinite Repetition — mattjcoles · 2026-07-14