Lexuan Zhang

Author directory

2026

Handwritten text by language learners couples recognition errors with grammatical errors, which makes automatic correction of such text harder than either subproblem alone. Visual Chinese grammatical error correction asks a system to read a handwritten sentence image and to emit both a fully corrected sentence and a list of localized visual edits. We describe a training-free pipeline that makes one call to a vision–language model (VLM) per image and jointly requests a verbatim transcription, a minimal-edit correction, and a typed bounding-box edit list in a single JSON object; a deterministic packer enforces schema and coverage, and a second engine fills only the test images for which the first produces no valid record. A paired 19-image development comparison under a proxy of the official F0.5 metric finds that two VLMs obtain the same edit true-positive count while one emits nearly twice as many edits; the more conservative engine has higher edit precision on this slice. The system obtains an official score of 0.5905 on the hidden sentence-level test set of the VisCGEC-v2.0 shared task. The result suggests that a single-pass training-free VLM pipeline is viable for this task, and that edit precision is a useful engine-selection signal on the measured development slice.