Talk to Excel in DeepSeek Harness: create/edit spreadsheets, formulas, styles, filters, and tables by conversation; auto-verifies formulas after every edit, repairs silent errors, and validates charts.

File-diff visualization between checkpoint time nodes for DeepSeek Harness: a read-only timeline + per-file line diff over the dsh-checkpoint-rewind checkpoints storage domain, with preview-first rollback (restore workspace files from any time node, singl