What problem does it solve? Keeping main specifications in sync with change proposals is tedious and error-prone when done by hand. This Skill applies delta specs (ADDED, MODIFIED, REMOVED, RENAMED requirements) from an OpenSpec change directly into the main specs with intelligent, partial merging, without archiving the change. ## Core Features & Use Cases - Intelligent Requirement Merging: Applies ADDED, MODIFIED, REMOVED, and RENAMED requirement sections from delta specs into main specs while preserving untouched content. - Store-Aware Operation: Discovers registered OpenSpec stores via openspec store list --json and targets the correct specs root rather than a hardcoded path. - Guarded Writes: Fetches artifact rules once before writing, honors caller-narrowed delta subsets, and stops on invalid instruction responses. - Use Case: After finishing a change proposal that adds a billing requirement, run the sync to update the main billing spec with the new requirement and scenarios while leaving the change active for implementation. ## Quick Start Ask the assistant to sync the delta specs from a named change into the main specs, for example: sync the specs from my add-billing change into the main specs.