What problem does it solve? It centralizes common reference documentation for Spec-Driven Development (SDD) skills so that phase skills and orchestrators share one consistent set of conventions instead of duplicating instructions. ## Core Features & Use Cases - Persistence Contract: Defines artifact storage modes (engram, openspec, hybrid, none) and read/write behavior per mode. - Naming Conventions: Documents deterministic Engram topic keys and OpenSpec directory structures for SDD artifacts. - Phase Protocol: Supplies the common boilerplate every SDD phase sub-agent must follow, including skill loading, artifact retrieval, and return envelopes. - Use Case: When an orchestrator launches an SDD phase sub-agent, the sub-agent reads these shared references to know how to recover state, persist artifacts, and report results consistently. ## Quick Start Read the relevant shared reference file such as persistence-contract.md before implementing or invoking any SDD phase skill.