Open-source spec CLI: the spec, tasks and proof of done live in git, so any AI coding agent (Claude Code, Codex, Cursor, Copilot) can pick up where another stopped. Powers SpecWithCode: specwithcode.com
OpenSpec Plus — Agentic skills that enhance OpenSpec's Spec-Driven Development through better discovery, requirements, design decisions, execution planning and execution. Works with Claude Code, OpenCode, Github Copilot and any other AI coding agents