Core Concepts

Core concepts

  • One hub (~/chain-hub): Skills, rules, agents, workflows, and registry state live in one directory (default ~/chain-hub; override with chain config set chain_home or the CHAIN_HOME environment variable). Editors read from it via symlinks after chain setup.
  • Tiered bundled skills: Every install ships 14 protected operations skills under core/skills/ (for example chain-setup, hub-learn, chain-validate). They cannot be removed with chain remove. The Hub Authoring Pack (9 removable skills such as create-skill, create-workflow) installs with chain init --with-authoring or chain add into skills/ and registers under the chain_hub bucket.
  • Registry index: Public skill metadata is published in registry/index.yaml, generated from cli/core/registry.yaml and skill frontmatter. chain add <slug> and chain search use this index.
  • Skills registry: skills-registry.yaml at the hub root tracks buckets (core, chain_hub, personal, packs, community, …), GitHub pack sources, and authorship. Folders under skills/ that are not yet listed are auto-registered on chain setup, hub API load, and chain validate --fix (typically as personal or community based on provenance).
  • Agent skill loading: Editors inject skill names + descriptions each session; the assistant reads SKILL.md when the description matches your task. Skills are not auto-created during chat — install, author, or improve them explicitly.
  • Memory rules: Global preferences live under memory/identity/; per-repo context under memory/workspaces/<id>/ after chain memory init. chain memory sync writes editor-native rule files for linked adapters.
  • Continual learning: Short events queue in learnings/queue/; the hub Brain → Pipeline tab (or chain reflect) distills them — Brain requires Chain Hub Pro. Hub-wide insights become shared skill/workflow patches; project-tagged insights (repo_hint) become workspace memory rules — grouped by project in Inbox, Drafts, and For you before you approve anything.
  • Design System: Active-project tokens live in .chain/design/profile.json; hub #design-system edits and exports Tailwind/CSS snippets. Free tier covers presets and the editor; Pro adds AI/random generators and Pro presets.
  • Git sync (optional): chain sync backs up and shares your hub across machines with a private Git remote — not Dropbox/Syncthing on skills/ in parallel.