Knowledge lifecycle

Layer 1 of the Knowledge OS epic (#144), built on the Knowledge model (#145). It gives every note a first-class phase and a validated way to move between phases.

Lives in the pure src/architecture/knowledge/lifecycle/ (Obsidian-free, unit-tested) plus one Obsidian-facing write service and a command.

The six states

🌱 Fleeting → 📝 Literature → 💡 Permanent → 🔬 Developing → 📚 Evergreen → 🪦 Archived

• The stored value in frontmatter is always the plain ASCII token (fleeting, literature, permanent, developing, evergreen, archived). The emoji is display-only — never written.
• A note with no / empty / unrecognized state reads as fleeting (a quick capture is fleeting until promoted). Classification never rewrites a note.

Frontmatter convention (configurable, no lock-in)

Three property names are standardized, each configurable in Settings → Knowledge lifecycle and defaulting to a plain name:

Purpose	Default property	Written by #146?
Lifecycle state	state	yes — only by an explicit transition
Capture timestamp	created	no — reserved name only
Last review	last-reviewed	no — reserved; written later by #160

Uninstalling the plugin leaves every note intact and readable.

Transition state machine

stateDiagram-v2
    [*] --> Fleeting: capture / missing state → fallback
    Fleeting --> Literature: promote
    Fleeting --> Permanent: promote (direct)
    Literature --> Permanent: promote
    Permanent --> Developing: develop
    Developing --> Evergreen: consolidate
    Evergreen --> Developing: rework (back-edge)
    Fleeting --> Archived: archive
    Literature --> Archived: archive
    Permanent --> Archived: archive
    Developing --> Archived: archive
    Evergreen --> Archived: archive
    Archived --> Fleeting: revive

The relation is exposed as pure predicates canTransition(from, to) / allowedTargets(from). Everything not drawn above (skip-ahead, self→self, arbitrary demotions) is rejected.

Changing a note's state

The "Change note state" command (visible only when a markdown note is active) opens a picker of the states reachable from the note's current state and delegates to StateTransitionService, which validates the move and, on success, writes only the configured state property through the FrontmatterService → processFrontMatter facade. An invalid move performs no write. The index re-derives that single note when the metadata cache reports the change.

Capability — new: file-system write

This is the first write in the Knowledge layer. It is scoped to one property, on one user-selected note, per explicit command — never bulk, never automatic. Classification on load is read-only. created/last-reviewed are reserved names only; #146 never writes them.

Extending

The lifecycle plugs into #145 via a LifecycleStateSchema implements StateSchema, registered with KnowledgeIndex.getInstance().registerSchemas({ state }). byState / statePartition then classify every note. The maturity score over these states is #158.

State ≠ phase. A note's lifecycle state (here) is orthogonal to a step's workflow phase (#149): a note has a state (how mature it is), a step has a phase (the kind of knowledge work it performs).