Three sub-layers, each with its own catalog.
Arcs — the named shapes (Sparkline, Stream, Ascent, Descent…) extracted from the corpus. Blocks — the major acts inside an arc. Anti-patterns — narrative-level failure modes (no through-line, two arcs spliced, false dichotomy).
What it is
Stub: the operational definition of "narrative" as the corpus understands it. What counts as an arc, what counts as a block, what counts as a complete narrative vs a list of slides.
Anatomy
An arc visualisation — the named shape with its blocks marked. Source: concepts.arcs + storytelling://canon/story-arcs.md.
What good looks like
Stub: 3-6 anonymised decks from the corpus showing each canonical arc shape, with the blocks labelled.
Anti-patterns
Stub: "no through-line", "two arcs spliced together", "false dichotomy", "summary as climax".