practice — discretized parameter axes: named levels, never a number (owner-approved 2026-09-29)

Contracts: LadderRung 0-4, CueDistance 0-2, Presentation theory|
application; PracticeParams carries the three named levels. Doc
comments hold the three definition tables verbatim (rung names +
definitions from the ladder doctrine; cue levels; presentation
levels).

Core: LADDER_RUNGS/CUE_LEVELS/PRESENTATIONS tables in src/core/
practice.ts (definitions verbatim) — ONE source spoken by the agents'
prompts, the dialog's stepped controls, and the exam header; core
barrel re-exports practice.ts (pure domain, browser-safe).

Agents: Part I's ladder intro now 'five rungs, numbered; the request
arrives as a rung' with bullets numbered 0-4 (definitions untouched);
Part III's parameters block replaced with the named-level doctrine
(rung = exact class, no continuum; cue counts lesson examples AND
previous problems' situations; presentation dresses, never changes);
partitioner's RESPECT THE PARAMETERS replaced (low rungs = many small
assignments, high = larger; far cue makes confusables-together MORE
important; presentation does not shape the partition). renderParams
outputs the exact named-level block. Anchor/0..1 language swept dead.

Service + store: strict union validation — floats between levels,
out-of-range, wrong strings, legacy dial shapes all 400 at the API
and fail isProblemSet (legacy sets skipped from lists; no migration —
data/practice is disposable scratch, owner wipes before testing).

UI: dialog = 5-detent ladder slider + 3-detent cue slider (each shows
the level NAME + one-line definition) + Theory|Application segmented
toggle; defaults rung 2 / cue 1 / theory; Create posts the new shape.
Exam header gains the levels line ('Direct exercise · Adjacent
context · Theory').

Tests: renderParams exact-block pin; strict-validation pins (new
tests/practice-service.test.ts — bad unions 400, legacy shape 400);
store pins (legacy floats + 2.5 rung fail); render pins (detents +
names + definitions, defaults, detent-swap, toggle active segment,
levels line); every params fixture moved off floats. 1138/1138, tsc
0, lint 0, build 0.

Docs: architecture.md — discretization paragraph (compact tables,
named-level invocation, defaults, one-table source), UI mentions;
README axes sentence.

src/core/practice.ts

@@ -11,7 +11,30 @@
  * the union of the problems' chains must equal the set's chains; the
  * partitioner's submit is validated against it.
  */
-import type { GraphEdge, GraphNode, Problem, ReasoningChain } from "./contracts.ts";
+import type { CueDistance, GraphEdge, GraphNode, LadderRung, Presentation, Problem, ReasoningChain } from "./contracts.ts";
+
+/** The named levels (owner-approved 2026-09-29) — definitions verbatim
+ *  from the ladder doctrine / the contract's tables. The UI's stepped
+ *  controls, the exam header's levels line, and the agents' prompt
+ *  rendering all speak these names — never a bare number. */
+export const LADDER_RUNGS: Record<LadderRung, { name: string; definition: string }> = {
+	0: { name: "Worked example", definition: "the solution is shown; nothing is demanded. An installation object; nothing yet to recall." },
+	1: { name: "Completion", definition: "the path is shown with a gap; the learner supplies one step. What to recall is nearly announced." },
+	2: { name: "Direct exercise", definition: "one step, no hint, but the situation makes the applicable proposition unmistakable. Trains execution, not choosing." },
+	3: { name: "Composition", definition: "several steps, chained; the path is narrow but must be held and run." },
+	4: { name: "Path-finding", definition: "several steps, the path concealed, distractors present, the statement suggesting wrong methods. The competition shape." },
+};
+
+export const CUE_LEVELS: Record<CueDistance, { name: string; definition: string }> = {
+	0: { name: "Lesson context", definition: "the textbook/toy-example shape in the teaching's own framing." },
+	1: { name: "Adjacent context", definition: "a genuinely new situation built from the teaching's own world — same domain, different setup/packaging." },
+	2: { name: "Far context", definition: "as far from the typical cue as recognition allows, the edge of the recognizable band — the proposition must still genuinely apply, and the learner must be able to find it by looking." },
+};
+
+export const PRESENTATIONS: Record<Presentation, { name: string; definition: string }> = {
+	theory: { name: "Theory", definition: "the subject's own terms — symbols, formal objects, native vocabulary." },
+	application: { name: "Application", definition: "a concrete worldly affair — a case, episode, system, or story — in which the proposition's structure appears in the wild." },
+};
 
 /** The selection's follows-edges as chains: every edge into a node joins
  *  that node's (one) chain; a node with no in- AND no out-follows-edge in