Fix wave chunk A: no Default option, composer = strong slot, catalog revalidation

Item 1 — no Default in the slot selectors (owner, fix wave): a
"default" model is not a thing in this app. Picking Default used to
delete the slot and re-arm the first-run gate — incoherent. Now the
model menus carry NO clear row at all (a slot holds a pick or reads
"—"), the thinking menus carry a "—" row (menu-none) that clears only
the thinking pin, and the hint line is the roster only — the resolved
factory pin is never named. Master's amendment confirmed: the
factory-pin hint is SUPERSEDED entirely (Platform removes the pins).

Item 2 — the composer control IS the strong slot (owner: "one and the
same"): ModelControl (model-picker.tsx) reads the raw models section
(GET /api/settings) and the federated catalog, and writes
PUT /api/settings/models via composeSlotModel — the same seam the
settings Agent section and SetupDialog use. Props retired: chatId,
settings, onSaved, fallbackModelId, noDefaultModel — the control is
self-sufficient and identical on every surface (composer, home dock,
/chat/new). The per-chat model PUT is gone from the UI; legacy
per-chat overrides keep resolving server-side. StatsBar/DockOverlay
plumbing slimmed accordingly; chat.tsx drops its per-chat settings
state and initialSettings prop.

Item 3 — the composer catalog cache no longer freezes per page load:
fetchCatalog(force) invalidates, and every model-menu open revalidates
in the background (stale-while-revalidate — cached list shows
instantly, the fresh federation swaps in). Owner's repro verified live:
a key saved mid-session widens the menu without a reload.

Item 4 — stale doc comments fixed: model-catalog.ts's "OpenRouter
catalog"/"multi-provider future" (Platform's file — mechanical,
flagged for review) and model-picker's retired "config-pinned"/
per-chat-PUT narrative.

Live-verified on 3001: unpicked slots read "—" everywhere; model
menus have no clear row; the "—" thinking row clears the pin but
keeps the model; composer pick writes strong and preserves cheap/
vision siblings; thinking pill writes strong.thinkingLevel; groq key
added mid-session appears in the open menu without reload. Caught in
live verification: the record fetch was mapping the WHOLE settings
record into the models section (picks never wrote) — fixed to read
body.settings.models.

Gates: typecheck, lint, 807/807, build.

app/chat/[id]/page.tsx

@@ -25,7 +25,6 @@ export default async function ChatPage({
 			// A teacher turn that outlived its client: the remounted view must
 			// attach (busy shimmer + poll), never resurrect the stale record.
 			initiallyInFlight={isTurnRunning(chat.id)}
-			initialSettings={chat.settings}
 		/>
 	);
 }

components/chat.tsx

@@ -118,7 +118,6 @@ export function Chat({
 	initialMessages,
 	initialPrompt,
 	initiallyInFlight,
-	initialSettings,
 }: {
 	chatId: string;
 	title: string;
@@ -127,8 +126,6 @@ export function Chat({
 	/** A teacher turn is running server-side but attached to no client
 	 * (navigated away mid-turn, returned while in flight). */
 	initiallyInFlight?: boolean;
-	/** The record's per-chat model/thinking settings (the picker's seed). */
-	initialSettings?: ChatSettings;
 }) {
 	const { messages, sendMessage, addToolOutput, setMessages, status, error, stop } =
 		useChat<TeacherUIMessage>({
@@ -445,7 +442,6 @@ export function Chat({
 	const [turns, setTurns] = useState<TurnUsage[]>([]);
 	// The per-chat model control state (model-picker writes via PUT; the
 	// record is the source of truth, lifted here so the stats bar re-renders).
-	const [settings, setSettings] = useState<ChatSettings | undefined>(initialSettings);
 	// The dock's reserved tail height (DockOverlay reports it; the spacer at
 	// the end of the transcript renders it). Lives here because the spacer is
 	// inside the scroller while the dock overlays OUTSIDE it — two parents.
@@ -963,8 +959,6 @@ export function Chat({
 				<DockOverlay
 					pending={pending}
 					chatId={chatId}
-					settings={settings}
-					onSettingsSaved={setSettings}
 					plan={<PlanMarginalia messages={messages} />}
 					onOpenPlan={() => setPlanOpen(true)}
 					requiresReveal={requiresReveal}
@@ -1054,8 +1048,6 @@ function DockOverlay({
 	composer,
 	onSubmitAnswer,
 	chatId,
-	settings,
-	onSettingsSaved,
 	onReserve,
 	plan,
 	onOpenPlan,
@@ -1073,8 +1065,6 @@ function DockOverlay({
 	onSubmitAnswer: (output: QuestionAnswerData) => void;
 	/** The model control's pass-through (the stats bar hosts it). */
 	chatId: string;
-	settings?: ChatSettings;
-	onSettingsSaved: (settings: ChatSettings) => void;
 	/** Reports the dock's settled height (block + gradient) — ChatView's
 	 *  dockReserve state feeds the transcript's spacer from it. */
 	onReserve: (h: number) => void;
@@ -1351,9 +1341,6 @@ function DockOverlay({
 					    morphing shell so it never joins a height animation. */}
 					<StatsBar
 						turns={turns}
-						chatId={chatId}
-						settings={settings}
-						onSettingsSaved={onSettingsSaved}
 						dictationSlot={dictationSlot}
 					/>
 				</div>

components/home.tsx

@@ -167,15 +167,11 @@ export function Home({ initialSettings, initialConfigured }: { initialSettings:
 					</form>
 					{/* Same as the chat view's under-composer stats bar (owner) — no
 					    session yet, so the free LEFT side carries the knowledge-context
-					    budget (session-data slot), while the RIGHT keeps the model +
-					    thinking control (deferred save). */}
+					    budget (session-data slot), while the RIGHT keeps the strong-
+					    slot control (fix wave: the pills write /api/settings/models). */}
 					<StatsBar
 						dictationSlot={<DictationBar dictation={dictation} />}
 						turns={[] as TurnUsage[]}
-						chatId=""
-						noDefaultModel
-						settings={settings}
-						onSettingsSaved={saveDraft}
 						leftSlot={
 							<GraphContextControl
 								value={effectiveContextTokens(settings)}

components/model-picker.tsx

@@ -1,32 +1,25 @@
 "use client";
 
-/**
- * The model + thinking control (model-control wave, 2026-09-12) — the stats
- * bar's right side. ONE controller for the conversation agents (prober +
- * teacher are functionally one agent); background sub-agents stay
- * config-pinned. Writes go to PUT /api/chats/[id]/settings (validated
- * server-side against pi-ai's catalog) and take effect on the next turn by
- * construction — the agents are stateless per turn.
- *
- * The data is pi-ai's catalog (GET /api/models): the model menu is a fuzzy
- * search over "provider id name" (core/fuzzy.ts — pi's /model pattern), and
- * the thinking menu lists EXACTLY the chosen model's supported levels
- * (getSupportedThinkingLevels — GLM-5.3-flash shows low|high|max, never a
- * level it would silently clamp). Menus open ABOVE the buttons (the
- * composer owns everything below).
- */
-
 import { useCallback, useEffect, useRef, useState } from "react";
-import type { ChatSettings, ModelCatalogEntry, ModelCatalogResponse } from "@/src/core";
+import type { ModelCatalogEntry, ModelCatalogResponse, ModelsSettings } from "@/src/core";
+import type { ThinkingLevel } from "@earendil-works/pi-agent-core";
 import { prettyModel } from "@/components/usage-format";
 import { ModelMenuList, ThinkingMenuList } from "@/components/settings/model-menu";
+import { composeSlotModel } from "@/components/settings/agent-section";
 
-/** GET /api/models is fetched once per page load and shared by every
- *  picker instance (the catalog is static within a pi-ai version). */
+/** GET /api/models is cached per page load for instant menu opens, but
+ *  the federation is LIVE per call — keys saved mid-session widen the
+ *  catalog immediately server-side. ModelControl therefore re-fetches on
+ *  every model-menu open (stale-while-revalidate: the cached list shows
+ *  instantly, the fresh one swaps in while the menu is open). */
 let catalogCache: ModelCatalogResponse | undefined;
 let catalogInflight: Promise<ModelCatalogResponse> | undefined;
 
-function fetchCatalog(): Promise<ModelCatalogResponse> {
+function fetchCatalog(force = false): Promise<ModelCatalogResponse> {
+	if (force) {
+		catalogCache = undefined;
+		catalogInflight = undefined;
+	}
 	catalogInflight ??= fetch("/api/models")
 		.then((r) => {
 			if (!r.ok) throw new Error(`catalog request failed: ${r.status}`);
@@ -37,13 +30,13 @@ function fetchCatalog(): Promise<ModelCatalogResponse> {
 			return c;
 		})
 		.catch((err) => {
-			catalogInflight = undefined; // retry on next mount
+			catalogInflight = undefined; // retry on next mount/open
 			throw err;
 		});
 	return catalogInflight;
 }
 
-function useModelCatalog(): ModelCatalogResponse | undefined {
+function useModelCatalog(): { catalog: ModelCatalogResponse | undefined; refresh: () => void } {
 	const [catalog, setCatalog] = useState(catalogCache);
 	useEffect(() => {
 		if (catalogCache) return;
@@ -51,14 +44,21 @@ function useModelCatalog(): ModelCatalogResponse | undefined {
 		fetchCatalog()
 			.then((c) => alive && setCatalog(c))
 			.catch(() => {
-				/* the picker stays closed on failure; the buttons still display
-				   the effective model from props */
+				/* the picker stays closed on failure; the buttons still
+				   display the strong slot from the record fetch */
 			});
 		return () => {
 			alive = false;
 		};
 	}, []);
-	return catalog;
+	const refresh = useCallback(() => {
+		fetchCatalog(true)
+			.then(setCatalog)
+			.catch(() => {
+				/* refresh is best-effort: the cached list stays on failure */
+			});
+	}, []);
+	return { catalog, refresh };
 }
 
 const LEVEL_LABEL: Record<string, string> = {
@@ -71,43 +71,51 @@ const LEVEL_LABEL: Record<string, string> = {
 	max: "Max",
 };
 
-
-export function ModelControl({
-	chatId,
-	settings,
-	onSaved,
-	fallbackModelId,
-	noDefaultModel,
-}: {
-	chatId: string;
-	/** The record's current settings (undefined = config pin). */
-	settings?: ChatSettings;
-	/** Lifts the persisted settings into the chat view's state. */
-	onSaved: (settings: ChatSettings) => void;
-	/** The last turn's actual model (from the turns log) — the label until
-	 *  the catalog (with config's defaults) finishes loading. */
-	fallbackModelId?: string;
-	/** Default-surfaces only (owner, 2026-09-18): NO baked-in default —
-	 *  unset settings render "no model"/"—" (BYOK first boot), never the
-	 *  config pin. Chat surfaces keep the catalog-default fallback (the
-	 *  engine runs the pin, so the control shows what will run). */
-	noDefaultModel?: boolean;
-}) {
-	const catalog = useModelCatalog();
+/**
+ * THE STRONG-SLOT CONTROL (fix wave, owner ruling: "one and the same").
+ * The composer's model + thinking pills ARE the strong slot — the tier
+ * that runs prober + teacher. Reads: the raw models section (GET
+ * /api/settings) for the user's pick, plus the federated catalog for the
+ * menus. Writes: PUT /api/settings/models via composeSlotModel — the same
+ * seam the settings Agent section and the SetupDialog write, so there is
+ * exactly one strong slot in the world and every surface edits it.
+ *
+ * Unpicked reads "—" (the no-factory-fallback language: the UI never
+ * presents a default model; the engine-side pin still resolves, the UI
+ * never claims it). Legacy per-chat model overrides on old records keep
+ * resolving server-side — the UI simply no longer writes that field
+ * anywhere.
+ */
+export function ModelControl() {
+	const { catalog, refresh } = useModelCatalog();
+	const [models, setModels] = useState<ModelsSettings | undefined>();
 	const [open, setOpen] = useState<"model" | "thinking" | null>(null);
 	const [error, setError] = useState<string | null>(null);
 	const containerRef = useRef<HTMLDivElement>(null);
 
-	const defaults = catalog?.defaults;
-	const effectiveId = noDefaultModel
-		? settings?.model?.id
-		: (settings?.model?.id ?? defaults?.model.id ?? fallbackModelId);
-	const effectiveLevel = noDefaultModel
-		? settings?.thinkingLevel
-		: (settings?.thinkingLevel ?? defaults?.thinkingLevel);
-	const entry = catalog?.models.find((m) => m.id === effectiveId);
-	const levels = entry?.supportedLevels ?? [];
+	useEffect(() => {
+		let alive = true;
+		fetch("/api/settings")
+			.then((r) => r.json() as Promise<{ settings: { models?: ModelsSettings } | null }>)
+			.then((body) => alive && setModels(body.settings?.models ?? undefined))
+			.catch(() => {
+				/* the record fetch failing leaves the control read-only
+				   ("—" triggers, closed menus) — same posture as a
+				   catalog failure */
+			});
+		return () => {
+			alive = false;
+		};
+	}, []);
 
+	const override = models?.strong;
+	const effectiveId = override?.model?.id;
+	const effectiveProvider = override?.model?.provider;
+	const effectiveLevel = override?.thinkingLevel;
+	const entry = catalog?.models.find(
+		(m) => m.id === effectiveId && m.provider === effectiveProvider,
+	);
+	const levels = entry?.supportedLevels ?? [];
 
 	// The intuitive dropdown contract (owner, stats-control round 1): any
 	// click outside the open menu — or an Esc keypress — closes it. Only the
@@ -136,18 +144,14 @@ export function ModelControl({
 		};
 	}, [open]);
 
+	// One write seam: composeSlotModel preserves the cheap/vision siblings
+	// (replace-whole-section discipline) and the per-field independence of
+	// model + thinkingLevel within the strong slot.
 	const save = useCallback(
-		async (next: ChatSettings) => {
+		async (next: ModelsSettings) => {
 			setError(null);
-			// Home view (pre-chat): defer — the selection rides along on the
-			// chat POST and is PUT after creation (onSaved is still lifted).
-			if (!chatId) {
-				onSaved(next);
-				setOpen(null);
-				return;
-			}
 			try {
-				const res = await fetch(`/api/chats/${chatId}/settings`, {
+				const res = await fetch("/api/settings/models", {
 					method: "PUT",
 					headers: { "Content-Type": "application/json" },
 					body: JSON.stringify(next),
@@ -157,14 +161,13 @@ export function ModelControl({
 					setError(body.error ?? `settings rejected (${res.status})`);
 					return;
 				}
-				const { settings: saved } = (await res.json()) as { settings: ChatSettings };
-				onSaved(saved);
+				setModels(next);
 				setOpen(null);
 			} catch {
 				setError("Could not reach the server — try again.");
 			}
 		},
-		[chatId, onSaved],
+		[],
 	);
 
 	// Shortcut seams (keyboard wave A): ⌘K opens the model menu (the
@@ -175,63 +178,66 @@ export function ModelControl({
 		const onOpenPicker = () => {
 			setOpen("model");
 			setError(null);
+			refresh(); // mid-session key changes widen the menu (cache fix)
 		};
 		window.addEventListener("lh:kbd-open-model-picker", onOpenPicker);
 		return () => window.removeEventListener("lh:kbd-open-model-picker", onOpenPicker);
-	}, []);
+	}, [refresh]);
 
 	useEffect(() => {
 		const onCycleThinking = () => {
 			if (levels.length === 0) return;
 			const idx = effectiveLevel === undefined ? -1 : levels.indexOf(effectiveLevel);
-			void save({ ...(settings ?? {}), thinkingLevel: levels[(idx + 1) % levels.length] });
+			const next = levels[(idx + 1) % levels.length];
+			if (next === undefined) return;
+			void save(composeSlotModel(models, "strong", effectiveProvider ?? "", effectiveId ?? "", next));
 		};
 		window.addEventListener("lh:kbd-cycle-thinking", onCycleThinking);
 		return () => window.removeEventListener("lh:kbd-cycle-thinking", onCycleThinking);
-	}, [levels, effectiveLevel, save, settings]);
+	}, [levels, effectiveLevel, effectiveProvider, effectiveId, models, save]);
 
 	// Selecting a model (click and Enter share one path): keep the
 	// thinking level only when the new model supports it — otherwise
-	// drop it (config fallback clamps honestly; a carry-over would 400).
-	// Replace-whole discipline: spread the current settings — a model pick
-	// must not silently clear a sibling override (graphContextTokens).
+	// drop it (a carry-over would 400 at the server's catalog gate).
 	const pickModel = (m: ModelCatalogEntry) => {
 		const nextLevel =
-			effectiveLevel !== undefined && m.supportedLevels.includes(effectiveLevel)
-				? effectiveLevel
-				: undefined;
-		void save({ ...(settings ?? {}), model: { provider: m.provider, id: m.id }, thinkingLevel: nextLevel });
+			effectiveLevel !== undefined && m.supportedLevels.includes(effectiveLevel) ? effectiveLevel : undefined;
+		void save(composeSlotModel(models, "strong", m.provider, m.id, nextLevel ?? ""));
 	};
 
+	// Stale-while-revalidate on manual open too (⌘K covers the keyboard
+	// path above): the cached list shows instantly, the fresh federation
+	// swaps in when it lands.
+	const openMenu = (kind: "model" | "thinking") => {
+		setOpen((o) => (o === kind ? null : kind));
+		setError(null);
+		if (kind === "model") refresh();
+	};
 
 	return (
 		<div ref={containerRef} className="relative flex items-center gap-1.5" data-testid="model-control">
 			<button
 				type="button"
 				data-testid="stats-model"
-				onClick={() => {
-					setOpen((o) => (o === "model" ? null : "model"));
-					setError(null);
-				}}
+				onClick={() => openMenu("model")}
 				aria-expanded={open === "model"}
-				title="Conversation model — applies next turn"
+				title="Strong tier model (prober + teacher) — set app-wide"
 				className="flex items-center gap-1.5 rounded-full border border-border/60 bg-card/70 px-2.5 py-1 transition-colors hover:border-border hover:bg-muted"
 			>
 				<span className="text-card-foreground">{effectiveId ? prettyModel(effectiveId) : "—"}</span>
-					<span aria-hidden className="text-xs text-muted-foreground">▾</span>
+				<span aria-hidden className="text-xs text-muted-foreground">▾</span>
 			</button>
 			<button
 				type="button"
 				data-testid="stats-thinking"
 				onClick={() => {
-					// No model yet (noDefaultModel first boot) → nothing to set a
-					// level FOR: the click is a no-op, never an empty menu.
+					// No model picked → nothing to set a level FOR: the click
+					// is a no-op, never an empty menu.
 					if (entry === undefined) return;
-					setOpen((o) => (o === "thinking" ? null : "thinking"));
-					setError(null);
+					openMenu("thinking");
 				}}
 				aria-expanded={open === "thinking"}
-				title="Thinking level — applies next turn"
+				title="Strong tier thinking level — set app-wide"
 				className="flex items-center gap-1.5 rounded-full border border-border/60 bg-card/70 px-2.5 py-1 transition-colors hover:border-border hover:bg-muted"
 			>
 				{/* Just the level — the button reads like the model button reads
@@ -243,7 +249,8 @@ export function ModelControl({
 			</button>
 
 			{/* The shared dropdown body (extracted 2026-09-20): the agent
-			    settings' role selects use the exact same one. */}
+			    settings' slot selects and the setup dialog use the exact same
+			    one. */}
 			{open === "model" && (
 				<div
 					data-testid="model-menu"
@@ -253,8 +260,13 @@ export function ModelControl({
 					<ModelMenuList
 						models={catalog?.models}
 						effectiveId={effectiveId}
+						effectiveProvider={effectiveProvider}
 						onPick={pickModel}
-						footer="Applies to the next turn · background agents stay config-pinned"
+						footer={
+							catalog && catalog.models.length === 0
+								? "No models — add a provider key in Keys"
+								: "Strong tier — runs prober + teacher, app-wide"
+						}
 					/>
 				</div>
 			)}
@@ -267,7 +279,9 @@ export function ModelControl({
 					<ThinkingMenuList
 						levels={catalog ? levels : []}
 						effectiveLevel={effectiveLevel}
-						onPick={(level) => void save({ ...(settings ?? {}), thinkingLevel: level as ChatSettings["thinkingLevel"] })}
+						onPick={(level) =>
+							void save(composeSlotModel(models, "strong", effectiveProvider ?? "", effectiveId ?? "", level as ThinkingLevel))
+						}
 						empty={catalog ? (effectiveId ? `${prettyModel(effectiveId)} has no thinking levels.` : "Pick a model first.") : "Loading…"}
 						footer="Levels this model actually supports"
 					/>

components/new-session.tsx

@@ -125,10 +125,6 @@ export function DraftShell({
 								<StatsBar
 									dictationSlot={<DictationBar dictation={dictation} />}
 									turns={[]}
-									chatId=""
-									noDefaultModel
-									settings={settings}
-									onSettingsSaved={onSettingsSaved}
 									// The session-data slot (owner, 2026-09-15): pre-chat the left
 									// side is free — the knowledge-context budget lives exactly
 									// where session data will sit once a session exists.
@@ -161,11 +157,10 @@ export function NewSession({
 	const [text, setText] = useState("");
 	const [busy, setBusy] = useState(false);
 	// THE default settings (owner, 2026-09-18): this surface and the home
-	// topic dock ARE the settings page for the default model — no baked-in
-	// default exists; the user's last choice (server-rendered in via
-	// initialSettings, shared with home through data/default-settings.json)
-	// IS the default. ModelControl with an empty chatId never PUTs — it
-	// hands the choice up; it still rides the session POST then PUT-on-create.
+	// topic dock carries only the knowledge-context budget now (fix
+	// wave): the model pills ARE the strong slot (PUT /api/settings/models,
+	// app-wide) — the per-chat model pick is retired. saveDraft still
+	// lifts the context budget so it rides the session POST.
 	const { settings, save: saveDraft } = useDefaultSettings(initialSettings);
 
 	// First-run gate (model-slots wave, owner 2026-09-20): the send

components/settings/agent-section.tsx

@@ -388,12 +388,16 @@ export function AgentSection({
 			.then((body: { prober: SegmentInfo[]; teacher: SegmentInfo[] }) => setPrompts(body));
 	}
 
-	/** The pinned Default row — clears this control's override (absent key
-	 *  = the factory pin). Same row language as the shared menu's list rows. */
-	const defaultRow = (active: boolean, onPick: () => void) => (
+	/** The "—" row — THINKING menus only: clears the thinking pin (the
+	 *  slot keeps its model; the tier's resolved budget takes over). Model
+	 *  menus carry no such row — unpicking a model would re-arm the
+	 *  first-run gate, and a "default" model is not a thing in this app
+	 *  (owner, fix wave: no factory fallback is ever presented as a
+	 *  choice; an unpicked slot just reads "—"). */
+	const noneRow = (active: boolean, onPick: () => void) => (
 		<button
 			type="button"
-			data-testid="menu-default"
+			data-testid="menu-none"
 			onClick={onPick}
 			className={`flex w-full items-center justify-between rounded-lg px-2 py-1.5 text-left transition-colors hover:bg-muted ${
 				active ? "bg-muted/60 text-card-foreground" : "text-card-foreground"
@@ -514,10 +518,12 @@ export function AgentSection({
 					const modelId = override?.model?.id ?? "";
 					const provider = override?.model?.provider ?? "";
 					const thinking = override?.thinkingLevel ?? "";
-					// The tier's resolved pin (override → factory): the Default
-					// hint names it; the thinking list resolves from its levels.
+					// The tier's resolved pin is machinery only now (owner, fix
+					// wave): the UI never names the factory fallback — the hint
+					// carries the roster, the triggers read "—" when unpicked — but
+					// the pin still governs the thinking level LIST when no override
+					// names a model to read levels from.
 					const pin = slots?.[slot];
-					const defaultName = pin ? prettyModel(pin.model.id) : "config pin";
 					// The model whose levels govern the thinking list: the
 					// override, else the resolved pin (when it's in the federated
 					// catalog); the standard ladder as the last fallback.
@@ -532,7 +538,7 @@ export function AgentSection({
 						<SettingsRow
 							key={slot}
 							label={SLOT_META[slot].label}
-							hint={`${SLOT_META[slot].roster} · default: ${defaultName}`}
+							hint={SLOT_META[slot].roster}
 							testid={`slot-row-${slot}`}
 						>
 							{/* The anchor for the outside-click contract is the
@@ -543,7 +549,7 @@ export function AgentSection({
 							>
 								<MenuTrigger
 									value={modelId ? prettyModel(modelId) : ""}
-									emptyLabel="Default"
+									emptyLabel="—"
 									ariaLabel={`${SLOT_META[slot].label} model`}
 									testid={`slot-model-${slot}`}
 									open={thisMenuOpen === "model"}
@@ -552,7 +558,7 @@ export function AgentSection({
 								/>
 								<MenuTrigger
 									value={thinking}
-									emptyLabel="Default"
+									emptyLabel="—"
 									ariaLabel={`${SLOT_META[slot].label} thinking`}
 									testid={`slot-thinking-${slot}`}
 									open={thisMenuOpen === "thinking"}
@@ -565,17 +571,10 @@ export function AgentSection({
 										testid={`slot-model-menu-${slot}`}
 										menuClass="flex w-[22rem] flex-col rounded-xl border border-border bg-card p-2 text-xs shadow-xl"
 									>
-										{defaultRow(
-											modelId === "",
-											() => {
-												onModelsChange(composeSlotModel(models, slot, "", "", thinking));
-												setOpenMenu(null);
-											},
-										)}
 										<ModelMenuList
 											models={slotCatalog ?? undefined}
-											effectiveId={modelId || pin?.model.id}
-											effectiveProvider={provider || pin?.model.provider}
+											effectiveId={modelId}
+											effectiveProvider={provider}
 											onPick={(entry) => {
 												onModelsChange(composeSlotModel(models, slot, entry.provider, entry.id, thinking));
 												setOpenMenu(null);
@@ -594,7 +593,7 @@ export function AgentSection({
 										testid={`slot-thinking-menu-${slot}`}
 										menuClass="flex w-44 flex-col gap-0.5 rounded-xl border border-border bg-card p-2 text-xs shadow-xl"
 									>
-										{defaultRow(
+										{noneRow(
 											thinking === "",
 											() => {
 												onModelsChange(composeSlotModel(models, slot, provider, modelId, ""));

components/stats-bar.tsx

@@ -29,24 +29,10 @@ import { ModelControl } from "@/components/model-picker";
  */
 export function StatsBar({
 	turns,
-	chatId,
-	settings,
-	onSettingsSaved,
 	leftSlot,
 	dictationSlot,
-	noDefaultModel,
 }: {
 	turns: TurnUsage[];
-	chatId: string;
-	settings?: ChatSettings;
-	onSettingsSaved: (settings: ChatSettings) => void;
-	/** Default-surfaces only (owner, 2026-09-18): there is NO baked-in
-	 *  default model — BYOK first boot shows "no model" until the user
-	 *  picks one, and that pick IS the default from then on. Chat surfaces
-	 *  keep the catalog-default fallback (the engine runs the config pin
-	 *  when a session record has no override — the control shows what will
-	 *  actually run). */
-	noDefaultModel?: boolean;
 	/** Pre-chat only: replaces the (empty) session-data summary — home and
 	 *  the /chat/new draft mount the knowledge-context slider here. */
 	leftSlot?: ReactNode;
@@ -178,13 +164,7 @@ export function StatsBar({
 			{/* The model + thinking control — one controller for the conversation
 			    agents (prober/teacher); the record's `turns` above still folds
 			    the ACTUAL models billed, regardless of what the picker says. */}
-			<ModelControl
-				chatId={chatId}
-				settings={settings}
-				onSaved={onSettingsSaved}
-				fallbackModelId={lastModel}
-				noDefaultModel={noDefaultModel}
-			/>
+			<ModelControl />
 		</div>
 	);
 }

src/server/model-catalog.ts

@@ -1,17 +1,20 @@
 /**
- * The model catalog's server surface (model-control wave, 2026-09-12):
- * pi-ai's shipped OpenRouter catalog projected to client-safe DTOs for the
- * picker (GET /api/models), plus the validation gate for per-chat settings
- * (PUT /api/chats/[id]/settings).
+ * The model catalog's server surface (model-control wave, 2026-09-12;
+ * federated since the model-slots wave, 2026-09-20): pi-ai's catalog for
+ * every KEYED provider, projected to client-safe DTOs for the picker (GET
+ * /api/models), plus the validation gate for settings writes (PUT
+ * /api/settings/* — the per-chat settings PUT is retired from the UI;
+ * legacy records' per-chat overrides still resolve server-side).
  *
  * pi-ai owns ALL the data: the catalog (id/name/cost/context/modality/
  * thinkingLevelMap) and the per-model thinking truth
  * (getSupportedThinkingLevels / clampThinkingLevel). This module only
  * projects and validates — no second registry to drift out of sync.
  *
- * Multi-provider future: `getModels()` is called per configured provider,
- * so a second provider (pi-ai ships ~30) appears in the picker by adding
- * it to piModels() in src/agent/models.ts — nothing here changes.
+ * Federation: `getModels()` is called per keyed provider (federated, the
+ * model-slots wave), so a provider appears in the picker exactly when its
+ * key is present — piModels() in src/agent/models.ts owns the provider
+ * set; nothing here changes.
  */
 
 import { getSupportedThinkingLevels, type Api, type Model } from "@earendil-works/pi-ai";

tests/render-settings.test.tsx

@@ -59,7 +59,7 @@ describe("SettingsDialog (the designed surface, SSR)", () => {
 });
 
 describe("AgentSection (thin SSR)", () => {
-	it("renders the three model SLOT rows (slots-only, owner ruling 2026-09-20), Default-triggered dropdowns", () => {
+	it("renders the three model SLOT rows (slots-only, fix wave: unpicked reads —, no Default option)", () => {
 		const html = renderToStaticMarkup(<AgentSection agent={undefined} models={undefined} onSectionChange={() => {}} onModelsChange={() => {}} />);
 		for (const slot of ["strong", "cheap", "vision"]) {
 			assert.ok(html.includes(`data-testid="slot-row-${slot}"`), slot);
@@ -70,7 +70,12 @@ describe("AgentSection (thin SSR)", () => {
 			// the roster hint rides every row
 			assert.ok(html.includes("Prober + Teacher") || slot !== "strong", "strong roster");
 		}
-		assert.equal((html.match(/>Default<\/span>/g) ?? []).length, 6, "three slots × two Default triggers");
+		// Fix wave: no Default anywhere — an unpicked slot reads "—"
+		// (the owner's no-factory-fallback language), and no menu
+		// carries a Default row (menu-default testid is retired).
+		assert.equal((html.match(/>Default<\/span>/g) ?? []).length, 0, "no Default trigger");
+		assert.ok(!html.includes('data-testid="menu-default"'), "no Default row");
+		assert.equal((html.match(/>—<\/span>/g) ?? []).length, 6, "three slots × two — triggers");
 		// the per-role rows are GONE (slots-only)
 		for (const role of ["researcher", "demoBuilder", "visualMaker"]) {
 			assert.ok(!html.includes(`data-testid="role-row-${role}"`), `${role} retired`);

tests/render-stats-bar.test.tsx

@@ -24,12 +24,10 @@ function turn(over: Partial<TurnUsage> = {}): TurnUsage {
 	};
 }
 
-const SETTINGS_STUB = (_s: ChatSettings) => {};
-
 describe("stats bar", () => {
 	it("renders — everywhere when the record has no turns yet (doctrine)", () => {
 		const html = renderToStaticMarkup(
-			<StatsBar turns={[]} chatId="chat_x" onSettingsSaved={SETTINGS_STUB} />,
+			<StatsBar turns={[]} />,
 		);
 		assert.match(html, /data-testid="stats-bar"/);
 		assert.match(html, /data-testid="stats-context">—</);
@@ -47,7 +45,7 @@ describe("stats bar", () => {
 
 	it("folds context + cost from the turns log (core/prices, no local math)", () => {
 		const html = renderToStaticMarkup(
-			<StatsBar turns={[turn(), turn()]} chatId="chat_x" onSettingsSaved={SETTINGS_STUB} />,
+			<StatsBar turns={[turn(), turn()]} />,
 		);
 		// last turn's last call: 10k in + 1k out = 11k; pi catalog limit
 		// 1_048_576 → "1M" (tables regenerated from pi-ai's catalog)
@@ -55,14 +53,15 @@ describe("stats bar", () => {
 		// pi catalog price 0.075/0.25 per 1M: each turn 10k×0.075 + 1k×0.25
 		// = $0.001 → two = $0.0020
 		assert.match(html, /data-testid="stats-cost">\$0\.0020</);
-		// model button label falls back to the last turn's actual model
-		// (the catalog + settings are what drive it once loaded)
-		assert.match(html, /data-testid="stats-model"[^>]*>\s*<span[^>]*>Glm 5\.3 Flash<\/span>/);
+		// model button label: SSR (record fetch not run yet) reads "—" —
+		// the strong slot arrives client-side via GET /api/settings; the
+		// turn log below still folds the ACTUAL models billed
+		assert.match(html, /data-testid="stats-model"[^>]*>\s*<span[^>]*>—<\/span>/);
 	});
 
 	it("shows — for cost when every turn is unpriceable, never a fake $0", () => {
 		const html = renderToStaticMarkup(
-			<StatsBar turns={[turn({ model: "nope/unknown" })]} chatId="chat_x" onSettingsSaved={SETTINGS_STUB} />,
+			<StatsBar turns={[turn({ model: "nope/unknown" })]} />,
 		);
 		assert.match(html, /data-testid="stats-cost">—</);
 		// unknown model also kills the context limit