@@ -33,53 +33,6 @@ export type AnthropicProviderReasoningParams =
 
 export type OpenAiReasoningParams = { reasoning_effort: OpenAI.Chat.ChatCompletionCreateParams["reasoning_effort"] }
 
-/**
- * DTE series 2/5 — effort levels accepted by the Claude 4.7+ adaptive-thinking
- * `output_config.effort` envelope. Efforts outside this set (e.g. "none",
- * "minimal", "disable") omit the envelope so the API applies its own default.
- * @internal Exported for focused implementation tests.
- */
-export const ADAPTIVE_OUTPUT_CONFIG_EFFORTS: readonly ReasoningEffortExtended[] = [
-	"low",
-	"medium",
-	"high",
-	"xhigh",
-	"max",
-]
-
-/**
- * DTE series 2/5 — resolves the effective thinking effort for a single request.
- *
- * Resolution order (strongest first):
- * 1. `override` — the per-request task-local effort
- *    (`ApiHandlerCreateMessageMetadata.reasoningEffort`),
- * 2. `settingsReasoningEffort` — the settings-derived value,
- * 3. `modelDefaultEffort` — the model's default effort.
- *
- * This is the single shared resolution point for the per-request override:
- * providers that resolve the effective effort through it inherit the override
- * without duplicating precedence logic. The override is transient (next request
- * only) and never persisted to settings.
- * @internal Exported for focused implementation tests.
- */
-export const resolveEffectiveReasoningEffort = ({
-	override,
-	settingsReasoningEffort,
-	modelDefaultEffort,
-}: {
-	override?: ReasoningEffortExtended
-	settingsReasoningEffort?: ReasoningEffortExtended | "disable"
-	modelDefaultEffort?: ReasoningEffortExtended
-}): ReasoningEffortExtended | "disable" | undefined => {
-	if (override !== undefined) {
-		return override
-	}
-	if (settingsReasoningEffort !== undefined) {
-		return settingsReasoningEffort
-	}
-	return modelDefaultEffort
-}
-
 // Valid Gemini thinking levels for effort-based reasoning
 const GEMINI_THINKING_LEVELS = ["minimal", "low", "medium", "high"] as const
 
 
@@ -419,11 +419,6 @@ export const stories: Record<string, Story> = {
 		const { UISettingsStory } = await import("@/components/settings/__tests__/UISettings.visual.fixture")
 		return <UISettingsStory />
 	},
-	"experimental-settings": async () => {
-		const { ExperimentalSettingsStory } =
-			await import("@/components/settings/__tests__/ExperimentalSettings.visual.fixture")
-		return <ExperimentalSettingsStory />
-	},
 	"ui-settings-long-locale": async () => {
 		const { UISettingsStory } = await import("@/components/settings/__tests__/UISettings.visual.fixture")
 		return <UISettingsStory initialState={{ language: "ru" }} />
 
@@ -47,15 +47,6 @@ describe("TranslationProvider locale loading", () => {
 		// through the English fallback and the switch lands after the fetch.
 		expect(screen.getByTestId("error-title")).toHaveTextContent("Something went wrong")
 
-		// A locale outside the entry chunk is fetched on demand, so how long the switch
-		// takes is a property of the machine and the load on it, not of the code under
-		// test: on a contended runner the fetch can outlast any fixed wall-clock window,
-		// which is what made this suite flake. Awaiting the memoized promise the provider
-		// itself waits on - the idiom the unmount case at the end of this file uses - takes
-		// the clock out of the assertion. What `waitFor` has left to catch is the render
-		// that `languageChanged` triggers, which settles in the same task.
-		await loadLanguage("ko")
-
 		await waitFor(() => {
 			expect(screen.getByTestId("error-title")).toHaveTextContent("문제가 발생했습니다")
 		})
@@ -76,9 +67,6 @@ describe("TranslationProvider locale loading", () => {
 			)
 		})
 
-		// Await the fetch instead of racing a fixed window (note in the first case).
-		await loadLanguage("ja")
-
 		await waitFor(() => {
 			expect(screen.getByTestId("error-title")).toHaveTextContent("問題が発生しました")
 		})
@@ -96,9 +84,6 @@ describe("TranslationProvider locale loading", () => {
 	it("keeps English available after switching away and back", async () => {
 		const { rerender } = renderProbe("de")
 
-		// German is loaded on demand as well: await it rather than time it.
-		await loadLanguage("de")
-
 		await waitFor(() => {
 			expect(screen.getByTestId("error-title")).toHaveTextContent("Etwas ist schiefgelaufen")
 		})
@@ -120,9 +105,6 @@ describe("TranslationProvider locale loading", () => {
 	it("keeps the previous locale rendered while a warm switch is still loading", async () => {
 		const { rerender } = renderProbe("de")
 
-		// The cold locale is awaited here too (see the note in the first case).
-		await loadLanguage("de")
-
 		await waitFor(() => {
 			expect(screen.getByTestId("error-title")).toHaveTextContent("Etwas ist schiefgelaufen")
 		})
@@ -141,10 +123,6 @@ describe("TranslationProvider locale loading", () => {
 		// resolves would paint the English fallback here instead of German.
 		expect(screen.getByTestId("error-title")).toHaveTextContent("Etwas ist schiefgelaufen")
 
-		// Awaiting the fetch through the promise the provider waits on keeps the assertion
-		// above a statement about ordering rather than about the clock.
-		await loadLanguage("fr")
-
 		await waitFor(() => {
 			expect(screen.getByTestId("error-title")).toHaveTextContent("Une erreur s'est produite")
 		})