.ai/conventions/data.md

@@ -70,7 +70,7 @@ Network/unknown error получает безопасное локальное
 
 Если одна группа API codes требует одинакового recovery в нескольких views,
 сведи классификацию у ближайшего общего owner. Не размножай magic comparisons
-и не объявляй закрытый frontend error enum: generated `code` пока `string`.
+и используй `ApiErrorCode` для известных значений: generated `code` остаётся `string`.
 Неизвестный новый code должен сохранять fallback. Рефакторинг существующих
 разных recovery paths требует behavior proof, а не общей обработки всех ошибок.
 

.ai/conventions/engineering.md

@@ -29,7 +29,8 @@ owner и 1–3 примера. Код показывает механизм; с
 ## Domain values
 
 Finite business vocabulary принадлежит одному domain/module/entity owner.
-Переиспользуй его symbols; для нового словаря без аналога — `as const` + union.
+Переиспользуй его symbols; для machine codes и protocol values используй
+строковые `enum`, для структуры с разными payload — discriminated union.
 Сохраняй wire values; generated/external enums не переписывай вручную.
 Numeric policy называй по смыслу и единицам. Индексы, `Math.max(value, 0)` и
 обычные labels не выноси в constants без semantic benefit.

.ai/conventions/typescript-react.md

@@ -5,7 +5,8 @@
 - Сохраняй strict TS profile и `import type`. Для недоверенного значения используй
   `unknown` с narrowing; `any` не заменяет DTO/validation. Локальное исключение
   на нетипизированной boundary должно быть узким и объяснённым.
-- `enum` и `namespace` не используются: frontend имеет `erasableSyntaxOnly`.
+- Строковые `enum` используются для machine codes и protocol values.
+  `namespace` не используется; tooling сохраняет `erasableSyntaxOnly`.
   Для состояния с разными payload выбирай discriminated union; не добавляй
   необязательные поля, допускающие невозможные комбинации.
 - Named components — const-valued `FC<Props>`; named props находятся рядом или
@@ -33,19 +34,23 @@ Container/VM/view и state owners — в [UI](ui.md).
 
 Общее правило ownership и символических значений —
 [Domain values](engineering.md#domain-values).
-Backend vocabulary бери из generated `paths`, не создавай ручную копию enum.
-Текущий `schema.d.ts` содержит только types: typed wire literals допустимы,
-когда generator не предоставляет runtime values.
+Backend vocabulary бери из generated `paths`; generated artifacts вручную не меняй.
+Для открытых `string` полей допускается локальный enum известных значений,
+используемых UI. Он не закрывает wire contract и сохраняет unknown fallback.
+Если generator предоставляет runtime enum, используй его.
 
-`ProblemDetailsDto.code` сейчас `string`. Не объявляй закрытый frontend error
-enum и не превращай неизвестный code в известный через cast. Повторяющуюся
+`ProblemDetailsDto.code` сейчас `string`. `ApiErrorCode` перечисляет известные UI коды, а не закрывает wire contract.
+`apiErrorCode` сохраняет произвольную строку; `isApiErrorCode` проверяет известное
+значение без cast и сохраняет fallback для неизвестного кода. Повторяющуюся
 обработку своди у ответственного owner; [errors](data.md#errors).
 
 `@typescript-eslint/no-magic-numbers` — error; fixtures/tests/stories исключены
 из этой дополнительной проверки. Policy получает имя и единицы; подавление допустимо для
 incidental value с объяснением. Обычный UI-текст не превращай в constant:
 его owner — [i18n](ui.md#строки-и-валидация).
-Semantic magic strings и props profile требуют review.
+`no-restricted-syntax` запрещает inline machine codes и protocol values в production;
+`no-unsafe-enum-comparison` проверяет сравнения enum. Fixtures/stories сохраняют
+literal wire values. Новые vocabularies и props profile требуют review.
 
 ## Проверка
 

eslint.config.mjs

@@ -118,4 +118,45 @@ export default defineConfig(
 		files: ["**/*.stories.tsx", ".storybook/preview.tsx"],
 		rules: { "import-x/exports-last": "off", "import-x/no-default-export": "off" },
 	},
+	{
+		files: [
+			"src/**/*.{ts,tsx}",
+			"packages/*/src/**/*.{ts,tsx}",
+		],
+		ignores: [
+			"**/*.test.{ts,tsx}",
+			"**/*.stories.tsx",
+			"src/test/**",
+		],
+		rules: {
+			"@typescript-eslint/no-unsafe-enum-comparison": "error",
+			"no-restricted-syntax": [
+				"error",
+				{
+					message: "Use the owning enum member for machine codes and protocol values.",
+					selector: "Literal[value=/^(?:(?:INSTRUMENT_ID_TYPE|INSTRUMENT_TYPE|OPERATION_STATE|OPERATION_TYPE|ACCOUNT_STATUS|ACCOUNT_TYPE|CANDLE_INTERVAL|COUPON_TYPE|BANK|INVALID)_[A-Z0-9]+(?:_[A-Z0-9]+)*|[A-Z][A-Z0-9_]*_(?:ERROR|UNAVAILABLE|NOT_FOUND|NOT_CONNECTED|CONFLICT|AMBIGUOUS|REGISTERED)|P[0-9]{4}|UNAUTHORIZED|FORBIDDEN|BAD_REQUEST|NOT_FOUND|UNSUPPORTED_MEDIA_TYPE)$/]:not(TSEnumMember > Literal)",
+				},
+				{
+					message: "Use the owning enum member instead of a template machine code.",
+					selector: "TemplateElement[value.cooked=/^(?:(?:INSTRUMENT_ID_TYPE|INSTRUMENT_TYPE|OPERATION_STATE|OPERATION_TYPE|ACCOUNT_STATUS|ACCOUNT_TYPE|CANDLE_INTERVAL|COUPON_TYPE|BANK|INVALID)_[A-Z0-9]+(?:_[A-Z0-9]+)*|[A-Z][A-Z0-9_]*_(?:ERROR|UNAVAILABLE|NOT_FOUND|NOT_CONNECTED|CONFLICT|AMBIGUOUS|REGISTERED)|P[0-9]{4}|UNAUTHORIZED|FORBIDDEN|BAD_REQUEST|NOT_FOUND|UNSUPPORTED_MEDIA_TYPE)$/]:not(TSEnumMember TemplateElement)",
+				},
+				{
+					message: "Use an enum member instead of an inline code or protocol value.",
+					selector: "Property:matches([key.name=/^(code|errorCode|idType|instrumentKind)$/], [key.value=/^(code|errorCode|idType|instrumentKind)$/]) > Literal.value[value=type(string)]",
+				},
+				{
+					message: "Use an enum member instead of constructing a code or protocol value.",
+					selector: "Property:matches([key.name=/^(code|errorCode|idType|instrumentKind)$/], [key.value=/^(code|errorCode|idType|instrumentKind)$/]) > TemplateLiteral.value",
+				},
+				{
+					message: "Use a computed enum member as the protocol mapping key.",
+					selector: "Property[computed=false][key.name=/^(OPERATION_TYPE|ACCOUNT_TYPE)_/]",
+				},
+				{
+					message: "Compare codes with their enum members, not string literals.",
+					selector: "BinaryExpression:has(> :matches(MemberExpression[property.name=/^(code|errorCode)$/], Identifier[name=/^(code|errorCode)$/])) > Literal[value=type(string)]",
+				},
+			],
+		},
+	},
 );

scripts/test-eslint.mjs

@@ -185,3 +185,27 @@ test("ESLint formatting preserves spaces around JSX text and interpolations", as
 	assert.equal(fixed.errorCount, 0);
 	assert.ok(fixed.output?.includes("Amount: {value} / {value}"));
 });
+
+// Single-use codes must be caught too; fixture literals remain independent wire assertions.
+test("machine codes require enum members without banning ordinary text or Prisma selects", async () => {
+	const eslint = new ESLint();
+	const filePath = "src/shared/api/problem-details.ts";
+	for (const code of ["export function check(code: string) { return code === \"one-off-code\"; }", "export const result = `MOEX_UNAVAILABLE`;", "export const result = { code: \"one-off-code\" };", "export const result = { \"errorCode\": \"one-off-code\" };", "export const result = { code: `dynamic-${Date.now()}` };", "export const result = \"MOEX_UNAVAILABLE\";", "export const result = [\"INSTRUMENT_ID_TYPE_FIGI\"];", "export const result = { OPERATION_TYPE_COUPON: \"income\" };"]) {
+		const [result] = await eslint.lintText(code, { filePath });
+		assert.equal(result.fatalErrorCount, 0, code);
+		assert.ok(result.messages.some(({ ruleId }) => ruleId === "no-restricted-syntax"), code);
+	}
+	for (const code of [
+		"enum Code { Unavailable = \"MOEX_UNAVAILABLE\" } export const result = { code: Code.Unavailable };",
+		"export const select = { code: true, errorCode: true };",
+		"export const label = \"Please try again\"; export const key = \"JWT_SECRET\";",
+	]) {
+		const [result] = await eslint.lintText(code, { filePath });
+		assert.equal(result.fatalErrorCount, 0, code);
+		assert.ok(result.messages.every(({ ruleId }) => ruleId !== "no-restricted-syntax"), code);
+	}
+	const [fixture] = await eslint.lintText("export const result = { code: \"MOEX_UNAVAILABLE\" };", { filePath: "src/shared/api/client.test.ts" });
+	assert.ok(fixture.messages.every(({ ruleId }) => ruleId !== "no-restricted-syntax"));
+	const [comparison] = await eslint.lintText("enum Code { Ready = \"ready\" } export function check(code: Code) { return code === \"ready\"; }", { filePath });
+	assert.ok(comparison.messages.some(({ ruleId }) => ruleId === "@typescript-eslint/no-unsafe-enum-comparison"));
+});

src/entities/bank-card/api/mutations.ts

@@ -1,6 +1,6 @@
 import { useMutation, useQueryClient } from "@tanstack/react-query";
 
-import { apiClient, apiErrorCode } from "@/shared/api";
+import { apiClient, ApiErrorCode, apiErrorCode, isApiErrorCode } from "@/shared/api";
 
 import type {
 	CreateBankCard,
@@ -34,14 +34,15 @@ function useBankMutations() {
 		});
 	const options = {
 		onError: (error: unknown) => {
+			const errorCode = apiErrorCode(error);
 			if (
 				[
-					"BANK_DEPENDENT_REFUNDS",
-					"BANK_INTENT_CONFLICT",
-					"BANK_REFUND_LIMIT",
-					"BANK_VERSION_CONFLICT",
-					"BANK_WRITE_CONFLICT",
-				].includes(apiErrorCode(error) ?? "")
+					ApiErrorCode.BankDependentRefunds,
+					ApiErrorCode.BankIntentConflict,
+					ApiErrorCode.BankRefundLimit,
+					ApiErrorCode.BankVersionConflict,
+					ApiErrorCode.BankWriteConflict,
+				].some(code => isApiErrorCode(errorCode, code))
 			)
 				return invalidate();
 		},

src/entities/broker-operation/model/display.test.ts

@@ -0,0 +1,23 @@
+import { expect, it } from "vitest";
+
+import { operationLabelKey } from "./display";
+
+it.each([
+	["OPERATION_TYPE_BUY", "buy"],
+	["OPERATION_TYPE_BUY_CARD", "buy"],
+	["OPERATION_TYPE_BUY_MARGIN", "buy"],
+	["OPERATION_TYPE_SELL", "sell"],
+	["OPERATION_TYPE_SELL_CARD", "sell"],
+	["OPERATION_TYPE_SELL_MARGIN", "sell"],
+	["OPERATION_TYPE_DIV_EXT", "dividend"],
+	["OPERATION_TYPE_DIVIDEND", "dividend"],
+	["OPERATION_TYPE_DIVIDEND_TRANSFER", "dividend"],
+	["OPERATION_TYPE_INPUT_SECURITIES", "input"],
+	["OPERATION_TYPE_OUTPUT_SECURITIES", "output"],
+	["OPERATION_TYPE_FUTURE_TAX", "tax"],
+	["OPERATION_TYPE_FUTURE_FEE", "fee"],
+	["OPERATION_TYPE_TRANS_FUTURE", "transfer"],
+	["FUTURE_UNKNOWN_OPERATION", "other"],
+])("preserves the wire operation label for %s", (type, label) => {
+	expect(operationLabelKey(type)).toBe(`ledger.operationType.${label}`);
+});

src/entities/broker-operation/model/display.ts

@@ -2,6 +2,23 @@ import { formatMoney } from "@/shared/lib";
 
 import type { BrokerageOperation } from "../api/useBrokerageOperations";
 
+enum OperationType {
+	Buy = "OPERATION_TYPE_BUY",
+	BuyCard = "OPERATION_TYPE_BUY_CARD",
+	BuyMargin = "OPERATION_TYPE_BUY_MARGIN",
+	Coupon = "OPERATION_TYPE_COUPON",
+	DivExtension = "OPERATION_TYPE_DIV_EXT",
+	Dividend = "OPERATION_TYPE_DIVIDEND",
+	DividendTransfer = "OPERATION_TYPE_DIVIDEND_TRANSFER",
+	InputSecurities = "OPERATION_TYPE_INPUT_SECURITIES",
+	OutputSecurities = "OPERATION_TYPE_OUTPUT_SECURITIES",
+	Sell = "OPERATION_TYPE_SELL",
+	SellCard = "OPERATION_TYPE_SELL_CARD",
+	SellMargin = "OPERATION_TYPE_SELL_MARGIN",
+}
+
+const operationTransferPrefix = "OPERATION_TYPE_TRANS_";
+
 type PaymentPresentation = {
 	amount: string;
 	label: string;
@@ -10,12 +27,16 @@ type PaymentPresentation = {
 
 function entryLabelKey(operation: BrokerageOperation): string {
 	if (operation.category === "income")
-		return operation.type === "OPERATION_TYPE_COUPON"
+		return isOperationType(operation.type, OperationType.Coupon)
 			? "ledger.entryLabel.income.coupon"
 			: "ledger.entryLabel.income.dividend";
 	return `ledger.category.${operation.category}`;
 }
 
+function isOperationType(value: unknown, expected: OperationType): boolean {
+	return value === expected;
+}
+
 function isZeroDecimal(value: string): boolean {
 	return /^-?0$|^-?0\.0+$/.test(value);
 }
@@ -23,35 +44,35 @@ function isZeroDecimal(value: string): boolean {
 function operationLabelKey(type: string): string {
 	if (
 		[
-			"OPERATION_TYPE_BUY",
-			"OPERATION_TYPE_BUY_CARD",
-			"OPERATION_TYPE_BUY_MARGIN",
-		].includes(type)
+			OperationType.Buy,
+			OperationType.BuyCard,
+			OperationType.BuyMargin,
+		].some(candidate => isOperationType(type, candidate))
 	)
 		return "ledger.operationType.buy";
 	if (
 		[
-			"OPERATION_TYPE_SELL",
-			"OPERATION_TYPE_SELL_CARD",
-			"OPERATION_TYPE_SELL_MARGIN",
-		].includes(type)
+			OperationType.Sell,
+			OperationType.SellCard,
+			OperationType.SellMargin,
+		].some(candidate => isOperationType(type, candidate))
 	)
 		return "ledger.operationType.sell";
 	if (
 		[
-			"OPERATION_TYPE_DIV_EXT",
-			"OPERATION_TYPE_DIVIDEND",
-			"OPERATION_TYPE_DIVIDEND_TRANSFER",
-		].includes(type)
+			OperationType.DivExtension,
+			OperationType.Dividend,
+			OperationType.DividendTransfer,
+		].some(candidate => isOperationType(type, candidate))
 	)
 		return "ledger.operationType.dividend";
 	if (type.includes("TAX")) return "ledger.operationType.tax";
 	if (type.includes("FEE")) return "ledger.operationType.fee";
-	if (type === "OPERATION_TYPE_INPUT_SECURITIES")
+	if (isOperationType(type, OperationType.InputSecurities))
 		return "ledger.operationType.input";
-	if (type === "OPERATION_TYPE_OUTPUT_SECURITIES")
+	if (isOperationType(type, OperationType.OutputSecurities))
 		return "ledger.operationType.output";
-	return type.startsWith("OPERATION_TYPE_TRANS_") ? "ledger.operationType.transfer" : "ledger.operationType.other";
+	return type.startsWith(operationTransferPrefix) ? "ledger.operationType.transfer" : "ledger.operationType.other";
 }
 
 function paymentPresentation(

src/features/instrument-details/model/useInstrumentOperations.ts

@@ -6,7 +6,7 @@ import {
 	type OperationCategory,
 	useBrokerageOperations,
 } from "@/entities/broker-operation";
-import { apiErrorCode } from "@/shared/api";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "@/shared/api";
 
 function useInstrumentOperations(
 	uid: string,
@@ -26,7 +26,7 @@ function useInstrumentOperations(
 		cursor: cursors.at(-1),
 	});
 	const retry = (retryScreen: () => unknown) => {
-		if (apiErrorCode(operations.error) === "INVALID_OPERATIONS_CURSOR") {
+		if (isApiErrorCode(apiErrorCode(operations.error), ApiErrorCode.InvalidOperationsCursor)) {
 			setPagination({ cursors: [], scope });
 			void client.invalidateQueries({
 				exact: true,

src/features/tbank-connection/model/screen-sync.ts

@@ -2,9 +2,11 @@ import { type QueryKey, useQueryClient } from "@tanstack/react-query";
 import { useEffect, useLayoutEffect, useRef, useState } from "react";
 
 import {
+	ApiErrorCode,
 	apiErrorCode,
 	apiQueryClient,
 	invalidateResourceAccess,
+	isApiErrorCode,
 	type paths,
 	useAuthenticatedQueries,
 } from "@/shared/api";
@@ -112,7 +114,7 @@ function useScreenSync(scope: InvestmentScreen, resources: ScreenResource[]) {
 			}
 
 			deniedRef.current.add(status.error);
-			if (apiErrorCode(status.error) !== "NOT_FOUND")
+			if (!isApiErrorCode(apiErrorCode(status.error), ApiErrorCode.NotFound))
 				invalidateResourceAccess(client, "brokerage", status.error);
 		}
 		const latest = new Map<string, ResourceMeta>();

src/features/tbank-connection/ui/TbankConnectionSection/TbankConnectionSectionLoaded.tsx

@@ -13,13 +13,15 @@ import { useEffect, useRef, useState } from "react";
 import { useForm } from "react-hook-form";
 import { useTranslation } from "react-i18next";
 
-import { apiErrorCode, apiQueryClient } from "@/shared/api";
+import { ApiErrorCode, apiErrorCode, apiQueryClient, isApiErrorCode } from "@/shared/api";
 
 import {
 	commitTbankConnectionBoundary,
 	type TbankConnectionStatus,
 } from "../../model/connection-boundary";
 
+enum ConnectionErrorCode { RequestFailed = "REQUEST_ERROR" }
+
 type TbankConnectionSectionLoadedProps = {
 	refreshError: boolean;
 	refreshing: boolean;
@@ -43,7 +45,7 @@ const TbankConnectionSectionLoaded: FC<TbankConnectionSectionLoadedProps> = (
 		reset,
 	} = useForm<{ token: string }>();
 	const update = apiQueryClient.useMutation("put", "/api/v1/tbank-connection", {
-		onError: error => setRequestError(apiErrorCode(error) ?? "REQUEST_ERROR"),
+		onError: error => setRequestError(apiErrorCode(error) ?? ConnectionErrorCode.RequestFailed),
 		onSuccess: (data) => {
 			commitTbankConnectionBoundary(queryClient, data);
 			reset();
@@ -62,7 +64,7 @@ const TbankConnectionSectionLoaded: FC<TbankConnectionSectionLoadedProps> = (
 			},
 		},
 	);
-	const unavailableMessage = requestError === "TBANK_UNAVAILABLE" ? "tbank.unavailable" : "tbank.requestError";
+	const unavailableMessage = isApiErrorCode(requestError, ApiErrorCode.TbankUnavailable) ? "tbank.unavailable" : "tbank.requestError";
 	const isPending = update.isPending || remove.isPending;
 	const isConnected = status.connected;
 	useEffect(() => {
@@ -119,7 +121,7 @@ const TbankConnectionSectionLoaded: FC<TbankConnectionSectionLoadedProps> = (
 						{requestError && (
 							<Alert color="red">
 								{t(
-									requestError === "INVALID_TBANK_TOKEN"
+									isApiErrorCode(requestError, ApiErrorCode.InvalidTbankToken)
 										? "tbank.invalidToken"
 										: unavailableMessage,
 								)}

src/pages/account-operations/ui/AccountOperationsPage/AccountOperationsPage.vm.ts

@@ -11,7 +11,7 @@ import {
 	useBrokerageOperations,
 } from "@/entities/broker-operation";
 import { useScreenSync } from "@/features/tbank-connection";
-import { apiErrorCode } from "@/shared/api";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "@/shared/api";
 
 type AccountOperationsPageViewModel
 	= | {
@@ -114,7 +114,7 @@ const useAccountOperationsPageVm = (
 
 	const resetCursors = () => setPagination({ cursors: [], scopeKey });
 	const retry = () => {
-		if (apiErrorCode(operations.error) === "INVALID_OPERATIONS_CURSOR") {
+		if (isApiErrorCode(apiErrorCode(operations.error), ApiErrorCode.InvalidOperationsCursor)) {
 			void queryClient.invalidateQueries({
 				exact: true,
 				queryKey: brokerageOperationsQueryOptions(accountId, firstPageQuery)
@@ -136,7 +136,7 @@ const useAccountOperationsPageVm = (
 	if (
 		(operations.isError || operations.meta?.sync.state === "failed")
 		&& (!operations.data
-			|| apiErrorCode(operations.error) === "INVALID_OPERATIONS_CURSOR")
+			|| isApiErrorCode(apiErrorCode(operations.error), ApiErrorCode.InvalidOperationsCursor))
 	)
 		return { onReset, retry, state: "error" };
 	if (!operations.data) return { state: "loading" };

src/pages/account/ui/AccountPage/components/AccountPageError.view.tsx

@@ -5,12 +5,14 @@ import { StateView } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
+
 type AccountPageErrorProps = { code?: string; retry: () => void };
 
 const AccountPageError: FC<AccountPageErrorProps> = (props) => {
 	const { code, retry } = props;
 	const { t } = useTranslation();
-	if (code === "NOT_FOUND")
+	if (isApiErrorCode(code, ApiErrorCode.NotFound))
 		return (
 			<StateView
 				action={(
@@ -23,7 +25,7 @@ const AccountPageError: FC<AccountPageErrorProps> = (props) => {
 				title={t("portfolio.accountUnavailableTitle")}
 			/>
 		);
-	if (code === "TBANK_NOT_CONNECTED" || code === "INVALID_TBANK_TOKEN")
+	if (isApiErrorCode(code, ApiErrorCode.TbankNotConnected) || isApiErrorCode(code, ApiErrorCode.InvalidTbankToken))
 		return (
 			<StateView
 				action={(
@@ -36,7 +38,7 @@ const AccountPageError: FC<AccountPageErrorProps> = (props) => {
 				title={t("portfolio.connectionErrorTitle")}
 			/>
 		);
-	if (code === "TBANK_UNAVAILABLE")
+	if (isApiErrorCode(code, ApiErrorCode.TbankUnavailable))
 		return (
 			<StateView
 				action={<Button onClick={retry}>{t("accounts.retry")}</Button>}

src/pages/accounts/ui/AccountsPage/components/AccountsPageError.view.tsx

@@ -5,6 +5,8 @@ import { StateView } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
+
 type AccountsPageErrorProps = { code?: string; retry?: () => void };
 
 const AccountsPageError: FC<AccountsPageErrorProps> = (props) => {
@@ -15,7 +17,7 @@ const AccountsPageError: FC<AccountsPageErrorProps> = (props) => {
 			{t("accounts.openSettings")}
 		</Button>
 	);
-	if (code === "TBANK_NOT_CONNECTED")
+	if (isApiErrorCode(code, ApiErrorCode.TbankNotConnected))
 		return (
 			<StateView
 				action={settingsAction}
@@ -24,7 +26,7 @@ const AccountsPageError: FC<AccountsPageErrorProps> = (props) => {
 				title={t("accounts.notConnectedTitle")}
 			/>
 		);
-	if (code === "INVALID_TBANK_TOKEN")
+	if (isApiErrorCode(code, ApiErrorCode.InvalidTbankToken))
 		return (
 			<StateView
 				action={settingsAction}
@@ -33,7 +35,7 @@ const AccountsPageError: FC<AccountsPageErrorProps> = (props) => {
 				title={t("accounts.invalidTokenTitle")}
 			/>
 		);
-	if (code === "TBANK_UNAVAILABLE")
+	if (isApiErrorCode(code, ApiErrorCode.TbankUnavailable))
 		return (
 			<StateView
 				action={(

src/pages/bond/ui/BondPage/BondPage.tsx

@@ -5,6 +5,8 @@ import { LoadingSkeleton } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link, Navigate } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
+
 import { BondPageView } from "./BondPage.view";
 import { useBondPageVm } from "./BondPage.vm";
 
@@ -22,15 +24,15 @@ const BondPage: FC = () => {
 				</Stack>
 			</LoadingSkeleton>
 		);
-	const unavailableMessage = vm.code === "BOND_TICKER_AMBIGUOUS" ? "bond.ambiguousTicker" : "bond.unavailableText";
+	const unavailableMessage = isApiErrorCode(vm.code, ApiErrorCode.BondTickerAmbiguous) ? "bond.ambiguousTicker" : "bond.unavailableText";
 	if (!vm.bond)
 		return (
 			<Stack role="alert">
 				<Title order={1}>{t("bond.unavailable")}</Title>
 				<Text>
 					{t(
-						vm.code === "TBANK_NOT_CONNECTED"
-						|| vm.code === "INVALID_TBANK_TOKEN"
+						isApiErrorCode(vm.code, ApiErrorCode.TbankNotConnected)
+						|| isApiErrorCode(vm.code, ApiErrorCode.InvalidTbankToken)
 							? "bond.connect"
 							: unavailableMessage,
 					)}

src/pages/bonds/ui/BondsPage/BondsPage.view.tsx

@@ -18,6 +18,7 @@ import { LoadingSkeleton } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
 import {
 	formatDate,
 	formatDecimal,
@@ -188,8 +189,8 @@ const BondsPageView: FC<BondsPageViewProps> = (props) => {
 					<Stack gap="xs">
 						<Text>
 							{t(
-								vm.code === "TBANK_NOT_CONNECTED"
-								|| vm.code === "INVALID_TBANK_TOKEN"
+								isApiErrorCode(vm.code, ApiErrorCode.TbankNotConnected)
+								|| isApiErrorCode(vm.code, ApiErrorCode.InvalidTbankToken)
 									? "bond.connect"
 									: "stock.sectionError",
 							)}

src/pages/card/ui/CardPage/CardPage.vm.ts

@@ -11,7 +11,7 @@ import {
 	useBankOperations,
 	useBankSummary,
 } from "@/entities/bank-card";
-import { apiErrorCode } from "@/shared/api";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "@/shared/api";
 import { formatDate, formatMoney } from "@/shared/lib";
 
 const PAGE_SIZES = new Set(["5", "10", "20", "50", "100", "all"]);
@@ -81,7 +81,7 @@ function useCardPageVm() {
 		deleting,
 		editingCard,
 		history,
-		notFound: apiErrorCode(card.error) === "BANK_NOT_FOUND",
+		notFound: isApiErrorCode(apiErrorCode(card.error), ApiErrorCode.BankNotFound),
 		operation,
 		page,
 		pageSize,

src/pages/card/ui/OperationForm/OperationForm.vm.ts

@@ -27,6 +27,9 @@ import type {
 	OperationValues,
 } from "./OperationForm.types";
 
+// ZodIssueCode is deprecated; this is the custom refinement code accepted by Zod.
+enum FormIssueCode { Custom = "custom" }
+
 const MAX_DESCRIPTION_LENGTH = 500;
 
 const operationSchema = z.object({
@@ -49,13 +52,13 @@ function validateRefund(values: OperationValues, context: z.RefinementCtx,
 	expense: BankOperation | undefined, limit: BankOperation["availableRefund"] | undefined) {
 	if (!expense || expense.cardId !== values.cardId)
 		context.addIssue({
-			code: "custom",
+			code: FormIssueCode.Custom,
 			path: ["originalExpenseId"],
 			...validationMessage("bank.validation.required")(undefined),
 		});
 	if (expense && values.date < expense.date)
 		context.addIssue({
-			code: "custom",
+			code: FormIssueCode.Custom,
 			path: ["date"],
 			...validationMessage("bank.validation.start")(undefined),
 		});
@@ -66,7 +69,7 @@ function validateRefund(values: OperationValues, context: z.RefinementCtx,
 		&& amount > (moneyCents(limit.value) ?? 0n)
 	)
 		context.addIssue({
-			code: "custom",
+			code: FormIssueCode.Custom,
 			path: ["amount"],
 			...validationMessage("bank.validation.refund")(undefined),
 		});
@@ -116,7 +119,7 @@ const useOperationFormVm = (props: OperationFormProps) => {
 				const target = props.cards.find(c => c.id === values.targetCardId);
 				if (!source || source.archivedAt)
 					context.addIssue({
-						code: "custom",
+						code: FormIssueCode.Custom,
 						path: ["cardId"],
 						...validationMessage("bank.validation.required")(undefined),
 					});
@@ -125,7 +128,7 @@ const useOperationFormVm = (props: OperationFormProps) => {
 					&& (!target || target.archivedAt || target.id === values.cardId)
 				)
 					context.addIssue({
-						code: "custom",
+						code: FormIssueCode.Custom,
 						path: ["targetCardId"],
 						...validationMessage("bank.validation.destination")(undefined),
 					});
@@ -136,7 +139,7 @@ const useOperationFormVm = (props: OperationFormProps) => {
 						&& values.date < target.openingDate)
 				)
 					context.addIssue({
-						code: "custom",
+						code: FormIssueCode.Custom,
 						path: ["date"],
 						...validationMessage("bank.validation.start")(undefined),
 					});
@@ -152,7 +155,7 @@ const useOperationFormVm = (props: OperationFormProps) => {
 					)
 				)
 					context.addIssue({
-						code: "custom",
+						code: FormIssueCode.Custom,
 						path: ["categoryId"],
 						...validationMessage("bank.validation.required")(undefined),
 					});

src/pages/stock/ui/StockPage/StockPage.tsx

@@ -5,6 +5,8 @@ import { LoadingSkeleton } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link, Navigate } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
+
 import { StockPageView } from "./StockPage.view";
 import { useStockPageVm } from "./StockPage.vm";
 
@@ -22,15 +24,15 @@ const StockPage: FC = () => {
 				</Stack>
 			</LoadingSkeleton>
 		);
-	const unavailableMessage = vm.code === "STOCK_TICKER_AMBIGUOUS" ? "stock.ambiguousTicker" : "stock.unavailableText";
+	const unavailableMessage = isApiErrorCode(vm.code, ApiErrorCode.StockTickerAmbiguous) ? "stock.ambiguousTicker" : "stock.unavailableText";
 	if (!vm.stock)
 		return (
 			<Stack role="alert">
 				<Title order={1}>{t("stock.unavailable")}</Title>
 				<Text>
 					{t(
-						vm.code === "TBANK_NOT_CONNECTED"
-						|| vm.code === "INVALID_TBANK_TOKEN"
+						isApiErrorCode(vm.code, ApiErrorCode.TbankNotConnected)
+						|| isApiErrorCode(vm.code, ApiErrorCode.InvalidTbankToken)
 							? "stock.connect"
 							: unavailableMessage,
 					)}

src/pages/stocks/ui/StocksPage/StocksPage.view.tsx

@@ -18,6 +18,7 @@ import { LoadingSkeleton } from "@wealthledger/ui";
 import { useTranslation } from "react-i18next";
 import { Link } from "react-router";
 
+import { ApiErrorCode, isApiErrorCode } from "@/shared/api";
 import { formatMoney, formatSnapshotTime } from "@/shared/lib";
 
 import type { StocksPageVm } from "./StocksPage.vm";
@@ -156,8 +157,8 @@ const StocksPageView: FC<StocksPageViewProps> = (props) => {
 					<Stack gap="xs">
 						<Text>
 							{t(
-								vm.code === "TBANK_NOT_CONNECTED"
-								|| vm.code === "INVALID_TBANK_TOKEN"
+								isApiErrorCode(vm.code, ApiErrorCode.TbankNotConnected)
+								|| isApiErrorCode(vm.code, ApiErrorCode.InvalidTbankToken)
 									? "stock.connect"
 									: "stock.sectionError",
 							)}

src/shared/api/client.ts

@@ -3,7 +3,7 @@ import createQueryClient from "openapi-react-query";
 
 import type { paths } from "./generated/schema";
 
-import { apiErrorCode } from "./problem-details";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "./problem-details";
 
 const HTTP_UNAUTHORIZED = 401;
 
@@ -101,7 +101,7 @@ async function fetchCurrent(
 	catch {
 		return response;
 	}
-	if (apiErrorCode(problem) !== "UNAUTHORIZED") return response;
+	if (!isApiErrorCode(apiErrorCode(problem), ApiErrorCode.Unauthorized)) return response;
 	if (!isCurrent()) throw new DOMException("Session changed", "AbortError");
 	if (!(await sessionState.handlers.refresh())) {
 		if (isCurrent()) sessionState.handlers.clear();

src/shared/api/index.ts

@@ -9,7 +9,7 @@ export {
 	invalidateApiRequests,
 } from "./client";
 export type { paths } from "./generated/schema";
-export { apiErrorCode } from "./problem-details";
+export { ApiErrorCode, apiErrorCode, isApiErrorCode } from "./problem-details";
 
 export {
 	invalidateResourceAccess,

src/shared/api/problem-details.test.ts

@@ -0,0 +1,13 @@
+import { expect, it } from "vitest";
+
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "./problem-details";
+
+it("matches known codes and preserves unknown wire codes for fallback handling", () => {
+	expect(isApiErrorCode(apiErrorCode({ code: "UNAUTHORIZED" }), ApiErrorCode.Unauthorized)).toBe(true);
+	const unknownCode = apiErrorCode({ code: "FUTURE_PROVIDER_ERROR" });
+	expect(unknownCode).toBe("FUTURE_PROVIDER_ERROR");
+	expect(isApiErrorCode(unknownCode, ApiErrorCode.Unauthorized)).toBe(false);
+	expect(isApiErrorCode(undefined, ApiErrorCode.Unauthorized)).toBe(false);
+	expect(apiErrorCode(null)).toBeUndefined();
+	expect(apiErrorCode({})).toBeUndefined();
+});

src/shared/api/problem-details.ts

@@ -1,7 +1,30 @@
+enum ApiErrorCode {
+	BankDependentRefunds = "BANK_DEPENDENT_REFUNDS",
+	BankIntentConflict = "BANK_INTENT_CONFLICT",
+	BankNotFound = "BANK_NOT_FOUND",
+	BankRefundLimit = "BANK_REFUND_LIMIT",
+	BankVersionConflict = "BANK_VERSION_CONFLICT",
+	BankWriteConflict = "BANK_WRITE_CONFLICT",
+	BondTickerAmbiguous = "BOND_TICKER_AMBIGUOUS",
+	Forbidden = "FORBIDDEN",
+	InvalidOperationsCursor = "INVALID_OPERATIONS_CURSOR",
+	InvalidTbankToken = "INVALID_TBANK_TOKEN",
+	NotFound = "NOT_FOUND",
+	StockTickerAmbiguous = "STOCK_TICKER_AMBIGUOUS",
+	TbankNotConnected = "TBANK_NOT_CONNECTED",
+	TbankUnavailable = "TBANK_UNAVAILABLE",
+	Unauthorized = "UNAUTHORIZED",
+}
+
 function apiErrorCode(error: unknown): string | undefined {
 	return typeof error === "object" && error !== null && "code" in error
 		? String(error.code)
 		: undefined;
 }
 
-export { apiErrorCode };
+// Incoming codes are an open wire string; unknown values retain their fallback.
+function isApiErrorCode(value: unknown, expected: ApiErrorCode): boolean {
+	return value === expected;
+}
+
+export { ApiErrorCode, apiErrorCode, isApiErrorCode };

src/shared/api/resource-query.ts

@@ -10,7 +10,7 @@ import type { components } from "./generated/schema";
 
 import { useAuthenticatedQuery } from "./authenticated-query";
 import { getAuthenticatedSessionSnapshot } from "./client";
-import { apiErrorCode } from "./problem-details";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "./problem-details";
 
 const accessEpochs = new WeakMap<QueryClient, Map<string, number>>();
 
@@ -23,13 +23,14 @@ function invalidateResourceAccess(
 	group: string,
 	error: unknown,
 ) {
+	const errorCode = apiErrorCode(error);
 	if (
-		![
-			"FORBIDDEN",
-			"INVALID_TBANK_TOKEN",
-			"NOT_FOUND",
-			"TBANK_NOT_CONNECTED",
-		].includes(apiErrorCode(error) ?? "")
+		[
+			ApiErrorCode.Forbidden,
+			ApiErrorCode.InvalidTbankToken,
+			ApiErrorCode.NotFound,
+			ApiErrorCode.TbankNotConnected,
+		].every(code => !isApiErrorCode(errorCode, code))
 	)
 		return;
 	const epochs = accessEpochs.get(client) ?? new Map<string, number>();

tsconfig.app.json

@@ -21,7 +21,6 @@
 		"jsx": "react-jsx",
 		"noUnusedLocals": true,
 		"noUnusedParameters": true,
-		"erasableSyntaxOnly": true,
 		"noFallthroughCasesInSwitch": true
 	},
 	"include": ["src", ".storybook/preview.tsx", "packages/*/src"]