diff --git a/PLAN.md b/PLAN.md
index afd6114..bf7c203 100644
--- a/PLAN.md
+++ b/PLAN.md
@@ -635,9 +635,13 @@ impl) + the VK bridge (`vkRewardedReady` / `vkShowRewarded`), the backend `Credi
 order-less, idempotent on a client nonce, floored by the caps, payout from config
 `rewarded_payout_chips` default 0 = off), the `wallet.reward` edge op returning the updated wallet
 (with `reward_chips` gating the "watch for chips" CTA), and a **contour test stub** (`VITE_ADS_STUB` →
-a toast instead of a real ad; prod always real). A temporary diagnostic logs the raw VK `data` so we
-confirm on the contour exactly what VK returns (harden to signature-verify if it carries one). The
-legacy `paid_account` / `hint_balance` drop (D31) and the **interstitial** are the next slice.
+a toast instead of a real ad; prod always real). A temporary diagnostic confirmed on the contour that
+VK returns **only `{result:true}`** (no token/signature) — client-attested is final, no hardening
+possible; the diagnostic is removed. The slice also **corrects the VK-iOS freeze to purchase-only**
+(rewarded on VK-iOS earns chips, which the old blanket "spend freeze" then blocked from spending —
+Apple forbids only *buying* in-app values, not spending or earning them; `vkFrozen()` now gates only
+`CreateOrder`, not `spendableSources`, so VK-wallet chips spend on VK-iOS). The legacy `paid_account`
+/ `hint_balance` drop (D31) and the **interstitial** are the next slice.
 
 **Goal.** VK video ads: the post-move interstitial (frequency-gated) and the rewarded video
 (credits chips via server verify), plus extending the existing banner suppression to
diff --git a/backend/internal/payments/gate.go b/backend/internal/payments/gate.go
index a136536..a3965a0 100644
--- a/backend/internal/payments/gate.go
+++ b/backend/internal/payments/gate.go
@@ -89,8 +89,10 @@ func NewContext(kind, subtype string) Context {
 // every spend/purchase and the application of any foreign origin.
 func (c Context) Trusted() bool { return c.Kind.Valid() }
 
-// vkFrozen reports whether this is the VK-iOS spend freeze: VK context on the trusted iOS
-// subtype. A previously bought benefit still applies there, but no spend or purchase is possible.
+// vkFrozen reports whether this is the VK-iOS purchase freeze: VK context on the trusted iOS
+// subtype. Apple's ToS forbids only BUYING in-app values there, so a purchase (money -> chips) is
+// refused; earning chips (rewarded ads) and SPENDING chips already in the VK wallet — earned or
+// bought on the same account elsewhere (e.g. VK Android) — are legal and stay allowed.
 func (c Context) vkFrozen() bool { return c.Kind == SourceVK && c.Subtype == SubtypeIOS }
 
 // spendPriority is the fixed draw order when several segments are spendable in one context
@@ -103,11 +105,12 @@ func has(present []Source, s Source) bool {
 }
 
 // spendableSources returns the chip segments that may be SPENT in the context, in draw-priority
-// order, restricted to the sources the account actually has (present). It is empty when the
-// platform is untrusted (fail-closed) or VK-iOS (frozen): inside VK/TG only the same-named
-// segment is spendable; on web/native all attached segments are, drained direct→vk→tg.
+// order, restricted to the sources the account actually has (present). It is empty only when the
+// platform is untrusted (fail-closed); VK-iOS is NOT excluded — the freeze is purchase-only, so
+// spending VK-wallet chips there is allowed. Inside VK/TG only the same-named segment is spendable;
+// on web/native all attached segments are, drained direct→vk→tg.
 func spendableSources(c Context, present []Source) []Source {
-	if !c.Trusted() || c.vkFrozen() {
+	if !c.Trusted() {
 		return nil
 	}
 	switch c.Kind {
@@ -128,10 +131,10 @@ func spendableSources(c Context, present []Source) []Source {
 }
 
 // applicableOrigins returns the benefit origins that APPLY in the context, in draw-priority
-// order, restricted to present sources. It differs from spendableSources in one way: VK-iOS is
-// NOT excluded — a benefit bought earlier still applies while spending is frozen. Inside VK/TG
-// only the same-named origin applies (a foreign, e.g. direct, origin never activates inside a
-// store — the compliance wall); on web/native direct+vk+tg all apply, drained direct→vk→tg.
+// order, restricted to present sources. It mirrors spendableSources (both gate only on a trusted
+// platform now that the VK-iOS freeze is purchase-only). Inside VK/TG only the same-named origin
+// applies (a foreign, e.g. direct, origin never activates inside a store — the compliance wall);
+// on web/native direct+vk+tg all apply, drained direct→vk→tg.
 func applicableOrigins(c Context, present []Source) []Source {
 	if !c.Trusted() {
 		return nil
diff --git a/backend/internal/payments/gate_test.go b/backend/internal/payments/gate_test.go
index 304276b..1899469 100644
--- a/backend/internal/payments/gate_test.go
+++ b/backend/internal/payments/gate_test.go
@@ -16,7 +16,8 @@ func TestSpendableSources(t *testing.T) {
 		want    []Source
 	}{
 		{"vk android, vk present", Context{Kind: SourceVK, Subtype: "android"}, allPresent, []Source{SourceVK}},
-		{"vk ios frozen", Context{Kind: SourceVK, Subtype: SubtypeIOS}, allPresent, nil},
+		// VK-iOS spends its own vk segment: the freeze is purchase-only, spending is allowed.
+		{"vk ios spends vk", Context{Kind: SourceVK, Subtype: SubtypeIOS}, allPresent, []Source{SourceVK}},
 		{"vk android, vk absent", Context{Kind: SourceVK, Subtype: "android"}, []Source{SourceDirect}, nil},
 		{"telegram", Context{Kind: SourceTelegram, Subtype: "web"}, allPresent, []Source{SourceTelegram}},
 		{"telegram, tg absent", Context{Kind: SourceTelegram}, []Source{SourceVK}, nil},
@@ -41,8 +42,8 @@ func TestApplicableOrigins(t *testing.T) {
 		present []Source
 		want    []Source
 	}{
-		// A benefit still APPLIES on VK-iOS while spending is frozen.
-		{"vk ios still applies", Context{Kind: SourceVK, Subtype: SubtypeIOS}, allPresent, []Source{SourceVK}},
+		// A vk-origin benefit applies on VK-iOS (spending is allowed there — the freeze is purchase-only).
+		{"vk ios applies", Context{Kind: SourceVK, Subtype: SubtypeIOS}, allPresent, []Source{SourceVK}},
 		{"vk android", Context{Kind: SourceVK, Subtype: "android"}, allPresent, []Source{SourceVK}},
 		{"telegram", Context{Kind: SourceTelegram}, allPresent, []Source{SourceTelegram}},
 		{"direct all, priority", Context{Kind: SourceDirect}, allPresent, []Source{SourceDirect, SourceVK, SourceTelegram}},
diff --git a/backend/internal/payments/service_intake_test.go b/backend/internal/payments/service_intake_test.go
index 11159b1..a1252a6 100644
--- a/backend/internal/payments/service_intake_test.go
+++ b/backend/internal/payments/service_intake_test.go
@@ -28,7 +28,7 @@ func TestCreateOrderGateRejections(t *testing.T) {
 		cxt  Context
 	}{
 		{"untrusted context", Context{}},
-		{"vk-ios spend freeze", Context{Kind: SourceVK, Subtype: SubtypeIOS}},
+		{"vk-ios purchase freeze", Context{Kind: SourceVK, Subtype: SubtypeIOS}},
 		{"method segment not attached", Context{Kind: SourceTelegram}},
 	}
 	for _, tc := range cases {
diff --git a/backend/internal/payments/wallet_test.go b/backend/internal/payments/wallet_test.go
index 8fc9aaf..e0e7150 100644
--- a/backend/internal/payments/wallet_test.go
+++ b/backend/internal/payments/wallet_test.go
@@ -102,10 +102,11 @@ func TestWalletSegments(t *testing.T) {
 	if len(got.Segments) != 1 || got.Segments[0].Source != SourceVK || !got.Segments[0].Spendable {
 		t.Errorf("vk-android wallet = %+v", got.Segments)
 	}
-	// VK iOS: only vk shown, frozen (not spendable) but the balance is visible.
+	// VK iOS: only vk shown, and spendable — the freeze is purchase-only, so VK-wallet chips still
+	// spend there (only buying more chips for money is blocked).
 	got, _ = svc.Wallet(context.Background(), id, NewContext("vk", "ios"), present)
-	if len(got.Segments) != 1 || got.Segments[0].Chips != 50 || got.Segments[0].Spendable {
-		t.Errorf("vk-ios wallet = %+v (want vk 50 frozen)", got.Segments)
+	if len(got.Segments) != 1 || got.Segments[0].Chips != 50 || !got.Segments[0].Spendable {
+		t.Errorf("vk-ios wallet = %+v (want vk 50 spendable)", got.Segments)
 	}
 }
 
diff --git a/backend/internal/server/handlers_wallet.go b/backend/internal/server/handlers_wallet.go
index 0f4ba9e..89f68e7 100644
--- a/backend/internal/server/handlers_wallet.go
+++ b/backend/internal/server/handlers_wallet.go
@@ -175,12 +175,10 @@ func (s *Server) handleWalletBuy(c *gin.Context) {
 	c.JSON(http.StatusOK, walletDTOFrom(view))
 }
 
-// walletRewardRequest is the POST body of a rewarded-video credit: a client nonce (the idempotency
-// key for a single watched view — a retry credits once) and Diag, the raw VK ad result forwarded for
-// a temporary diagnostic log while we confirm exactly what VK returns on the contour.
+// walletRewardRequest is the POST body of a rewarded-video credit: a client nonce, the idempotency
+// key for a single watched view (a retry credits once).
 type walletRewardRequest struct {
 	Nonce string `json:"nonce"`
-	Diag  string `json:"diag"`
 }
 
 // handleWalletReward credits a rewarded-video view's chips to the VK segment, client-attested and
@@ -203,15 +201,6 @@ func (s *Server) handleWalletReward(c *gin.Context) {
 		s.abortErr(c, err)
 		return
 	}
-	// Temporary diagnostic: log the raw VK ad result (bounded — untrusted client input) to learn its
-	// exact shape on the contour; if it carries a verifiable token we harden past client-attested.
-	if req.Diag != "" {
-		diag := req.Diag
-		if len(diag) > 2000 {
-			diag = diag[:2000]
-		}
-		s.log.Info("rewarded ad diagnostic", zap.String("account", uid.String()), zap.String("vk_data", diag))
-	}
 	outcome, err := s.payments.CreditReward(ctx, uid, cxt, present, req.Nonce)
 	if err != nil {
 		s.abortErr(c, err)
diff --git a/docs/PAYMENTS.md b/docs/PAYMENTS.md
index 572e5dd..222e08d 100644
--- a/docs/PAYMENTS.md
+++ b/docs/PAYMENTS.md
@@ -82,7 +82,7 @@ leaking out to the open web) is allowed.
 | Execution context   | Spendable chip segments | Spend priority     |
 |---------------------|-------------------------|--------------------|
 | Inside VK (Android) | `vk`                    | —                  |
-| Inside VK (iOS)     | none — frozen (view only)| —                 |
+| Inside VK (iOS)     | `vk` (purchase-frozen)  | —                  |
 | Inside Telegram     | `telegram`              | —                  |
 | Web / native (Direct)| `direct` + `vk` + `telegram` | direct → vk → tg |
 
@@ -90,9 +90,11 @@ leaking out to the open web) is allowed.
   invisible-as-spendable there.
 - On the web the store has no jurisdiction, so all attached segments are spendable, drained
   by priority direct → vk → tg.
-- **VK iOS** is frozen for spending (Apple forbids spending virtual currency on digital
-  goods outside IAP inside VK on iOS): the balance is shown as a number, but no purchase or
-  spend is possible. A previously bought benefit still *applies* there.
+- **VK iOS is a PURCHASE freeze, not a spend freeze.** Apple's ToS forbids only **buying** in-app
+  values there (for any currency) — so a purchase (money → chips) is refused. **Spending** VK-wallet
+  chips (earned via rewarded ads or bought on the same VK account elsewhere, e.g. VK Android) and
+  earning them are legal and stay allowed on VK iOS; a bought benefit also *applies* there. Only the
+  money-in step is blocked.
 
 The account is **single** (identities merge, one profile/friends/stats). The gate is
 **logical**: in a VK/TG context the server activates only the same-named segment. It rests
diff --git a/docs/PAYMENTS_DECISIONS_ru.md b/docs/PAYMENTS_DECISIONS_ru.md
index 4fa0775..c808915 100644
--- a/docs/PAYMENTS_DECISIONS_ru.md
+++ b/docs/PAYMENTS_DECISIONS_ru.md
@@ -110,6 +110,11 @@ web+PWA / native Android+iOS через Capacitor). Владелец (самоз
   сессии. Платформа несёт **kind** (vk/tg/direct) **+ подтип** (ios/android/web) —
   подтип обязателен (VK iOS заморожен). TG `initData`-валидатор уже есть
   (`platform/telegram/internal/initdata`).
+  **АМЕНД (E6, находка владельца по ToS):** VK iOS — **заморозка только ПОКУПОК** (деньги→Фишки),
+  а не траты. Apple запрещает там лишь **покупать** внутриигровые ценности за любую валюту; а
+  **тратить** Фишки VK-кошелька (заработанные rewarded-рекламой или купленные на том же VK-аккаунте
+  в Android) и зарабатывать их — легально и на iOS. Код: `vkFrozen()` гейтит только `CreateOrder`
+  (покупку), не `spendableSources` (трату).
 - **D18. Fail-closed:** недоверенная/неподтверждённая платформа (VK/TG-сессия без
   валидной подписи на старте; старая сессия без записанной платформы) → запрет
   трат/покупок/применения чужого origin, только просмотр.
diff --git a/docs/PAYMENTS_ru.md b/docs/PAYMENTS_ru.md
index 897a960..f7c73ee 100644
--- a/docs/PAYMENTS_ru.md
+++ b/docs/PAYMENTS_ru.md
@@ -83,7 +83,7 @@
 | Контекст исполнения  | Тратимые сегменты Фишек   | Приоритет траты    |
 |----------------------|---------------------------|--------------------|
 | Внутри VK (Android)  | `vk`                      | —                  |
-| Внутри VK (iOS)      | нет — заморожено (только просмотр) | —          |
+| Внутри VK (iOS)      | `vk` (заморожена покупка) | —                  |
 | Внутри Telegram      | `telegram`                | —                  |
 | Web / native (Direct)| `direct` + `vk` + `telegram` | direct → vk → tg |
 
@@ -91,9 +91,11 @@
   `direct`) там невидимо как тратимое.
 - В вебе у стора нет юрисдикции, поэтому доступны все привязанные сегменты, списываются по
   приоритету direct → vk → tg.
-- **VK iOS** заморожен для траты (Apple запрещает тратить виртуальную валюту на цифровые
-  товары мимо IAP внутри VK на iOS): баланс показывается числом, но покупка/трата
-  невозможны. Ранее купленный бенефит там всё равно *действует*.
+- **VK iOS — заморозка ПОКУПОК, а не траты.** ToS Apple запрещает там только **покупать**
+  внутриигровые ценности (за любую валюту) — поэтому покупка (деньги → Фишки) отклоняется. А
+  **тратить** Фишки VK-кошелька (заработанные рекламой или купленные на том же VK-аккаунте, напр. в
+  VK Android) и зарабатывать их — легально и на VK iOS разрешено; купленный бенефит там тоже
+  *действует*. Блокируется только шаг «деньги внутрь».
 
 Аккаунт **единый** (привязки сливаются, один профиль/друзья/статистика). Гейт
 **логический**: в контексте VK/TG сервер активирует только одноимённый сегмент. Держится на
diff --git a/gateway/internal/backendclient/api.go b/gateway/internal/backendclient/api.go
index 3c2287c..28b929b 100644
--- a/gateway/internal/backendclient/api.go
+++ b/gateway/internal/backendclient/api.go
@@ -384,18 +384,16 @@ type walletBuyBody struct {
 	ProductID string `json:"product_id"`
 }
 
-// walletRewardBody is the rewarded-video credit request: the per-view idempotency nonce and the raw
-// VK ad result forwarded for the temporary contour diagnostic.
+// walletRewardBody is the rewarded-video credit request: the per-view idempotency nonce.
 type walletRewardBody struct {
 	Nonce string `json:"nonce"`
-	Diag  string `json:"diag"`
 }
 
 // WalletReward credits a watched rewarded video and returns the updated wallet (client-attested + a
-// backend daily cap). A reached cap or unconfigured payout surfaces as an APIError domain code.
-func (c *Client) WalletReward(ctx context.Context, userID, nonce, diag string) (WalletResp, error) {
+// backend daily/hourly cap). A reached cap or unconfigured payout surfaces as an APIError domain code.
+func (c *Client) WalletReward(ctx context.Context, userID, nonce string) (WalletResp, error) {
 	var out WalletResp
-	err := c.do(ctx, http.MethodPost, "/api/v1/user/wallet/reward", userID, "", walletRewardBody{Nonce: nonce, Diag: diag}, &out)
+	err := c.do(ctx, http.MethodPost, "/api/v1/user/wallet/reward", userID, "", walletRewardBody{Nonce: nonce}, &out)
 	return out, err
 }
 
diff --git a/gateway/internal/transcode/transcode.go b/gateway/internal/transcode/transcode.go
index 0e3903d..e3c60e4 100644
--- a/gateway/internal/transcode/transcode.go
+++ b/gateway/internal/transcode/transcode.go
@@ -382,11 +382,11 @@ func walletOrderHandler(backend *backendclient.Client, minter InvoiceMinter) Han
 }
 
 // walletRewardHandler credits a watched rewarded video and returns the updated wallet. The nonce is
-// the client's per-view idempotency key; diag carries the raw VK ad result for the contour diagnostic.
+// the client's per-view idempotency key.
 func walletRewardHandler(backend *backendclient.Client) Handler {
 	return func(ctx context.Context, req Request) ([]byte, error) {
 		in := fb.GetRootAsWalletRewardRequest(req.Payload, 0)
-		w, err := backend.WalletReward(ctx, req.UserID, string(in.Nonce()), string(in.Diag()))
+		w, err := backend.WalletReward(ctx, req.UserID, string(in.Nonce()))
 		if err != nil {
 			return nil, err
 		}
diff --git a/pkg/fbs/scrabble.fbs b/pkg/fbs/scrabble.fbs
index c8f458b..124cfb8 100644
--- a/pkg/fbs/scrabble.fbs
+++ b/pkg/fbs/scrabble.fbs
@@ -877,10 +877,9 @@ table WalletBuyRequest {
 }
 
 // WalletRewardRequest credits a watched rewarded video: nonce is the per-view idempotency key (a
-// retry credits once); diag carries the raw VK ad result for a temporary contour diagnostic log.
+// retry credits once).
 table WalletRewardRequest {
   nonce:string;
-  diag:string;
 }
 
 // WalletOrderRequest opens a money order to fund a chip pack: the pack to buy.
diff --git a/pkg/fbs/scrabblefb/WalletRewardRequest.go b/pkg/fbs/scrabblefb/WalletRewardRequest.go
index 32c2a8e..2694dde 100644
--- a/pkg/fbs/scrabblefb/WalletRewardRequest.go
+++ b/pkg/fbs/scrabblefb/WalletRewardRequest.go
@@ -49,23 +49,12 @@ func (rcv *WalletRewardRequest) Nonce() []byte {
 	return nil
 }
 
-func (rcv *WalletRewardRequest) Diag() []byte {
-	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
-	if o != 0 {
-		return rcv._tab.ByteVector(o + rcv._tab.Pos)
-	}
-	return nil
-}
-
 func WalletRewardRequestStart(builder *flatbuffers.Builder) {
-	builder.StartObject(2)
+	builder.StartObject(1)
 }
 func WalletRewardRequestAddNonce(builder *flatbuffers.Builder, nonce flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(nonce), 0)
 }
-func WalletRewardRequestAddDiag(builder *flatbuffers.Builder, diag flatbuffers.UOffsetT) {
-	builder.PrependUOffsetTSlot(1, flatbuffers.UOffsetT(diag), 0)
-}
 func WalletRewardRequestEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
 	return builder.EndObject()
 }
diff --git a/ui/src/gen/fbs/scrabblefb/wallet-reward-request.ts b/ui/src/gen/fbs/scrabblefb/wallet-reward-request.ts
index 4e1d9cf..5353be7 100644
--- a/ui/src/gen/fbs/scrabblefb/wallet-reward-request.ts
+++ b/ui/src/gen/fbs/scrabblefb/wallet-reward-request.ts
@@ -27,34 +27,22 @@ nonce(optionalEncoding?:any):string|Uint8Array|null {
   return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
 }
 
-diag():string|null
-diag(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
-diag(optionalEncoding?:any):string|Uint8Array|null {
-  const offset = this.bb!.__offset(this.bb_pos, 6);
-  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
-}
-
 static startWalletRewardRequest(builder:flatbuffers.Builder) {
-  builder.startObject(2);
+  builder.startObject(1);
 }
 
 static addNonce(builder:flatbuffers.Builder, nonceOffset:flatbuffers.Offset) {
   builder.addFieldOffset(0, nonceOffset, 0);
 }
 
-static addDiag(builder:flatbuffers.Builder, diagOffset:flatbuffers.Offset) {
-  builder.addFieldOffset(1, diagOffset, 0);
-}
-
 static endWalletRewardRequest(builder:flatbuffers.Builder):flatbuffers.Offset {
   const offset = builder.endObject();
   return offset;
 }
 
-static createWalletRewardRequest(builder:flatbuffers.Builder, nonceOffset:flatbuffers.Offset, diagOffset:flatbuffers.Offset):flatbuffers.Offset {
+static createWalletRewardRequest(builder:flatbuffers.Builder, nonceOffset:flatbuffers.Offset):flatbuffers.Offset {
   WalletRewardRequest.startWalletRewardRequest(builder);
   WalletRewardRequest.addNonce(builder, nonceOffset);
-  WalletRewardRequest.addDiag(builder, diagOffset);
   return WalletRewardRequest.endWalletRewardRequest(builder);
 }
 }
diff --git a/ui/src/lib/ads.ts b/ui/src/lib/ads.ts
index 573d76c..f68a442 100644
--- a/ui/src/lib/ads.ts
+++ b/ui/src/lib/ads.ts
@@ -17,12 +17,10 @@ export function adsStubEnabled(): boolean {
   return (import.meta.env as Record<string, string | undefined>).VITE_ADS_STUB === '1';
 }
 
-/** RewardedResult is one rewarded-ad view: whether it was watched, the raw provider result as JSON
- *  (forwarded for the contour diagnostic), and whether it was the test stub (so the caller can show
- *  the "ad fired" marker toast). */
+/** RewardedResult is one rewarded-ad view: whether it was watched, and whether it was the test stub
+ *  (so the caller can show the "ad fired" marker toast). */
 export interface RewardedResult {
   watched: boolean;
-  data: string;
   stub: boolean;
 }
 
@@ -44,8 +42,7 @@ export async function rewardedReady(): Promise<boolean> {
  */
 export async function showRewarded(): Promise<RewardedResult> {
   if (adsStubEnabled()) {
-    return { watched: true, data: JSON.stringify({ stub: true }), stub: true };
+    return { watched: true, stub: true };
   }
-  const r = await vkShowRewarded();
-  return { watched: r.watched, data: r.data, stub: false };
+  return { watched: await vkShowRewarded(), stub: false };
 }
diff --git a/ui/src/lib/client.ts b/ui/src/lib/client.ts
index c999a03..a79ba4c 100644
--- a/ui/src/lib/client.ts
+++ b/ui/src/lib/client.ts
@@ -152,9 +152,9 @@ export interface GatewayClient {
    *  client opens; chips are credited later, by the verified server callback. Direct rail only. */
   walletOrder(productId: string): Promise<WalletOrder>;
   /** walletReward credits a watched rewarded video (VK ads) and returns the updated wallet. nonce is
-   *  the per-view idempotency key; diag carries the raw VK ad result for the contour diagnostic.
-   *  Client-attested + a server daily/hourly cap; a reached cap rejects with a domain code. */
-  walletReward(nonce: string, diag: string): Promise<Wallet>;
+   *  the per-view idempotency key. Client-attested + a server daily/hourly cap; a reached cap rejects
+   *  with a domain code. */
+  walletReward(nonce: string): Promise<Wallet>;
 
   // --- friends ---
   friendsList(): Promise<AccountRef[]>;
diff --git a/ui/src/lib/codec.test.ts b/ui/src/lib/codec.test.ts
index 9dcc6e6..3bc24df 100644
--- a/ui/src/lib/codec.test.ts
+++ b/ui/src/lib/codec.test.ts
@@ -78,12 +78,11 @@ describe('codec', () => {
     expect(w.rewardChips).toBe(7);
   });
 
-  it('round-trips the wallet reward request (nonce + diag)', () => {
+  it('round-trips the wallet reward request (nonce)', () => {
     const req = fb.WalletRewardRequest.getRootAsWalletRewardRequest(
-      new ByteBuffer(encodeWalletReward('nonce-9', '{"result":true}')),
+      new ByteBuffer(encodeWalletReward('nonce-9')),
     );
     expect(req.nonce()).toBe('nonce-9');
-    expect(req.diag()).toBe('{"result":true}');
   });
 
   it('round-trips the wallet order request and response', () => {
diff --git a/ui/src/lib/codec.ts b/ui/src/lib/codec.ts
index 801e493..f229873 100644
--- a/ui/src/lib/codec.ts
+++ b/ui/src/lib/codec.ts
@@ -403,14 +403,12 @@ export function decodeWallet(buf: Uint8Array): Wallet {
 }
 
 // encodeWalletReward wraps a watched rewarded video for crediting (POST /user/wallet/reward): the
-// per-view idempotency nonce and the raw VK ad result forwarded for the contour diagnostic.
-export function encodeWalletReward(nonce: string, diag: string): Uint8Array {
+// per-view idempotency nonce.
+export function encodeWalletReward(nonce: string): Uint8Array {
   const b = new Builder(64);
   const n = b.createString(nonce);
-  const d = b.createString(diag);
   fb.WalletRewardRequest.startWalletRewardRequest(b);
   fb.WalletRewardRequest.addNonce(b, n);
-  fb.WalletRewardRequest.addDiag(b, d);
   return finish(b, fb.WalletRewardRequest.endWalletRewardRequest(b));
 }
 
diff --git a/ui/src/lib/mock/client.ts b/ui/src/lib/mock/client.ts
index 5622a7d..0e6363c 100644
--- a/ui/src/lib/mock/client.ts
+++ b/ui/src/lib/mock/client.ts
@@ -236,7 +236,7 @@ export class MockGateway implements GatewayClient {
     return { orderId: 'mock-order-' + productId, redirectUrl: 'https://mock.local/robokassa?order=' + productId };
   }
 
-  async walletReward(_nonce: string, _diag: string): Promise<Wallet> {
+  async walletReward(_nonce: string): Promise<Wallet> {
     // Mock rewarded credit: add the configured payout to the vk segment (no cap in the mock).
     const vk = this.mockWallet.segments.find((s) => s.source === 'vk');
     if (vk) vk.chips += this.mockWallet.rewardChips;
diff --git a/ui/src/lib/transport.ts b/ui/src/lib/transport.ts
index 9fe973b..2c066da 100644
--- a/ui/src/lib/transport.ts
+++ b/ui/src/lib/transport.ts
@@ -240,8 +240,8 @@ export function createTransport(baseUrl: string): GatewayClient {
     async walletOrder(productId: string) {
       return codec.decodeWalletOrder(await exec('wallet.order', codec.encodeWalletOrder(productId)));
     },
-    async walletReward(nonce: string, diag: string) {
-      return codec.decodeWallet(await exec('wallet.reward', codec.encodeWalletReward(nonce, diag)));
+    async walletReward(nonce: string) {
+      return codec.decodeWallet(await exec('wallet.reward', codec.encodeWalletReward(nonce)));
     },
 
     async friendsList() {
diff --git a/ui/src/lib/vk.ts b/ui/src/lib/vk.ts
index 6a0ab2f..bca6746 100644
--- a/ui/src/lib/vk.ts
+++ b/ui/src/lib/vk.ts
@@ -213,16 +213,15 @@ export async function vkRewardedReady(): Promise<boolean> {
 
 /**
  * vkShowRewarded shows a rewarded ad (VKWebAppShowNativeAds) and reports whether it was watched
- * (data.result) plus the full raw provider result as JSON — forwarded to the backend for the
- * temporary contour diagnostic (to confirm exactly what VK returns). A rejected call reports
- * not-watched with the error captured.
+ * (data.result — VK returns only this boolean, no server-verifiable token). A rejected call reports
+ * not-watched.
  */
-export async function vkShowRewarded(): Promise<{ watched: boolean; data: string }> {
+export async function vkShowRewarded(): Promise<boolean> {
   try {
     const data = await (await bridge()).send('VKWebAppShowNativeAds', { ad_format: 'reward' });
-    return { watched: !!(data as { result?: boolean }).result, data: JSON.stringify(data) };
-  } catch (e) {
-    return { watched: false, data: JSON.stringify({ error: String(e) }) };
+    return !!(data as { result?: boolean }).result;
+  } catch {
+    return false;
   }
 }
 
diff --git a/ui/src/screens/Wallet.svelte b/ui/src/screens/Wallet.svelte
index 57842bd..332b00a 100644
--- a/ui/src/screens/Wallet.svelte
+++ b/ui/src/screens/Wallet.svelte
@@ -63,7 +63,7 @@
       }
       const nonce = crypto.randomUUID();
       const before = wallet?.segments.find((s) => s.source === 'vk')?.chips ?? 0;
-      const w = await gateway.walletReward(nonce, res.data);
+      const w = await gateway.walletReward(nonce);
       wallet = w;
       const gained = (w.segments.find((s) => s.source === 'vk')?.chips ?? 0) - before;
       showToast(gained > 0 ? t('wallet.rewardCredited', { n: gained }) : t('wallet.rewardCredited', { n: w.rewardChips }));