feat(ads): VK post-move interstitial + retire deprecated hint_balance/paid_account

Interstitial video after a confirmed play or a hint, VK-only, offline
banner-only. The gate is client-mirrored: the backend puts the config
cooldowns (global 5m / vs_ai 30m / hint 1m) and a suppressed flag (the
no-ads / no_banner gate, same as the banner) on Profile.ads via adsFor;
the client self-gates on a per-kind last-shown time in localStorage, with
the VITE_ADS_STUB contour "ad fired" toast. Never fires after a pass,
exchange or resign. maybeShowInterstitial + vkShowInterstitial; the codec
and gateway transcode carry the ads block.

Also retires the deprecated accounts.hint_balance / paid_account domain
usage (expand-contract, code only — the columns stay for a later DROP so
image rollback stays DB-safe): drop the Account fields and their scan, the
dead account.SpendHint, account.GrantHints and the admin grant-hints
action; the in-game hint display now comes wholly from the payments hint
benefit. Banner eligibility and account merge no longer read the legacy
flags.

Tests: ads.test.ts (the client-mirrored gate), the codec ads round-trip,
the gateway ads transcode test, and a profile ads-config integration test
(cooldowns + suppressed under no-ads / no_banner). Docs: PAYMENTS §10 (+ru)
interstitial, the decision amends, backend README, the plan.

PLAN.md

@@ -35,7 +35,7 @@ status — without re-deriving decisions.
 | E3 | Wallet UI | 1 | DONE |
 | E4 | Durability (PITR) | 2 | DONE |
 | E5 | Payment intake | 2 | DONE |
-| E6 | Ads | 2 | WIP |
+| E6 | Ads | 2 | DONE |
 | E7 | Admin & reports | 2 | TODO |
 | E8 | Guest limits | — | TODO |
 | E9 | Tournament fee | future | TODO |
@@ -618,7 +618,7 @@ force-recreate when the Caddyfile changes.
 
 ## E6 — Ads
 
-**Status:** WIP · **Release 2** · depends on: E2 (chips), E5 (rewarded credits via intake) ·
+**Status:** DONE · **Release 2** · depends on: E2 (chips), E5 (rewarded credits via intake) ·
 mechanics: PAYMENTS §10.
 
 **Delivery & baked decisions.** Shipped as a linear PR stack (owner's choice): **rewarded first**,
@@ -640,8 +640,19 @@ VK returns **only `{result:true}`** (no token/signature) — client-attested is
 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.
+`CreateOrder`, not `spendableSources`, so VK-wallet chips spend on VK-iOS). Delivered on
+`feature/ads-interstitial` (the **interstitial + D31** slice): the post-move fullscreen interstitial
+as a **client-mirrored** gate — the backend `adsFor` puts the config cooldowns + a `suppressed` flag
+(the no-ads / `no_banner` gate, same as the banner) on the profile (`Profile.ads`), and
+`ui/src/lib/ads.ts` `maybeShowInterstitial` self-gates on the last-shown time per kind in
+`localStorage`, showing a VK interstitial (`vkShowInterstitial`) after a **confirmed play or a hint
+only** (never a pass / exchange / resign), VK-only, offline banner-only, with the same `VITE_ADS_STUB`
+toast on the contour. The slice also lands **D31 step 1 (contract-code)**: the domain no longer reads
+or writes the deprecated `accounts.hint_balance` / `paid_account` columns — the `Account` fields, the
+dead `account.SpendHint`, `account.GrantHints` and the admin **grant-hints** action are removed, and
+the in-game hint display now comes wholly from the payments benefit (`HintsAvailable`). The **columns
+stay** (no migration → image rollback is DB-safe); a later contract-PR does the `DROP` once E6 is
+stable on prod.
 
 **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
@@ -657,8 +668,9 @@ per-origin.
 - **Interstitial** (post-move fullscreen), configurable server values (from `payments`
   config): global per-user cooldown across all games (default 5 min); `vs_ai` 30 min; a hint
   application triggers a post-move interstitial independently with its own 1-min cooldown;
-  offline banner-only; respect VK's own frequency caps. Cooldown state tracked server-side
-  (per user) or client-mirrored from a server value — pick and document at implementation.
+  offline banner-only; respect VK's own frequency caps. Cooldown state is **client-mirrored**
+  (the chosen option): the server sends the cooldowns + `suppressed` on the profile and the
+  client self-gates on a per-kind last-shown time in `localStorage` — no per-move round-trip.
 - **Banner suppression:** extend `ads.Eligible` (`backend/internal/ads/ads.go` :107) to gate
   on the **origin benefit applicable in the current context** (E2 interface) instead of the
   single legacy flag. No-ads suppresses banner + interstitial; rewarded never suppressed.

backend/README.md

@@ -135,21 +135,23 @@ so `/internal/push-target` returns the recipient's `preferred_language` as the r
 language for out-of-app push; no per-bot routing remains. The console also manages the **advertising banner** (`/_gm/banners` +
 `/_gm/banner-settings`, `internal/ads`): operator campaigns with a percent weight, an optional
 window and bilingual messages, plus the global display timings. `GET /api/v1/user/profile` attaches
-the resolved, weighted campaign feed for an **eligible** viewer (`!paid_account && hint_balance == 0
-&& !no_banner` role, the message language picked by `preferred_language`); changing those inputs
-publishes a `notify` `banner` re-poll signal so the client shows/hides it in place. The shared wire
+the resolved, weighted campaign feed for an **eligible** viewer (no active **no-ads** benefit
+applicable in the current context and no **`no_banner`** role; the message language picked by
+`preferred_language`); changing those inputs
+publishes a `notify` `banner` re-poll signal so the client shows/hides it in place.
+The same gate drives the post-move interstitial config (`Profile.ads`, `adsFor`). The shared wire
 contracts live in the sibling [`../pkg`](../pkg) module.
 
 **Account linking & merge** (`/api/v1/user/link/*`). `internal/link`
 orchestrates it: an email confirm-code or a gateway-validated Telegram identity is
 attached to the current account, and when the identity already has its own account
-the two are merged in one transaction (`internal/accountmerge`) — stats and the hint
-wallet summed, `paid_account` ORed, identities/games/chat/complaints transferred,
+the two are merged in one transaction (`internal/accountmerge`) — stats summed,
+identities/games/chat/complaints transferred,
 friends/blocks de-duplicated, the secondary kept as a `merged_into` tombstone (so a
 shared finished game's foreign keys hold); a shared **active** game blocks the merge.
 The current account is primary, except a guest initiator whose linked identity has a
 durable owner — then the durable account wins and a fresh session is minted for it.
-The `accounts.paid_account`/`merged_into`/`merged_at` columns back this. This supersedes the
+The `accounts.merged_into`/`merged_at` columns back this. This supersedes the
 former `email.bind.*` edge surface (the `RequestCode`/`ConfirmCode` primitives stay).
 
 Rate-limit observability: the gateway posts its periodic rejection

backend/internal/account/account.go

@@ -43,9 +43,7 @@ var ErrNotFound = errors.New("account: not found")
 // local-time window (in TimeZone) during which the player is asleep, so the
 // turn-timeout sweeper does not auto-resign them inside it. (The robot opponent's
 // own sleep is anchored to its human opponent's timezone with a per-game drift,
-// computed in internal/robot, not from a robot account's away window.) HintBalance
-// is the player's wallet of purchasable hints, spent after a game's per-seat
-// allowance.
+// computed in internal/robot, not from a robot account's away window.)
 type Account struct {
 	ID                  uuid.UUID
 	DisplayName         string
@@ -53,7 +51,6 @@ type Account struct {
 	TimeZone            string
 	AwayStart           time.Time
 	AwayEnd             time.Time
-	HintBalance         int
 	BlockChat           bool
 	BlockFriendRequests bool
 	// VariantPreferences is the set of game variants (engine.Variant stable labels:
@@ -69,10 +66,6 @@ type Account struct {
 	// true (the default): the platform side-service skips out-of-app push for the
 	// account.
 	NotificationsInAppOnly bool
-	// PaidAccount marks a lifetime one-time-payment account. It is a service field
-	// (no purchase flow yet); an account linking & merge ORs it so a paid status is
-	// never lost when accounts are consolidated.
-	PaidAccount bool
 	// MergedInto is the primary account a retired (merged) secondary points at, or
 	// uuid.Nil for a live account. A tombstone keeps the row so the no-cascade
 	// foreign keys of a shared finished game stay valid.
@@ -563,52 +556,6 @@ func (s *Store) ProvisionGuest(ctx context.Context, browserTZ string) (Account,
 	return modelToAccount(row), nil
 }
 
-// SpendHint atomically decrements the account's hint wallet by one, returning
-// true when a hint was spent and false when the balance was already empty. The
-// guarded UPDATE keeps it safe under concurrent spends across the player's games.
-func (s *Store) SpendHint(ctx context.Context, id uuid.UUID) (bool, error) {
-	stmt := table.Accounts.
-		UPDATE(table.Accounts.HintBalance, table.Accounts.UpdatedAt).
-		SET(table.Accounts.HintBalance.SUB(postgres.Int(1)), postgres.TimestampzT(time.Now().UTC())).
-		WHERE(
-			table.Accounts.AccountID.EQ(postgres.UUID(id)).
-				AND(table.Accounts.HintBalance.GT(postgres.Int(0))),
-		)
-	res, err := stmt.ExecContext(ctx, s.db)
-	if err != nil {
-		return false, fmt.Errorf("account: spend hint %s: %w", id, err)
-	}
-	n, err := res.RowsAffected()
-	if err != nil {
-		return false, fmt.Errorf("account: spend hint rows %s: %w", id, err)
-	}
-	return n > 0, nil
-}
-
-// GrantHints adds n hints to the account's wallet and returns the new balance. n must be
-// positive: the additive update can only raise the balance, never lower it, so it enforces the
-// admin console's raise-only rule by construction and stays correct under a concurrent SpendHint.
-// It returns ErrNotFound when no account matches.
-func (s *Store) GrantHints(ctx context.Context, id uuid.UUID, n int) (int, error) {
-	if n <= 0 {
-		return 0, fmt.Errorf("account: grant hints %s: n must be positive, got %d", id, n)
-	}
-	stmt := table.Accounts.
-		UPDATE(table.Accounts.HintBalance, table.Accounts.UpdatedAt).
-		SET(table.Accounts.HintBalance.ADD(postgres.Int(int64(n))), postgres.TimestampzT(time.Now().UTC())).
-		WHERE(table.Accounts.AccountID.EQ(postgres.UUID(id))).
-		RETURNING(table.Accounts.HintBalance)
-
-	var row model.Accounts
-	if err := stmt.QueryContext(ctx, s.db, &row); err != nil {
-		if errors.Is(err, qrm.ErrNoRows) {
-			return 0, ErrNotFound
-		}
-		return 0, fmt.Errorf("account: grant hints %s: %w", id, err)
-	}
-	return int(row.HintBalance), nil
-}
-
 // FlagHighRate stamps the soft "suspected high-rate" marker with at, only when
 // the account is not already flagged — the first sustained episode wins, and a
 // re-flag after an operator clear starts a fresh timestamp. An infra marker, not
@@ -664,12 +611,10 @@ func modelToAccount(row model.Accounts) Account {
 		TimeZone:               row.TimeZone,
 		AwayStart:              row.AwayStart,
 		AwayEnd:                row.AwayEnd,
-		HintBalance:            int(row.HintBalance),
 		BlockChat:              row.BlockChat,
 		BlockFriendRequests:    row.BlockFriendRequests,
 		IsGuest:                row.IsGuest,
 		NotificationsInAppOnly: row.NotificationsInAppOnly,
-		PaidAccount:            row.PaidAccount,
 		MergedInto:             mergedInto,
 		FlaggedHighRateAt:      flaggedHighRateAt,
 		CreatedAt:              row.CreatedAt,

backend/internal/adminconsole/templates/pages/user_detail.gohtml

@@ -10,8 +10,6 @@
 <li><b>Timezone</b> {{.TimeZone}}</li>
 <li><b>Guest</b> {{if .Guest}}yes{{else}}no{{end}}</li>
 <li><b>Push</b> {{if .NotificationsInAppOnly}}in-app only{{else}}out-of-app{{end}}</li>
-<li><b>Paid</b> {{if .PaidAccount}}yes{{else}}no{{end}}</li>
-<li><b>Hint wallet</b> {{.HintBalance}}</li>
 {{if .MergedInto}}<li><b>Merged into</b> {{.MergedInto}}</li>{{end}}
 {{if .FlaggedHighRateAt}}<li><b>High-rate flag</b> <span class="warn">{{.FlaggedHighRateAt}}</span></li>{{end}}
 <li><b>Created</b> {{.CreatedAt}}</li>
@@ -21,10 +19,6 @@
 <button type="submit">Clear high-rate flag</button>
 </form>
 {{end}}
-<form class="form" method="post" action="/_gm/users/{{.ID}}/grant-hints">
-<label>Add hints <input type="number" name="amount" min="1" max="{{.HintGrantMax}}" value="1"></label>
-<button type="submit">Grant</button>
-</form>
 </section>
 <section class="panel"><h2>Statistics</h2>
 {{if .HasStats}}

backend/internal/adminconsole/views.go

@@ -149,7 +149,6 @@ type UserDetailView struct {
 	TimeZone               string
 	Guest                  bool
 	NotificationsInAppOnly bool
-	PaidAccount            bool
 	// MergedInto is the primary account id when this account has been retired by a
 	// merge, or empty for a live account.
 	MergedInto string
@@ -165,14 +164,10 @@ type UserDetailView struct {
 	// FlaggedHighRateAt is the pre-formatted soft high-rate marker timestamp,
 	// empty for an unflagged account; the card shows it with the Clear action.
 	FlaggedHighRateAt string
-	HintBalance       int
-	// HintGrantMax is the per-grant cap the operator's "add hints" form enforces (it mirrors the
-	// server's maxHintGrant), passed through so the policy value lives in one place.
-	HintGrantMax int
-	CreatedAt    string
-	HasStats     bool
-	Stats        StatsRow
-	Identities   []IdentityRow
+	CreatedAt         string
+	HasStats          bool
+	Stats             StatsRow
+	Identities        []IdentityRow
 	// HasEmail gates the "Erase email" action; set when the account carries an email identity.
 	HasEmail bool
 	Games    []GameRow

backend/internal/game/service.go

@@ -1272,10 +1272,6 @@ func (svc *Service) GameState(ctx context.Context, gameID, accountID uuid.UUID)
 	if !ok {
 		return StateView{}, ErrNotAPlayer
 	}
-	acc, err := svc.accounts.GetByID(ctx, accountID)
-	if err != nil {
-		return StateView{}, err
-	}
 
 	unlock := svc.locks.lock(gameID)
 	defer unlock()
@@ -1290,12 +1286,15 @@ func (svc *Service) GameState(ctx context.Context, gameID, accountID uuid.UUID)
 		}
 	}
 	return StateView{
-		Game:           pre,
-		Seat:           seat,
-		Rack:           g.Hand(seat),
-		BagLen:         g.BagLen(),
-		HintsRemaining: hintsRemaining(pre.HintsPerPlayer, pre.Seats[seat].HintsUsed, acc.HintBalance),
-		WalletBalance:  acc.HintBalance,
+		Game:   pre,
+		Seat:   seat,
+		Rack:   g.Hand(seat),
+		BagLen: g.BagLen(),
+		// The hint wallet moved to payments (svc.hintWallet); the deprecated accounts.hint_balance
+		// is no longer read, so the wire wallet is 0 and HintsRemaining is the per-seat allowance.
+		// The client adds the profile's payments hint balance on top (lib/hints.hintsLeft).
+		HintsRemaining: hintsRemaining(pre.HintsPerPlayer, pre.Seats[seat].HintsUsed, 0),
+		WalletBalance:  0,
 		// vs_ai idle-hint gate (seconds left; 0 for a human game / first move / not your turn).
 		HintUnlockLeftSeconds: hintUnlockLeftSeconds(pre, seat, svc.clock()),
 	}, nil

backend/internal/inttest/admin_test.go

@@ -4,7 +4,6 @@ package inttest
 
 import (
 	"context"
-	"errors"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -280,76 +279,6 @@ func TestConsoleThrottledViewAndFlagClear(t *testing.T) {
 	}
 }
 
-// TestConsoleGrantHints drives the admin hint-wallet grant end to end: the card shows the form,
-// the action is CSRF-guarded, a same-origin grant adds to the wallet, a second grant adds again
-// (rather than replacing), the inclusive per-grant cap is accepted, and an out-of-range or
-// non-numeric amount is refused without changing the balance.
-func TestConsoleGrantHints(t *testing.T) {
-	ctx := context.Background()
-	accounts := account.NewStore(testDB)
-	id := provisionAccount(t)
-	srv := server.New(":0", server.Deps{
-		Logger: zap.NewNop(), Accounts: accounts, Games: newGameService(), Registry: testRegistry, DictDir: dictDir(),
-	})
-	h := srv.Handler()
-	base := "http://admin.test/_gm/users/" + id.String()
-
-	if code, body := consoleDo(h, http.MethodGet, base, "", ""); code != http.StatusOK || !strings.Contains(body, "Add hints") {
-		t.Fatalf("user card = %d, has grant form = %v", code, strings.Contains(body, "Add hints"))
-	}
-	// The grant POST is CSRF-guarded like every console action.
-	if code, _ := consoleDo(h, http.MethodPost, base+"/grant-hints", "amount=5", ""); code != http.StatusForbidden {
-		t.Fatalf("grant without origin = %d, want 403", code)
-	}
-	// A same-origin grant adds to the wallet.
-	if code, body := consoleDo(h, http.MethodPost, base+"/grant-hints", "amount=5", "http://admin.test"); code != http.StatusOK || !strings.Contains(body, "now 5") {
-		t.Fatalf("grant 5 = %d, body has 'now 5' = %v", code, strings.Contains(body, "now 5"))
-	}
-	if acc, err := accounts.GetByID(ctx, id); err != nil || acc.HintBalance != 5 {
-		t.Fatalf("after grant 5: balance=%d err=%v, want 5", acc.HintBalance, err)
-	}
-	// A second grant adds again rather than replacing.
-	if code, body := consoleDo(h, http.MethodPost, base+"/grant-hints", "amount=3", "http://admin.test"); code != http.StatusOK || !strings.Contains(body, "now 8") {
-		t.Fatalf("grant 3 = %d, body has 'now 8' = %v", code, strings.Contains(body, "now 8"))
-	}
-	// An out-of-range or non-numeric amount is refused; the balance is left untouched.
-	for _, bad := range []string{"0", "-1", "101", "x", ""} {
-		if code, body := consoleDo(h, http.MethodPost, base+"/grant-hints", "amount="+bad, "http://admin.test"); code != http.StatusOK || !strings.Contains(body, "Invalid amount") {
-			t.Fatalf("grant %q = %d, has 'Invalid amount' = %v", bad, code, strings.Contains(body, "Invalid amount"))
-		}
-	}
-	if acc, err := accounts.GetByID(ctx, id); err != nil || acc.HintBalance != 8 {
-		t.Fatalf("after invalid grants: balance=%d err=%v, want 8", acc.HintBalance, err)
-	}
-	// The inclusive per-grant cap (100) is accepted.
-	if code, _ := consoleDo(h, http.MethodPost, base+"/grant-hints", "amount=100", "http://admin.test"); code != http.StatusOK {
-		t.Fatalf("grant 100 = %d, want 200", code)
-	}
-	if acc, err := accounts.GetByID(ctx, id); err != nil || acc.HintBalance != 108 {
-		t.Fatalf("after grant 100: balance=%d err=%v, want 108", acc.HintBalance, err)
-	}
-}
-
-// TestGrantHintsStore covers the wallet store method directly: an additive grant raises the
-// balance, a non-positive grant is rejected, and an unknown account yields ErrNotFound.
-func TestGrantHintsStore(t *testing.T) {
-	ctx := context.Background()
-	accounts := account.NewStore(testDB)
-	id := provisionAccount(t)
-	if bal, err := accounts.GrantHints(ctx, id, 4); err != nil || bal != 4 {
-		t.Fatalf("grant 4 = (%d, %v), want (4, nil)", bal, err)
-	}
-	if bal, err := accounts.GrantHints(ctx, id, 6); err != nil || bal != 10 {
-		t.Fatalf("grant 6 = (%d, %v), want (10, nil)", bal, err)
-	}
-	if _, err := accounts.GrantHints(ctx, id, 0); err == nil {
-		t.Error("grant 0 should be rejected (non-positive)")
-	}
-	if _, err := accounts.GrantHints(ctx, uuid.New(), 1); !errors.Is(err, account.ErrNotFound) {
-		t.Errorf("grant unknown account = %v, want ErrNotFound", err)
-	}
-}
-
 // consoleDo issues a request to h, optionally with an Origin header, and returns
 // the status and body. Form bodies are sent as application/x-www-form-urlencoded.
 func consoleDo(h http.Handler, method, target, body, origin string) (int, string) {

backend/internal/inttest/banner_console_test.go

@@ -191,7 +191,7 @@ func TestBannerMessageOwnership(t *testing.T) {
 	}
 }
 
-// profileBanner is the banner block of the profile.get JSON response.
+// profileBanner is the banner (and interstitial-ad) block of the profile.get JSON response.
 type profileBanner struct {
 	Banner *struct {
 		Campaigns []struct {
@@ -203,6 +203,12 @@ type profileBanner struct {
 			HoldMs int `json:"hold_ms"`
 		} `json:"timings"`
 	} `json:"banner"`
+	Ads *struct {
+		CooldownGlobalS int  `json:"cooldown_global_s"`
+		CooldownVsAiS   int  `json:"cooldown_vs_ai_s"`
+		CooldownHintS   int  `json:"cooldown_hint_s"`
+		Suppressed      bool `json:"suppressed"`
+	} `json:"ads"`
 }
 
 // TestBannerProfileEligibility checks the profile.get banner block follows
@@ -283,6 +289,81 @@ func TestBannerProfileEligibility(t *testing.T) {
 	}
 }
 
+// TestProfileAdsConfig checks the profile.get interstitial-ad block: the seeded config cooldowns are
+// carried through, and Suppressed follows the same no-ads / no_banner gate as the banner (the client
+// self-gates VK-only + online on top). The no_banner role is context-independent; the no-ads benefit
+// applies only in a trusted context where its segment is present.
+func TestProfileAdsConfig(t *testing.T) {
+	ctx := context.Background()
+	srv, _, pay := bannerServer(t)
+	accounts := account.NewStore(testDB)
+	id := provisionAccount(t)
+
+	get := func() profileBanner {
+		t.Helper()
+		rec := userGet(t, srv, "/api/v1/user/profile", id)
+		if rec.Code != http.StatusOK {
+			t.Fatalf("profile = %d, want 200", rec.Code)
+		}
+		var p profileBanner
+		if err := json.Unmarshal(rec.Body.Bytes(), &p); err != nil {
+			t.Fatalf("decode profile: %v", err)
+		}
+		return p
+	}
+	getTG := func() profileBanner {
+		t.Helper()
+		rec := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodGet, "/api/v1/user/profile", nil)
+		req.Header.Set("X-User-ID", id.String())
+		req.Header.Set("X-Platform", "telegram/android")
+		srv.Handler().ServeHTTP(rec, req)
+		if rec.Code != http.StatusOK {
+			t.Fatalf("profile = %d, want 200", rec.Code)
+		}
+		var p profileBanner
+		if err := json.Unmarshal(rec.Body.Bytes(), &p); err != nil {
+			t.Fatalf("decode profile: %v", err)
+		}
+		return p
+	}
+
+	// A free account: the ads block carries the seeded config cooldowns and is not suppressed.
+	p := get()
+	if p.Ads == nil {
+		t.Fatal("free account: no ads block")
+	}
+	if p.Ads.CooldownGlobalS != 300 || p.Ads.CooldownVsAiS != 1800 || p.Ads.CooldownHintS != 60 {
+		t.Fatalf("cooldowns = %d/%d/%d, want 300/1800/60", p.Ads.CooldownGlobalS, p.Ads.CooldownVsAiS, p.Ads.CooldownHintS)
+	}
+	if p.Ads.Suppressed {
+		t.Fatal("free account: interstitials must not be suppressed")
+	}
+
+	// The no_banner role suppresses interstitials too (context-independent).
+	if err := accounts.GrantRole(ctx, id, account.RoleNoBanner); err != nil {
+		t.Fatalf("grant role: %v", err)
+	}
+	if p := get(); p.Ads == nil || !p.Ads.Suppressed {
+		t.Fatalf("no_banner role: ads=%v, want suppressed", p.Ads)
+	}
+	if err := accounts.RevokeRole(ctx, id, account.RoleNoBanner); err != nil {
+		t.Fatalf("revoke role: %v", err)
+	}
+
+	// An active no-ads benefit suppresses interstitials in a trusted context; an untrusted context
+	// does not apply it (fail-closed to eligible, as for the banner).
+	if err := pay.Grant(ctx, id, payments.SourceTelegram, 0, 30, false); err != nil {
+		t.Fatalf("grant no-ads: %v", err)
+	}
+	if p := getTG(); p.Ads == nil || !p.Ads.Suppressed {
+		t.Fatalf("no-ads benefit (trusted): ads=%v, want suppressed", p.Ads)
+	}
+	if p := get(); p.Ads == nil || p.Ads.Suppressed {
+		t.Fatalf("no-ads benefit (untrusted): ads=%v, want NOT suppressed", p.Ads)
+	}
+}
+
 // TestBannerSurvivesProfileUpdate guards that a profile update (e.g. a language switch) returns the
 // banner block too, so the client's profile keeps the banner instead of losing it until reload.
 func TestBannerSurvivesProfileUpdate(t *testing.T) {
@@ -440,10 +521,4 @@ func TestBannerUrgentBypassesEligibility(t *testing.T) {
 	if err := accounts.RevokeRole(ctx, id, account.RoleNoBanner); err != nil {
 		t.Fatalf("revoke role: %v", err)
 	}
-
-	// A non-empty hint wallet no longer suppresses it either.
-	if _, err := accounts.GrantHints(ctx, id, 5); err != nil {
-		t.Fatalf("grant hints: %v", err)
-	}
-	assertUrgentOnly("hints", get())
 }

backend/internal/payments/service_intake.go

@@ -140,6 +140,12 @@ func (s *Service) ValidatePreCheckout(ctx context.Context, orderID uuid.UUID, am
 // them.
 const providerVKAds = "vk_ads"
 
+// InterstitialCooldowns reports the post-move interstitial-ad cooldowns (seconds): global, vs_ai and
+// the independent hint-triggered one. The client mirrors them and self-gates (client-mirrored, D30).
+func (s *Service) InterstitialCooldowns(ctx context.Context) (global, vsAi, hint int, err error) {
+	return s.store.interstitialCooldowns(ctx)
+}
+
 // RewardPayout reports the chips a rewarded-video view earns in the caller's context — the config
 // payout in a trusted VK context with the VK segment attached, and 0 everywhere else (rewarded is
 // VK-only, D28). The client uses it to gate the "watch for chips" button.

backend/internal/payments/store_intake.go

@@ -385,6 +385,20 @@ type RewardOutcome struct {
 	AlreadyCredited bool
 }
 
+// interstitialCooldowns reads the post-move interstitial-ad cooldowns (seconds): the global
+// per-user cooldown, the longer vs_ai one, and the independent hint-triggered one. The client mirrors
+// them and self-gates (E6/D30).
+func (s *Store) interstitialCooldowns(ctx context.Context) (global, vsAi, hint int, err error) {
+	var cfg model.Config
+	if e := postgres.SELECT(table.Config.CooldownGlobalSeconds, table.Config.CooldownVsAiSeconds, table.Config.CooldownHintSeconds).
+		FROM(table.Config).
+		LIMIT(1).
+		QueryContext(ctx, s.db, &cfg); e != nil {
+		return 0, 0, 0, fmt.Errorf("payments: read interstitial cooldowns: %w", e)
+	}
+	return int(cfg.CooldownGlobalSeconds), int(cfg.CooldownVsAiSeconds), int(cfg.CooldownHintSeconds), nil
+}
+
 // rewardConfig reads the rewarded payout (chips per view) and the per-day and per-hour caps. The
 // caps are both anti-abuse (bounding a forger's free chips) and an economic conversion lever (free
 // rewarded chips are limited so a player who wants more buys) — tuned in the admin.

backend/internal/server/banner.go

@@ -57,9 +57,9 @@ type bannerTimingsDTO struct {
 func (s *Server) profileResponse(ctx context.Context, acc account.Account) profileResponse {
 	r := profileResponseFor(acc)
 	// Resolve the payments gate once (execution context + present sources) and feed it to both
-	// the hint count and the banner. The profile hint balance now comes from the payments benefit
-	// (context-aware), not the deprecated accounts.hint_balance column; on any failure the legacy
-	// value from profileResponseFor (zeroed in production) stands.
+	// the hint count and the banner. The profile hint balance comes from the payments benefit
+	// (context-aware); the deprecated accounts.hint_balance column is no longer read, so on any
+	// failure the fallback from profileResponseFor is a plain 0.
 	cxt, present, err := s.walletGate(ctx, acc.ID)
 	if err != nil {
 		s.log.Warn("profile: wallet gate failed", zap.String("account", acc.ID.String()), zap.Error(err))
@@ -71,6 +71,7 @@ func (s *Server) profileResponse(ctx context.Context, acc account.Account) profi
 		}
 	}
 	r.Banner = s.bannerFor(ctx, acc, cxt, present)
+	r.Ads = s.adsFor(ctx, acc, cxt, present)
 	s.fillLinkedIdentities(ctx, &r, acc.ID)
 	r.DictVersions = s.currentDictVersions()
 	return r
@@ -177,6 +178,44 @@ func (s *Server) bannerFor(ctx context.Context, acc account.Account, cxt payment
 	}
 }
 
+// adsDTO is the post-move interstitial config in the profile: the client-mirrored cooldowns
+// (seconds) and whether ads are suppressed in the context (a no-ads benefit applicable here, or the
+// no_banner role). The client shows a VK interstitial after a confirmed move / hint only when not
+// suppressed and the mirrored cooldown has elapsed.
+type adsDTO struct {
+	CooldownGlobalS int  `json:"cooldown_global_s"`
+	CooldownVsAiS   int  `json:"cooldown_vs_ai_s"`
+	CooldownHintS   int  `json:"cooldown_hint_s"`
+	Suppressed      bool `json:"suppressed"`
+}
+
+// adsFor builds the profile interstitial-ad config: the cooldowns and whether ads are suppressed
+// here (the same no-ads / no_banner gate as the banner). A read failure logs and yields a suppressed
+// block (fail-safe: no interstitial), so the profile still succeeds.
+func (s *Server) adsFor(ctx context.Context, acc account.Account, cxt payments.Context, present []payments.Source) *adsDTO {
+	if s.payments == nil {
+		return nil
+	}
+	global, vsAi, hint, err := s.payments.InterstitialCooldowns(ctx)
+	if err != nil {
+		s.log.Warn("profile: ad cooldowns read failed", zap.String("account", acc.ID.String()), zap.Error(err))
+		return &adsDTO{Suppressed: true}
+	}
+	suppressed := false
+	if adFree, aerr := s.payments.AdFree(ctx, acc.ID, cxt, present); aerr != nil {
+		s.log.Warn("profile: ad-free read failed", zap.String("account", acc.ID.String()), zap.Error(aerr))
+		suppressed = true // fail-safe: suppress the interstitial when eligibility is unknown
+	} else {
+		suppressed = adFree
+	}
+	if !suppressed {
+		if noBanner, berr := s.accounts.HasRole(ctx, acc.ID, account.RoleNoBanner); berr == nil {
+			suppressed = noBanner
+		}
+	}
+	return &adsDTO{CooldownGlobalS: global, CooldownVsAiS: vsAi, CooldownHintS: hint, Suppressed: suppressed}
+}
+
 // bannerCampaignFromActive flattens a resolved campaign into its wire DTO,
 // projecting each optional colour set into its three "#rrggbb" fields (empty when
 // the set is absent, so JSON omitempty drops them).

backend/internal/server/dto.go

@@ -60,6 +60,11 @@ type profileResponse struct {
 	// see the banner (a free account with an empty hint wallet and without the
 	// no_banner role), absent otherwise. See banner.go.
 	Banner *bannerDTO `json:"banner,omitempty"`
+	// Ads carries the post-move interstitial config for the client's client-mirrored gate: the
+	// cooldowns (seconds) and whether ads are suppressed in this context (no-ads / no_banner role).
+	// The client shows a VK interstitial after a confirmed move / hint when not suppressed and the
+	// cooldown has elapsed. Always present (the client also gates VK-only + online itself).
+	Ads *adsDTO `json:"ads,omitempty"`
 	// Email is the account's confirmed email address ("" when none); TelegramLinked and
 	// VkLinked report whether a platform identity is attached. They drive the profile's
 	// link / unlink / change-email controls, and are filled outside the pure projection
@@ -218,13 +223,15 @@ func sessionResponseFor(token string, acc account.Account) sessionResponse {
 // profileResponseFor projects an account into its profile DTO.
 func profileResponseFor(acc account.Account) profileResponse {
 	return profileResponse{
-		UserID:                 acc.ID.String(),
-		DisplayName:            acc.DisplayName,
-		PreferredLanguage:      acc.PreferredLanguage,
-		TimeZone:               acc.TimeZone,
-		AwayStart:              acc.AwayStart.Format(awayTimeLayout),
-		AwayEnd:                acc.AwayEnd.Format(awayTimeLayout),
-		HintBalance:            acc.HintBalance,
+		UserID:            acc.ID.String(),
+		DisplayName:       acc.DisplayName,
+		PreferredLanguage: acc.PreferredLanguage,
+		TimeZone:          acc.TimeZone,
+		AwayStart:         acc.AwayStart.Format(awayTimeLayout),
+		AwayEnd:           acc.AwayEnd.Format(awayTimeLayout),
+		// The hint balance comes from the payments benefit; profileResponse overrides this
+		// with the context-aware count. This zero is the fallback when that read fails.
+		HintBalance:            0,
 		BlockChat:              acc.BlockChat,
 		BlockFriendRequests:    acc.BlockFriendRequests,
 		IsGuest:                acc.IsGuest,

backend/internal/server/handlers_admin_console.go

@@ -29,10 +29,6 @@ import (
 // adminPageSize is the page size of the admin console's paginated lists.
 const adminPageSize = 50
 
-// maxHintGrant caps a single operator hint grant. Grants are additive and can never lower a
-// wallet, so a fat-fingered grant cannot be undone through this form; the cap bounds one mistake.
-const maxHintGrant = 100
-
 // registerConsole mounts the server-rendered admin console under /_gm. The gateway
 // puts HTTP Basic-Auth in front of /_gm and reverse-proxies it verbatim; the
 // backend trusts the gateway (as for all of /api) and adds only a same-origin guard
@@ -56,7 +52,6 @@ func (s *Server) registerConsole(router *gin.Engine) {
 	gm.GET("/users/:id", s.consoleUserDetail)
 	gm.POST("/users/:id/message", s.consoleUserMessage)
 	gm.POST("/users/:id/clear-high-rate-flag", s.consoleClearHighRateFlag)
-	gm.POST("/users/:id/grant-hints", s.consoleGrantHints)
 	gm.POST("/users/:id/block", s.consoleBlockUser)
 	gm.POST("/users/:id/unblock", s.consoleUnblockUser)
 	gm.POST("/users/:id/grant-role", s.consoleGrantRole)
@@ -354,7 +349,6 @@ func (s *Server) consoleUserDetail(c *gin.Context) {
 	view := adminconsole.UserDetailView{
 		ID: acc.ID.String(), DisplayName: acc.DisplayName, Language: acc.PreferredLanguage,
 		TimeZone: acc.TimeZone, Guest: acc.IsGuest, NotificationsInAppOnly: acc.NotificationsInAppOnly,
-		PaidAccount: acc.PaidAccount, HintBalance: acc.HintBalance, HintGrantMax: maxHintGrant,
 		CreatedAt: fmtTime(acc.CreatedAt), HasStats: !acc.IsGuest, ConnectorEnabled: s.connector != nil,
 	}
 	if acc.MergedInto != uuid.Nil {
@@ -963,30 +957,6 @@ func (s *Server) consoleClearHighRateFlag(c *gin.Context) {
 	s.renderConsoleMessage(c, "Cleared", "high-rate flag cleared", "/_gm/users/"+id.String())
 }
 
-// consoleGrantHints adds hints to a user's wallet. The grant is additive (raise-only): it tops a
-// player up and can never lower what they already hold, so blocking a reduction is inherent rather
-// than a separate guard. A single grant is bounded by maxHintGrant.
-func (s *Server) consoleGrantHints(c *gin.Context) {
-	id, ok := s.consoleUUID(c, "/_gm/users")
-	if !ok {
-		return
-	}
-	back := "/_gm/users/" + id.String()
-	n, err := strconv.Atoi(trimForm(c, "amount"))
-	if err != nil || n < 1 || n > maxHintGrant {
-		s.renderConsoleMessage(c, "Invalid amount", fmt.Sprintf("enter a whole number of hints to add, between 1 and %d", maxHintGrant), back)
-		return
-	}
-	balance, err := s.accounts.GrantHints(c.Request.Context(), id, n)
-	if err != nil {
-		s.consoleError(c, err)
-		return
-	}
-	// A non-empty hint wallet removes the banner: nudge an open client to re-check.
-	s.publishBannerChange(id)
-	s.renderConsoleMessage(c, "Granted", fmt.Sprintf("added %d hint(s); the wallet is now %d", n, balance), back)
-}
-
 // consoleRemoveEmail deletes the account's bound email identity (and any pending
 // confirmations), freeing the address. It refuses to remove the account's only
 // identity, which would leave it unreachable.

docs/PAYMENTS.md

@@ -280,12 +280,19 @@ not suppressed by no-ads (D9). A future network that offers a server verify slot
 abstraction. On the test contour a build flag (`VITE_ADS_STUB`) swaps a toast for the real ad; prod
 always shows real ads (a failed real ad must not credit).
 
-**Interstitial** (post-move fullscreen), configurable server-side values:
+**Interstitial** (fullscreen after a confirmed play), **VK-only**, configurable server-side
+values. The gate is **client-mirrored**: the profile carries the cooldowns and a `suppressed`
+flag (the same no-ads / `no_banner` gate as the banner, resolved server-side in `adsFor`), and
+the client self-gates on the last-shown time **per kind** in `localStorage` — no per-move
+server round-trip. The contour `VITE_ADS_STUB` swaps the same "ad fired" toast for the real ad.
+Values:
 
 - Global cooldown **per user, across all games**, default **5 min**.
 - **`vs_ai` — 30 min** (aligned with the hint cooldown, so it does not scare casual players).
-- Applying a **hint** triggers a post-move interstitial **independently** of the main
-  cooldown, with its own **1-min** cooldown.
+- Applying a **hint** triggers an interstitial **independently** of the main cooldown, with
+  its own **1-min** cooldown.
+- Fires **only after a confirmed play or a hint** — never after a pass, exchange or resign
+  (an ad for a non-scoring action would only annoy, so those are never "rewarded" with one).
 - Offline — banner only.
 - Respect VK's own frequency caps.
 

docs/PAYMENTS_DECISIONS_ru.md

@@ -175,12 +175,24 @@ web+PWA / native Android+iOS через Capacitor). Владелец (самоз
   (соосно кулдауну подсказок). Применение **подсказки** триггерит ролик после хода
   **независимо** от основного кулдауна, со своим кулдауном **1 мин**. Оффлайн — только
   баннер. Уважать собственные лимиты частоты VK.
+  **АМЕНД (E6, по факту реализации):** гейт **зеркальный** — сервер отдаёт кулдауны и `suppressed`
+  в профиле (`adsFor`), клиент сам гейтит по времени последнего показа на каждый вид в `localStorage`
+  (без раунд-трипа на ход). Ролик показывается **только после подтверждённого хода или подсказки** —
+  **не** после пропуска, обмена или сдачи (за не-очковое действие рекламой не «награждаем»).
+  Interstitial — **только VK** (как и rewarded).
 - **D31. `paid_account` тоже deprecated** → удаление из схемы (как `hint_balance`), в
   пользу per-origin бенефитов «без рекламы». Существующий `ads.Eligible`
   (`backend/internal/ads/ads.go:107`) расширяется: баннер гасится по origin-бенефиту,
   **применимому в текущем контексте**, а не по одному глобальному флагу. Legacy
   `paid_account`/`hint_balance` в проде никем не выставлены (потока покупки не было) →
   обнуляем/игнорируем, после релиза платежей дропаем.
+  **АМЕНД (E6, по факту реализации — expand-contract, шаг 1 «contract-код»):** доменное
+  использование обеих колонок **убрано** — поля `Account.HintBalance` / `Account.PaidAccount`,
+  их скан, мёртвый `account.SpendHint`, `account.GrantHints` и админ-действие
+  «grant-hints» (роут `/_gm/users/:id/grant-hints`, форма, `UserDetailView.HintBalance`/
+  `PaidAccount`); отображение подсказок в игре теперь всегда из payments (`HintsAvailable`),
+  профильный баланс — из payments-бенефита. **Колонки БД пока оставлены** (без миграции —
+  откат образа DB-safe); их `DROP` — отдельным contract-PR, когда E6 стабилен на проде.
 - **D32. Каталог — конфигурируемый (БД + админка).** Базовые ценности (атомы
   начисления): Фишки, подсказки, дни-без-рекламы, участие-в-турнире. **Продукт = набор
   атомов + цена** (по одной ценности или комбо). «Пакет Фишек» — цена **per-метод**

docs/PAYMENTS_ru.md

@@ -279,12 +279,18 @@ App отдаёт только клиентский результат просм
 гасится «без рекламы» (D9). Сеть с серверным verify встроится за ads-абстракцией. На тест-контуре
 build-флаг (`VITE_ADS_STUB`) подменяет ролик тостом; прод всегда крутит настоящую рекламу.
 
-**Полноэкранный ролик** (после хода), конфигурируемые серверные значения:
+**Полноэкранный ролик** (после подтверждённого хода), **только VK**, конфигурируемые серверные
+значения. Гейт **зеркалится на клиенте**: профиль несёт кулдауны и флаг `suppressed` (тот же гейт
+«без рекламы» / `no_banner`, что и у баннера, считается на сервере в `adsFor`), а клиент сам
+гейтит по времени последнего показа **на каждый вид** в `localStorage` — без серверного раунд-трипа
+на каждый ход. Контурный `VITE_ADS_STUB` подменяет ролик тем же тостом «ad fired». Значения:
 
 - Глобальный кулдаун **на пользователя, сквозь все партии**, дефолт **5 мин**.
 - **`vs_ai` — 30 мин** (соосно кулдауну подсказок, чтобы не отпугивать казуалов).
-- Применение **подсказки** триггерит ролик после хода **независимо** от основного кулдауна,
-  со своим кулдауном **1 мин**.
+- Применение **подсказки** триггерит ролик **независимо** от основного кулдауна, со своим
+  кулдауном **1 мин**.
+- Показывается **только после подтверждённого хода или подсказки** — никогда после пропуска,
+  обмена или сдачи (ролик за не-очковое действие только раздражает, за них не «награждаем»).
 - Оффлайн — только баннер.
 - Уважать собственные лимиты частоты VK.
 

gateway/internal/backendclient/api.go

@@ -37,6 +37,8 @@ type ProfileResp struct {
 	// Banner is the advertising-banner block, present only for a viewer eligible to
 	// see the banner. The gateway forwards it verbatim into the Profile payload.
 	Banner *BannerResp `json:"banner,omitempty"`
+	// Ads is the post-move interstitial config (cooldowns + suppressed) for the client-mirrored gate.
+	Ads *AdsResp `json:"ads,omitempty"`
 	// Email is the confirmed email ("" when none); TelegramLinked/VkLinked report an
 	// attached platform identity — they drive the profile's link/unlink/change controls.
 	Email          string `json:"email"`
@@ -47,6 +49,15 @@ type ProfileResp struct {
 	DictVersions []DictVersion `json:"dict_versions,omitempty"`
 }
 
+// AdsResp is the post-move interstitial config in the profile: the client-mirrored cooldowns
+// (seconds) and whether ads are suppressed in the caller's context.
+type AdsResp struct {
+	CooldownGlobalS int  `json:"cooldown_global_s"`
+	CooldownVsAiS   int  `json:"cooldown_vs_ai_s"`
+	CooldownHintS   int  `json:"cooldown_hint_s"`
+	Suppressed      bool `json:"suppressed"`
+}
+
 // DictVersion pairs a game variant's stable label with its current dictionary version.
 type DictVersion struct {
 	Variant string `json:"variant"`

gateway/internal/transcode/encode.go

@@ -184,6 +184,16 @@ func encodeProfile(p backendclient.ProfileResp) []byte {
 	}
 	prefs := buildStringVector(b, p.VariantPreferences, fb.ProfileStartVariantPreferencesVector)
 	dictVersions := encodeDictVersions(b, p.DictVersions)
+	// The interstitial-ad config table (scalars only), built before Profile is opened.
+	var ads flatbuffers.UOffsetT
+	if p.Ads != nil {
+		fb.AdsInfoStart(b)
+		fb.AdsInfoAddCooldownGlobalS(b, int32(p.Ads.CooldownGlobalS))
+		fb.AdsInfoAddCooldownVsAiS(b, int32(p.Ads.CooldownVsAiS))
+		fb.AdsInfoAddCooldownHintS(b, int32(p.Ads.CooldownHintS))
+		fb.AdsInfoAddSuppressed(b, p.Ads.Suppressed)
+		ads = fb.AdsInfoEnd(b)
+	}
 	fb.ProfileStart(b)
 	fb.ProfileAddUserId(b, uid)
 	fb.ProfileAddDisplayName(b, name)
@@ -206,6 +216,9 @@ func encodeProfile(p backendclient.ProfileResp) []byte {
 	if p.Banner != nil {
 		fb.ProfileAddBanner(b, banner)
 	}
+	if p.Ads != nil {
+		fb.ProfileAddAds(b, ads)
+	}
 	b.Finish(fb.ProfileEnd(b))
 	return b.FinishedBytes()
 }

gateway/internal/transcode/transcode_ads_test.go

@@ -0,0 +1,65 @@
+package transcode_test
+
+import (
+	"context"
+	"net/http"
+	"testing"
+
+	"scrabble/gateway/internal/transcode"
+	fb "scrabble/pkg/fbs/scrabblefb"
+)
+
+// TestProfileGetEncodesAds verifies the gateway forwards the backend's interstitial-ad block
+// into the Profile payload: the three cooldowns and the suppressed flag the client-mirrored gate
+// reads. The encode is not exercised by the mock e2e (it bypasses the codec), so a dropped field
+// would only surface here.
+func TestProfileGetEncodesAds(t *testing.T) {
+	backend, cleanup := fakeBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet || r.URL.Path != "/api/v1/user/profile" {
+			t.Errorf("unexpected %s %q", r.Method, r.URL.Path)
+		}
+		_, _ = w.Write([]byte(`{"user_id":"u-1","display_name":"Kaya","preferred_language":"en",` +
+			`"ads":{"cooldown_global_s":300,"cooldown_vs_ai_s":1800,"cooldown_hint_s":60,"suppressed":true}}`))
+	})
+	defer cleanup()
+
+	reg := transcode.NewRegistry(backend, nil)
+	op, ok := reg.Lookup(transcode.MsgProfileGet)
+	if !ok {
+		t.Fatal("profile.get not registered")
+	}
+	payload, err := op.Handler(context.Background(), transcode.Request{UserID: "u-1"})
+	if err != nil {
+		t.Fatalf("handler: %v", err)
+	}
+
+	ads := fb.GetRootAsProfile(payload, 0).Ads(nil)
+	if ads == nil {
+		t.Fatal("profile carries no ads block")
+	}
+	if ads.CooldownGlobalS() != 300 || ads.CooldownVsAiS() != 1800 || ads.CooldownHintS() != 60 {
+		t.Errorf("cooldowns = %d/%d/%d, want 300/1800/60", ads.CooldownGlobalS(), ads.CooldownVsAiS(), ads.CooldownHintS())
+	}
+	if !ads.Suppressed() {
+		t.Error("suppressed = false, want true")
+	}
+}
+
+// TestProfileGetNoAds verifies a profile without an ads block encodes none (the backend omits it
+// only on an internal failure; normally the block is always present).
+func TestProfileGetNoAds(t *testing.T) {
+	backend, cleanup := fakeBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		_, _ = w.Write([]byte(`{"user_id":"u-1","display_name":"Kaya","preferred_language":"en"}`))
+	})
+	defer cleanup()
+
+	reg := transcode.NewRegistry(backend, nil)
+	op, _ := reg.Lookup(transcode.MsgProfileGet)
+	payload, err := op.Handler(context.Background(), transcode.Request{UserID: "u-1"})
+	if err != nil {
+		t.Fatalf("handler: %v", err)
+	}
+	if p := fb.GetRootAsProfile(payload, 0); p.Ads(nil) != nil {
+		t.Error("profile without an ads block unexpectedly carries one")
+	}
+}

pkg/fbs/scrabble.fbs

@@ -264,6 +264,18 @@ table Profile {
   // preload the right dictionary and pin a new local game without a separate request (added
   // trailing — backward-compatible).
   dict_versions:[DictVersion];
+  // ads carries the post-move interstitial config (cooldowns + suppressed) for the client-mirrored
+  // gate (added trailing — backward-compatible).
+  ads:AdsInfo;
+}
+
+// AdsInfo is the post-move interstitial config: the client-mirrored cooldowns (seconds) and whether
+// ads are suppressed in the caller's context (a no-ads benefit here, or the no_banner role).
+table AdsInfo {
+  cooldown_global_s:int;
+  cooldown_vs_ai_s:int;
+  cooldown_hint_s:int;
+  suppressed:bool;
 }
 
 // BlockStatus reports the caller's current manual block. The UI fetches it after any operation

pkg/fbs/scrabblefb/AdsInfo.go

@@ -0,0 +1,109 @@
+// Code generated by the FlatBuffers compiler. DO NOT EDIT.
+
+package scrabblefb
+
+import (
+	flatbuffers "github.com/google/flatbuffers/go"
+)
+
+type AdsInfo struct {
+	_tab flatbuffers.Table
+}
+
+func GetRootAsAdsInfo(buf []byte, offset flatbuffers.UOffsetT) *AdsInfo {
+	n := flatbuffers.GetUOffsetT(buf[offset:])
+	x := &AdsInfo{}
+	x.Init(buf, n+offset)
+	return x
+}
+
+func FinishAdsInfoBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.Finish(offset)
+}
+
+func GetSizePrefixedRootAsAdsInfo(buf []byte, offset flatbuffers.UOffsetT) *AdsInfo {
+	n := flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])
+	x := &AdsInfo{}
+	x.Init(buf, n+offset+flatbuffers.SizeUint32)
+	return x
+}
+
+func FinishSizePrefixedAdsInfoBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.FinishSizePrefixed(offset)
+}
+
+func (rcv *AdsInfo) Init(buf []byte, i flatbuffers.UOffsetT) {
+	rcv._tab.Bytes = buf
+	rcv._tab.Pos = i
+}
+
+func (rcv *AdsInfo) Table() flatbuffers.Table {
+	return rcv._tab
+}
+
+func (rcv *AdsInfo) CooldownGlobalS() int32 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(4))
+	if o != 0 {
+		return rcv._tab.GetInt32(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *AdsInfo) MutateCooldownGlobalS(n int32) bool {
+	return rcv._tab.MutateInt32Slot(4, n)
+}
+
+func (rcv *AdsInfo) CooldownVsAiS() int32 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		return rcv._tab.GetInt32(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *AdsInfo) MutateCooldownVsAiS(n int32) bool {
+	return rcv._tab.MutateInt32Slot(6, n)
+}
+
+func (rcv *AdsInfo) CooldownHintS() int32 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(8))
+	if o != 0 {
+		return rcv._tab.GetInt32(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *AdsInfo) MutateCooldownHintS(n int32) bool {
+	return rcv._tab.MutateInt32Slot(8, n)
+}
+
+func (rcv *AdsInfo) Suppressed() bool {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(10))
+	if o != 0 {
+		return rcv._tab.GetBool(o + rcv._tab.Pos)
+	}
+	return false
+}
+
+func (rcv *AdsInfo) MutateSuppressed(n bool) bool {
+	return rcv._tab.MutateBoolSlot(10, n)
+}
+
+func AdsInfoStart(builder *flatbuffers.Builder) {
+	builder.StartObject(4)
+}
+func AdsInfoAddCooldownGlobalS(builder *flatbuffers.Builder, cooldownGlobalS int32) {
+	builder.PrependInt32Slot(0, cooldownGlobalS, 0)
+}
+func AdsInfoAddCooldownVsAiS(builder *flatbuffers.Builder, cooldownVsAiS int32) {
+	builder.PrependInt32Slot(1, cooldownVsAiS, 0)
+}
+func AdsInfoAddCooldownHintS(builder *flatbuffers.Builder, cooldownHintS int32) {
+	builder.PrependInt32Slot(2, cooldownHintS, 0)
+}
+func AdsInfoAddSuppressed(builder *flatbuffers.Builder, suppressed bool) {
+	builder.PrependBoolSlot(3, suppressed, false)
+}
+func AdsInfoEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	return builder.EndObject()
+}

pkg/fbs/scrabblefb/Profile.go

@@ -231,8 +231,21 @@ func (rcv *Profile) DictVersionsLength() int {
 	return 0
 }
 
+func (rcv *Profile) Ads(obj *AdsInfo) *AdsInfo {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(38))
+	if o != 0 {
+		x := rcv._tab.Indirect(o + rcv._tab.Pos)
+		if obj == nil {
+			obj = new(AdsInfo)
+		}
+		obj.Init(rcv._tab.Bytes, x)
+		return obj
+	}
+	return nil
+}
+
 func ProfileStart(builder *flatbuffers.Builder) {
-	builder.StartObject(17)
+	builder.StartObject(18)
 }
 func ProfileAddUserId(builder *flatbuffers.Builder, userId flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(userId), 0)
@@ -291,6 +304,9 @@ func ProfileAddDictVersions(builder *flatbuffers.Builder, dictVersions flatbuffe
 func ProfileStartDictVersionsVector(builder *flatbuffers.Builder, numElems int) flatbuffers.UOffsetT {
 	return builder.StartVector(4, numElems, 4)
 }
+func ProfileAddAds(builder *flatbuffers.Builder, ads flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(17, flatbuffers.UOffsetT(ads), 0)
+}
 func ProfileEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
 	return builder.EndObject()
 }

ui/src/game/Game.svelte

@@ -15,6 +15,7 @@
   import { app, handleError, showToast, markChatRead, seedChatUnread } from '../lib/app.svelte';
   import { connection } from '../lib/connection.svelte';
   import { offlineMode } from '../lib/offline.svelte';
+  import { maybeShowInterstitial } from '../lib/ads';
   import { GatewayError } from '../lib/client';
   import { t, type MessageKey } from '../lib/i18n/index.svelte';
   import type { EvalResult, MoveRecord, MoveResult, StateView, Tile } from '../lib/model';
@@ -946,6 +947,12 @@
       if (view?.game.hotseat) await advanceHotseat();
       haptic('success');
       zoomed = false;
+      // A confirmed move may trigger a post-move interstitial (VK, frequency-gated, client-mirrored).
+      // Only submitPlay earns one — never a pass / exchange / resign. Fire-and-forget.
+      void maybeShowInterstitial(app.profile?.ads, 'move', {
+        vsAi: !!view?.game.vsAi,
+        online: connection.online && !offlineMode.active,
+      });
     } catch (e) {
       handleError(e);
     } finally {
@@ -1007,6 +1014,11 @@
     }
     try {
       const h = await source.hint(id);
+      // Applying a hint triggers its own post-move interstitial, independent of the move cooldown.
+      void maybeShowInterstitial(app.profile?.ads, 'hint', {
+        vsAi: !!view?.game.vsAi,
+        online: connection.online && !offlineMode.active,
+      });
       if (h.move.tiles.length && view) {
         placement = placementFromHint(h.move.tiles, view.rack);
         // Scroll the (zoomed) board to the hint's placement rather than the top-left:

ui/src/gen/fbs/scrabblefb.ts

@@ -4,6 +4,7 @@ export { AccountDeleteConfirm } from './scrabblefb/account-delete-confirm.js';
 export { AccountDeleteRequestResult } from './scrabblefb/account-delete-request-result.js';
 export { AccountRef } from './scrabblefb/account-ref.js';
 export { Ack } from './scrabblefb/ack.js';
+export { AdsInfo } from './scrabblefb/ads-info.js';
 export { AlphabetEntry } from './scrabblefb/alphabet-entry.js';
 export { BannerCampaign } from './scrabblefb/banner-campaign.js';
 export { BannerInfo } from './scrabblefb/banner-info.js';

ui/src/gen/fbs/scrabblefb/ads-info.ts

@@ -0,0 +1,76 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+export class AdsInfo {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+  __init(i:number, bb:flatbuffers.ByteBuffer):AdsInfo {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+static getRootAsAdsInfo(bb:flatbuffers.ByteBuffer, obj?:AdsInfo):AdsInfo {
+  return (obj || new AdsInfo()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+static getSizePrefixedRootAsAdsInfo(bb:flatbuffers.ByteBuffer, obj?:AdsInfo):AdsInfo {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new AdsInfo()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+cooldownGlobalS():number {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+cooldownVsAiS():number {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+cooldownHintS():number {
+  const offset = this.bb!.__offset(this.bb_pos, 8);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+suppressed():boolean {
+  const offset = this.bb!.__offset(this.bb_pos, 10);
+  return offset ? !!this.bb!.readInt8(this.bb_pos + offset) : false;
+}
+
+static startAdsInfo(builder:flatbuffers.Builder) {
+  builder.startObject(4);
+}
+
+static addCooldownGlobalS(builder:flatbuffers.Builder, cooldownGlobalS:number) {
+  builder.addFieldInt32(0, cooldownGlobalS, 0);
+}
+
+static addCooldownVsAiS(builder:flatbuffers.Builder, cooldownVsAiS:number) {
+  builder.addFieldInt32(1, cooldownVsAiS, 0);
+}
+
+static addCooldownHintS(builder:flatbuffers.Builder, cooldownHintS:number) {
+  builder.addFieldInt32(2, cooldownHintS, 0);
+}
+
+static addSuppressed(builder:flatbuffers.Builder, suppressed:boolean) {
+  builder.addFieldInt8(3, +suppressed, +false);
+}
+
+static endAdsInfo(builder:flatbuffers.Builder):flatbuffers.Offset {
+  const offset = builder.endObject();
+  return offset;
+}
+
+static createAdsInfo(builder:flatbuffers.Builder, cooldownGlobalS:number, cooldownVsAiS:number, cooldownHintS:number, suppressed:boolean):flatbuffers.Offset {
+  AdsInfo.startAdsInfo(builder);
+  AdsInfo.addCooldownGlobalS(builder, cooldownGlobalS);
+  AdsInfo.addCooldownVsAiS(builder, cooldownVsAiS);
+  AdsInfo.addCooldownHintS(builder, cooldownHintS);
+  AdsInfo.addSuppressed(builder, suppressed);
+  return AdsInfo.endAdsInfo(builder);
+}
+}

ui/src/gen/fbs/scrabblefb/profile.ts

@@ -2,6 +2,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
+import { AdsInfo } from '../scrabblefb/ads-info.js';
 import { BannerInfo } from '../scrabblefb/banner-info.js';
 import { DictVersion } from '../scrabblefb/dict-version.js';
 
@@ -135,8 +136,13 @@ dictVersionsLength():number {
   return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
 }
 
+ads(obj?:AdsInfo):AdsInfo|null {
+  const offset = this.bb!.__offset(this.bb_pos, 38);
+  return offset ? (obj || new AdsInfo()).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
+}
+
 static startProfile(builder:flatbuffers.Builder) {
-  builder.startObject(17);
+  builder.startObject(18);
 }
 
 static addUserId(builder:flatbuffers.Builder, userIdOffset:flatbuffers.Offset) {
@@ -231,6 +237,10 @@ static startDictVersionsVector(builder:flatbuffers.Builder, numElems:number) {
   builder.startVector(4, numElems, 4);
 }
 
+static addAds(builder:flatbuffers.Builder, adsOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(17, adsOffset, 0);
+}
+
 static endProfile(builder:flatbuffers.Builder):flatbuffers.Offset {
   const offset = builder.endObject();
   return offset;

ui/src/lib/ads.test.ts

@@ -0,0 +1,116 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import type { AdsConfig } from './model';
+
+// Mock ads.ts's three impure imports so the client-mirrored gate is observable without a VK
+// bridge, a wallet context or the Svelte toast store. ./model is type-only (erased).
+const mocks = vi.hoisted(() => ({
+  vkShowInterstitial: vi.fn(),
+  vkRewardedReady: vi.fn(),
+  vkShowRewarded: vi.fn(),
+  executionContext: vi.fn(),
+  showToast: vi.fn(),
+}));
+vi.mock('./vk', () => ({
+  vkShowInterstitial: mocks.vkShowInterstitial,
+  vkRewardedReady: mocks.vkRewardedReady,
+  vkShowRewarded: mocks.vkShowRewarded,
+}));
+vi.mock('./wallet', () => ({ executionContext: mocks.executionContext }));
+vi.mock('./app.svelte', () => ({ showToast: mocks.showToast }));
+
+import { maybeShowInterstitial } from './ads';
+
+const ADS: AdsConfig = { cooldownGlobalS: 300, cooldownVsAiS: 1800, cooldownHintS: 60, suppressed: false };
+const ONLINE = { vsAi: false, online: true };
+// A realistic epoch base: the never-shown last time is 0, so the first show needs now >> cooldown
+// (as with a real Date.now); anchoring at 0 would gate the very first call (now - 0 < cooldown).
+const BASE = 1_700_000_000_000;
+
+beforeEach(() => {
+  // A minimal in-memory localStorage (node has none) so the per-kind last-shown gate persists
+  // across calls within a test.
+  const store = new Map<string, string>();
+  (globalThis as unknown as { localStorage: Storage }).localStorage = {
+    getItem: (k: string) => store.get(k) ?? null,
+    setItem: (k: string, v: string) => void store.set(k, v),
+    removeItem: (k: string) => void store.delete(k),
+    clear: () => store.clear(),
+    key: () => null,
+    length: 0,
+  } as Storage;
+  vi.clearAllMocks();
+  vi.useFakeTimers();
+  vi.setSystemTime(BASE);
+  mocks.executionContext.mockReturnValue('vk');
+  mocks.vkShowInterstitial.mockResolvedValue(true);
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+  vi.unstubAllEnvs();
+});
+
+describe('maybeShowInterstitial (client-mirrored gate)', () => {
+  it('does not show when the config is absent', async () => {
+    expect(await maybeShowInterstitial(undefined, 'move', ONLINE)).toBe(false);
+    expect(mocks.vkShowInterstitial).not.toHaveBeenCalled();
+  });
+
+  it('does not show when suppressed (no-ads / no_banner)', async () => {
+    expect(await maybeShowInterstitial({ ...ADS, suppressed: true }, 'move', ONLINE)).toBe(false);
+    expect(mocks.showToast).not.toHaveBeenCalled();
+    expect(mocks.vkShowInterstitial).not.toHaveBeenCalled();
+  });
+
+  it('does not show when offline', async () => {
+    expect(await maybeShowInterstitial(ADS, 'move', { vsAi: false, online: false })).toBe(false);
+    expect(mocks.vkShowInterstitial).not.toHaveBeenCalled();
+  });
+
+  it('does not show outside VK (real ad path)', async () => {
+    mocks.executionContext.mockReturnValue('web');
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(false);
+    expect(mocks.vkShowInterstitial).not.toHaveBeenCalled();
+  });
+
+  it('shows a VK interstitial inside VK when the cooldown allows', async () => {
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(true);
+    expect(mocks.vkShowInterstitial).toHaveBeenCalledTimes(1);
+    expect(mocks.showToast).not.toHaveBeenCalled();
+  });
+
+  it('respects the per-kind cooldown: a second move within the window is gated', async () => {
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(true);
+    vi.setSystemTime(BASE + 299_000); // +299s < the 300s global cooldown
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(false);
+    vi.setSystemTime(BASE + 300_000); // the cooldown has now elapsed
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(true);
+    expect(mocks.vkShowInterstitial).toHaveBeenCalledTimes(2);
+  });
+
+  it('tracks move and hint cooldowns independently', async () => {
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(true);
+    // A hint right after a move still fires — a separate kind key with its own 60s cooldown.
+    expect(await maybeShowInterstitial(ADS, 'hint', ONLINE)).toBe(true);
+    vi.setSystemTime(BASE + 59_000); // +59s < the 60s hint cooldown
+    expect(await maybeShowInterstitial(ADS, 'hint', ONLINE)).toBe(false);
+    vi.setSystemTime(BASE + 60_000);
+    expect(await maybeShowInterstitial(ADS, 'hint', ONLINE)).toBe(true);
+  });
+
+  it('uses the longer vs_ai cooldown for a vs_ai move', async () => {
+    expect(await maybeShowInterstitial(ADS, 'move', { vsAi: true, online: true })).toBe(true);
+    vi.setSystemTime(BASE + 1_799_000); // +1799s < the 1800s vs_ai cooldown
+    expect(await maybeShowInterstitial(ADS, 'move', { vsAi: true, online: true })).toBe(false);
+    vi.setSystemTime(BASE + 1_800_000);
+    expect(await maybeShowInterstitial(ADS, 'move', { vsAi: true, online: true })).toBe(true);
+  });
+
+  it('shows the test-stub toast instead of a real ad when the stub flag is set', async () => {
+    vi.stubEnv('VITE_ADS_STUB', '1');
+    mocks.executionContext.mockReturnValue('web'); // the stub bypasses the VK gate
+    expect(await maybeShowInterstitial(ADS, 'move', ONLINE)).toBe(true);
+    expect(mocks.showToast).toHaveBeenCalledWith('ad fired');
+    expect(mocks.vkShowInterstitial).not.toHaveBeenCalled();
+  });
+});

ui/src/lib/ads.ts

@@ -4,7 +4,9 @@
 // flow is testable without waiting for a real ad — production never sets the flag, so a real ad that
 // fails to load there must not credit (no stub fallback in prod).
 import { executionContext } from './wallet';
-import { vkRewardedReady, vkShowRewarded } from './vk';
+import { vkRewardedReady, vkShowRewarded, vkShowInterstitial } from './vk';
+import { showToast } from './app.svelte';
+import type { AdsConfig } from './model';
 
 /**
  * adsStubEnabled reports the contour test stub (VITE_ADS_STUB=1). Production never sets it, so it
@@ -46,3 +48,55 @@ export async function showRewarded(): Promise<RewardedResult> {
   }
   return { watched: await vkShowRewarded(), stub: false };
 }
+
+// The post-move interstitial gate is client-mirrored: the server sends the cooldowns + suppressed in
+// the profile (Profile.ads); the client tracks the last-shown time per kind in localStorage and
+// self-gates. Last-shown is per-device (cleared with storage) — acceptable for a frequency gate.
+const INTERSTITIAL_LAST_KEY = 'ads.interstitial.last';
+
+// interstitialLast reads the last-shown epoch millis per kind (0 when absent/corrupt).
+function interstitialLast(): { move: number; hint: number } {
+  try {
+    const raw = localStorage.getItem(INTERSTITIAL_LAST_KEY);
+    if (raw) {
+      const j = JSON.parse(raw) as Partial<{ move: number; hint: number }>;
+      return { move: j.move ?? 0, hint: j.hint ?? 0 };
+    }
+  } catch {
+    /* a corrupt or unavailable store simply resets the gate */
+  }
+  return { move: 0, hint: 0 };
+}
+
+function recordInterstitial(kind: 'move' | 'hint', now: number): void {
+  try {
+    const l = interstitialLast();
+    l[kind] = now;
+    localStorage.setItem(INTERSTITIAL_LAST_KEY, JSON.stringify(l));
+  } catch {
+    /* ignore a write failure — the worst case is one extra ad next time */
+  }
+}
+
+/**
+ * maybeShowInterstitial shows a post-move (`kind='move'`, global / vs_ai cooldown) or post-hint
+ * (`kind='hint'`, its own short cooldown) interstitial when the client-mirrored gate allows: not
+ * suppressed (no-ads), online, inside VK (the stub bypasses VK), and the mirrored cooldown elapsed.
+ * The stub (contour test) shows an "ad fired" toast. Returns whether an ad was shown. Fire-and-forget
+ * — the caller does not await a result to proceed.
+ */
+export async function maybeShowInterstitial(
+  ads: AdsConfig | undefined,
+  kind: 'move' | 'hint',
+  opts: { vsAi: boolean; online: boolean },
+): Promise<boolean> {
+  if (!ads || ads.suppressed || !opts.online) return false;
+  const stub = adsStubEnabled();
+  if (!stub && executionContext() !== 'vk') return false;
+  const cooldownS = kind === 'hint' ? ads.cooldownHintS : opts.vsAi ? ads.cooldownVsAiS : ads.cooldownGlobalS;
+  const now = Date.now();
+  if (now - interstitialLast()[kind] < cooldownS * 1000) return false;
+  const shown = stub ? (showToast('ad fired'), true) : await vkShowInterstitial();
+  if (shown) recordInterstitial(kind, now);
+  return shown;
+}

ui/src/lib/codec.test.ts

@@ -814,6 +814,42 @@ describe('codec', () => {
     expect(decodeProfile(b.asUint8Array()).banner).toBeUndefined();
   });
 
+  it('decodes the profile interstitial-ad config', () => {
+    const b = new Builder(64);
+    const uid = b.createString('u-1');
+    const ads = fb.AdsInfo.createAdsInfo(b, 300, 1800, 60, false);
+    fb.Profile.startProfile(b);
+    fb.Profile.addUserId(b, uid);
+    fb.Profile.addAds(b, ads);
+    b.finish(fb.Profile.endProfile(b));
+    expect(decodeProfile(b.asUint8Array()).ads).toEqual({
+      cooldownGlobalS: 300,
+      cooldownVsAiS: 1800,
+      cooldownHintS: 60,
+      suppressed: false,
+    });
+  });
+
+  it('carries the suppressed flag through the ad config', () => {
+    const b = new Builder(64);
+    const uid = b.createString('u-1');
+    const ads = fb.AdsInfo.createAdsInfo(b, 300, 1800, 60, true);
+    fb.Profile.startProfile(b);
+    fb.Profile.addUserId(b, uid);
+    fb.Profile.addAds(b, ads);
+    b.finish(fb.Profile.endProfile(b));
+    expect(decodeProfile(b.asUint8Array()).ads?.suppressed).toBe(true);
+  });
+
+  it('leaves the profile ads undefined when absent', () => {
+    const b = new Builder(64);
+    const uid = b.createString('u-1');
+    fb.Profile.startProfile(b);
+    fb.Profile.addUserId(b, uid);
+    b.finish(fb.Profile.endProfile(b));
+    expect(decodeProfile(b.asUint8Array()).ads).toBeUndefined();
+  });
+
   it('decodes the profile variant preferences', () => {
     const b = new Builder(64);
     const uid = b.createString('u-1');

ui/src/lib/codec.ts

@@ -14,6 +14,7 @@ import type {
   RobotBlockEntry,
   RobotFriendRequestEntry,
   Banner,
+  AdsConfig,
   BannerCampaign,
   BestMove,
   BestMoveTile,
@@ -461,6 +462,7 @@ export function decodeProfile(buf: Uint8Array): Profile {
     notificationsInAppOnly: p.notificationsInAppOnly(),
     variantPreferences: decodeVariantPreferences(p),
     banner: decodeBanner(p),
+    ads: decodeAds(p),
     email: s(p.email()),
     telegramLinked: p.telegramLinked(),
     vkLinked: p.vkLinked(),
@@ -497,6 +499,19 @@ function bannerTriple(bg: string | null, fg: string | null, link: string | null)
   return bg && fg && link ? { bg, fg, link } : null;
 }
 
+// decodeAds projects the optional post-move interstitial config of a Profile, or undefined when
+// absent (an old backend); the client then shows no interstitial.
+function decodeAds(p: fb.Profile): AdsConfig | undefined {
+  const a = p.ads();
+  if (!a) return undefined;
+  return {
+    cooldownGlobalS: a.cooldownGlobalS(),
+    cooldownVsAiS: a.cooldownVsAiS(),
+    cooldownHintS: a.cooldownHintS(),
+    suppressed: a.suppressed(),
+  };
+}
+
 // decodeBanner projects the optional advertising-banner block of a Profile, or
 // undefined when the viewer is not eligible (the field is absent).
 function decodeBanner(p: fb.Profile): Banner | undefined {

ui/src/lib/mock/data.ts

@@ -45,6 +45,8 @@ export const PROFILE: Profile = {
   // Every variant's current dictionary version, as the backend advertises it on the profile —
   // the offline preloader targets `variant@version`.
   dictVersions: { erudit_ru: 'v1.3.0', scrabble_ru: 'v1.3.0', scrabble_en: 'v1.3.0' },
+  // Post-move interstitial config (short cooldowns so the mock stub is exercisable); not suppressed.
+  ads: { cooldownGlobalS: 300, cooldownVsAiS: 1800, cooldownHintS: 60, suppressed: false },
 };
 
 // Seed social/account data for the mock (pnpm start + Playwright). The mock profile

ui/src/lib/model.ts

@@ -226,6 +226,8 @@ export interface Profile {
   variantPreferences: Variant[];
   /** The advertising-banner block, present only for a viewer eligible to see it. */
   banner?: Banner;
+  /** The post-move interstitial-ad config for the client-mirrored gate (cooldowns + suppressed). */
+  ads?: AdsConfig;
   /** The account's confirmed email address ("" when none). */
   email: string;
   /** Whether a Telegram / VK identity is attached — drives the Add / Unlink controls. */
@@ -237,6 +239,15 @@ export interface Profile {
   dictVersions: Partial<Record<Variant, string>>;
 }
 
+/** The post-move interstitial-ad config for the client-mirrored gate: the cooldowns (seconds) and
+ *  whether ads are suppressed in the current context (a no-ads benefit here, or the no_banner role). */
+export interface AdsConfig {
+  cooldownGlobalS: number;
+  cooldownVsAiS: number;
+  cooldownHintS: number;
+  suppressed: boolean;
+}
+
 /** Banner is the advertising-banner block of an eligible viewer's profile. */
 export interface Banner {
   campaigns: BannerCampaign[];

ui/src/lib/vk.ts

@@ -225,6 +225,20 @@ export async function vkShowRewarded(): Promise<boolean> {
   }
 }
 
+/**
+ * vkShowInterstitial shows a between-screens interstitial ad (VKWebAppShowNativeAds, interstitial
+ * format) and reports whether it was shown. It carries no reward — it is the post-move fullscreen ad.
+ * A rejected or unavailable call reports false.
+ */
+export async function vkShowInterstitial(): Promise<boolean> {
+  try {
+    const data = await (await bridge()).send('VKWebAppShowNativeAds', { ad_format: 'interstitial' });
+    return !!(data as { result?: boolean }).result;
+  } catch {
+    return false;
+  }
+}
+
 /**
  * vkDownloadFile downloads url as filename through the VK client (VKWebAppDownloadFile) —
  * the mobile in-app file delivery, where the webview ignores <a download>. Resolves false