diff --git a/backend/internal/handler/grok_media.go b/backend/internal/handler/grok_media.go
index 408020f0a6..6b10f7bcbe 100644
--- a/backend/internal/handler/grok_media.go
+++ b/backend/internal/handler/grok_media.go
@@ -166,6 +166,7 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 	failedAccountIDs := make(map[int64]struct{})
 	sameAccountRetryCount := make(map[int64]int)
 	var lastFailoverErr *service.UpstreamFailoverError
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 	switchCount := 0
 	maxAccountSwitches := h.maxAccountSwitches
 	if maxAccountSwitches <= 0 {
@@ -300,6 +301,10 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 					return
 				}
 				switchCount++
+				if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
+					h.handleFailoverExhausted(c, failoverErr, false)
+					return
+				}
 				reqLog.Warn("grok_media.upstream_failover_switching",
 					zap.Int64("account_id", account.ID),
 					zap.Int("upstream_status", failoverErr.StatusCode),
diff --git a/backend/internal/handler/openai_alpha_search.go b/backend/internal/handler/openai_alpha_search.go
index a808145235..4f5c07d8c5 100644
--- a/backend/internal/handler/openai_alpha_search.go
+++ b/backend/internal/handler/openai_alpha_search.go
@@ -106,6 +106,7 @@ func (h *OpenAIGatewayHandler) AlphaSearch(c *gin.Context) {
 	failedAccountIDs := make(map[int64]struct{})
 	var lastFailoverErr *service.UpstreamFailoverError
 	switchCount := 0
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 	routingStart := time.Now()
 
 	for {
@@ -188,7 +189,7 @@ func (h *OpenAIGatewayHandler) AlphaSearch(c *gin.Context) {
 			return
 		}
 		switchCount++
-		if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+		if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 			h.handleFailoverExhausted(c, failoverErr, false)
 			return
 		}
diff --git a/backend/internal/handler/openai_chat_completions.go b/backend/internal/handler/openai_chat_completions.go
index fc58b3a25a..004aff2bb7 100644
--- a/backend/internal/handler/openai_chat_completions.go
+++ b/backend/internal/handler/openai_chat_completions.go
@@ -133,6 +133,7 @@ func (h *OpenAIGatewayHandler) ChatCompletions(c *gin.Context) {
 	failedAccountIDs := make(map[int64]struct{})
 	sameAccountRetryCount := make(map[int64]int)
 	var lastFailoverErr *service.UpstreamFailoverError
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 
 	for {
 		if c.Request.Context().Err() != nil {
@@ -275,7 +276,7 @@ func (h *OpenAIGatewayHandler) ChatCompletions(c *gin.Context) {
 						return
 					}
 					switchCount++
-					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 						h.handleFailoverExhausted(c, failoverErr, streamStarted)
 						return
 					}
diff --git a/backend/internal/handler/openai_gateway_credential_failover_loop_test.go b/backend/internal/handler/openai_gateway_credential_failover_loop_test.go
index e7030d9d2f..42a6bf6cd3 100644
--- a/backend/internal/handler/openai_gateway_credential_failover_loop_test.go
+++ b/backend/internal/handler/openai_gateway_credential_failover_loop_test.go
@@ -31,6 +31,7 @@ type grokCredentialHandlerRepo struct {
 	accounts       []service.Account
 	setErrorIDs    []int64
 	setTempIDs     []int64
+	rateLimitIDs   []int64
 	updateExtraIDs []int64
 	selectionCalls int
 	setErrorErr    error
@@ -108,6 +109,34 @@ func (r *grokCredentialHandlerRepo) SetTempUnschedulable(_ context.Context, id i
 	return nil
 }
 
+func (r *grokCredentialHandlerRepo) SetRateLimited(_ context.Context, id int64, resetAt time.Time) error {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.rateLimitIDs = append(r.rateLimitIDs, id)
+	for i := range r.accounts {
+		if r.accounts[i].ID != id {
+			continue
+		}
+		now := time.Now()
+		r.accounts[i].RateLimitedAt = &now
+		value := resetAt
+		r.accounts[i].RateLimitResetAt = &value
+	}
+	return nil
+}
+
+func (r *grokCredentialHandlerRepo) SetRateLimitedIfLater(ctx context.Context, id int64, resetAt time.Time) error {
+	r.mu.Lock()
+	for i := range r.accounts {
+		if r.accounts[i].ID == id && r.accounts[i].RateLimitResetAt != nil && !resetAt.After(*r.accounts[i].RateLimitResetAt) {
+			r.mu.Unlock()
+			return nil
+		}
+	}
+	r.mu.Unlock()
+	return r.SetRateLimited(ctx, id, resetAt)
+}
+
 func (r *grokCredentialHandlerRepo) SetGrokCredentialErrorIfMatch(
 	_ context.Context,
 	id int64,
@@ -204,6 +233,12 @@ func (r *grokCredentialHandlerRepo) selectorCalls() int {
 	return r.selectionCalls
 }
 
+func (r *grokCredentialHandlerRepo) rateLimitedAccountIDs() []int64 {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return append([]int64(nil), r.rateLimitIDs...)
+}
+
 type grokCredentialHandlerTokenCache struct {
 	service.GrokTokenCache
 	mu        sync.Mutex
@@ -282,6 +317,8 @@ type grokCredentialHandlerUpstream struct {
 	requestURLs   []string
 	authorization []string
 	failAccountID int64
+	rateLimitIDs  map[int64]bool
+	failureStatus map[int64]int
 	cancelRequest context.CancelFunc
 }
 
@@ -295,8 +332,27 @@ func (u *grokCredentialHandlerUpstream) Do(req *http.Request, _ string, accountI
 	u.requestURLs = append(u.requestURLs, req.URL.String())
 	u.authorization = append(u.authorization, req.Header.Get("Authorization"))
 	failAccountID := u.failAccountID
+	rateLimited := u.rateLimitIDs[accountID]
+	failureStatus := u.failureStatus[accountID]
 	cancelRequest := u.cancelRequest
 	u.mu.Unlock()
+	if rateLimited {
+		return &http.Response{
+			StatusCode: http.StatusTooManyRequests,
+			Header: http.Header{
+				"Content-Type": []string{"application/json"},
+				"Retry-After":  []string{"60"},
+			},
+			Body: io.NopCloser(bytes.NewBufferString(`{"error":{"message":"rate limited"}}`)),
+		}, nil
+	}
+	if failureStatus > 0 {
+		return &http.Response{
+			StatusCode: failureStatus,
+			Header:     http.Header{"Content-Type": []string{"application/json"}},
+			Body:       io.NopCloser(bytes.NewBufferString(`{"error":{"message":"upstream unavailable"}}`)),
+		}, nil
+	}
 	if accountID == failAccountID {
 		if cancelRequest != nil {
 			cancelRequest()
@@ -502,6 +558,115 @@ func TestResponsesCredentialFailoverLoop(t *testing.T) {
 	})
 }
 
+func TestResponsesGrok429FailoverIsBounded(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	t.Run("first rate limited account selects healthy account", func(t *testing.T) {
+		_, repo, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "first_429")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodPost, "/openai/v1/responses", bytes.NewBufferString(`{"model":"grok","input":"hello","stream":false}`))
+		req.Header.Set("Content-Type", "application/json")
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusOK, recorder.Code, recorder.Body.String())
+		require.Contains(t, recorder.Body.String(), "resp_healthy")
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+		require.Equal(t, []int64{801}, repo.rateLimitedAccountIDs())
+	})
+
+	t.Run("two rate limited accounts stop without sweeping the pool", func(t *testing.T) {
+		_, repo, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "all_429")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodPost, "/openai/v1/responses", bytes.NewBufferString(`{"model":"grok","input":"hello","stream":false}`))
+		req.Header.Set("Content-Type", "application/json")
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusTooManyRequests, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+		require.Equal(t, []int64{801, 802}, repo.rateLimitedAccountIDs())
+		require.NotContains(t, recorder.Body.String(), "expired")
+		require.NotContains(t, recorder.Body.String(), "healthy-access")
+		require.NotContains(t, recorder.Body.String(), "rate limited")
+	})
+}
+
+func TestResponsesGrok429FailoverHandlesMixedStatuses(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	t.Run("429 then 500 stops after the bounded followup", func(t *testing.T) {
+		_, _, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "mixed_429_500")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodPost, "/openai/v1/responses", bytes.NewBufferString(`{"model":"grok","input":"hello","stream":false}`))
+		req.Header.Set("Content-Type", "application/json")
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusBadGateway, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+		require.NotContains(t, recorder.Body.String(), "upstream unavailable")
+	})
+
+	t.Run("500 then 429 permits one healthy followup", func(t *testing.T) {
+		_, _, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "mixed_500_429")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodPost, "/openai/v1/responses", bytes.NewBufferString(`{"model":"grok","input":"hello","stream":false}`))
+		req.Header.Set("Content-Type", "application/json")
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusOK, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802, 803}, upstream.accountHits())
+	})
+
+	t.Run("OAuth 429 then API-key failure cannot bypass the bound", func(t *testing.T) {
+		_, _, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "oauth_429_apikey_500")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodPost, "/openai/v1/responses", bytes.NewBufferString(`{"model":"grok","input":"hello","stream":false}`))
+		req.Header.Set("Content-Type", "application/json")
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusBadGateway, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+	})
+}
+
+func TestGrokMedia429FailoverIsBounded(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	t.Run("first 429 selects one healthy followup", func(t *testing.T) {
+		_, _, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "first_429")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodGet, "/openai/v1/videos/request-1", nil)
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusOK, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+	})
+
+	t.Run("second 429 stops without sweeping a third account", func(t *testing.T) {
+		_, _, upstream, router, cleanup := newGrokCredentialFailoverHandler(t, "all_429")
+		defer cleanup()
+		recorder := httptest.NewRecorder()
+		req := httptest.NewRequest(http.MethodGet, "/openai/v1/videos/request-1", nil)
+
+		router.ServeHTTP(recorder, req)
+
+		require.Equal(t, http.StatusTooManyRequests, recorder.Code, recorder.Body.String())
+		require.Equal(t, []int64{801, 802}, upstream.accountHits())
+		require.NotContains(t, recorder.Body.String(), "rate limited")
+	})
+}
+
 func TestGrokOAuthCredentialFailoverAcrossHTTPHandlers(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 	endpoints := []struct {
@@ -667,9 +832,23 @@ func newGrokCredentialFailoverHandler(t *testing.T, mode string) (*OpenAIGateway
 			},
 		},
 	}
-	if mode == "postmap_cancel" {
+	if mode == "postmap_cancel" || mode == "first_429" || mode == "all_429" || mode == "mixed_429_500" || mode == "mixed_500_429" || mode == "oauth_429_apikey_500" {
 		accounts[0].Credentials["expires_at"] = time.Now().Add(2 * time.Hour).UTC().Format(time.RFC3339)
 	}
+	if mode == "all_429" || mode == "mixed_429_500" || mode == "mixed_500_429" || mode == "oauth_429_apikey_500" {
+		accounts = append(accounts, service.Account{
+			ID: 803, Name: "untried-healthy", Platform: service.PlatformGrok, Type: service.AccountTypeOAuth,
+			Status: service.StatusActive, Schedulable: true, Concurrency: 1, Priority: 3,
+			Credentials: map[string]any{
+				"access_token": "untried-healthy-access", "refresh_token": "untried-healthy-refresh",
+				"expires_at": time.Now().Add(2 * time.Hour).UTC().Format(time.RFC3339),
+			},
+		})
+	}
+	if mode == "oauth_429_apikey_500" {
+		accounts[1].Type = service.AccountTypeAPIKey
+		accounts[1].Credentials = map[string]any{"api_key": "third-party-key"}
+	}
 	if mode == "all_revoked" {
 		accounts[1].Credentials["expires_at"] = time.Now().Add(-time.Minute).UTC().Format(time.RFC3339)
 	}
@@ -694,6 +873,21 @@ func newGrokCredentialFailoverHandler(t *testing.T, mode string) (*OpenAIGateway
 		provider.SetRefreshAPI(service.NewOAuthRefreshAPI(repo, tokenCache), refresher)
 	}
 	upstream := &grokCredentialHandlerUpstream{}
+	switch mode {
+	case "first_429":
+		upstream.rateLimitIDs = map[int64]bool{801: true}
+	case "all_429":
+		upstream.rateLimitIDs = map[int64]bool{801: true, 802: true}
+	case "mixed_429_500":
+		upstream.rateLimitIDs = map[int64]bool{801: true}
+		upstream.failureStatus = map[int64]int{802: http.StatusInternalServerError}
+	case "mixed_500_429":
+		upstream.failureStatus = map[int64]int{801: http.StatusInternalServerError}
+		upstream.rateLimitIDs = map[int64]bool{802: true}
+	case "oauth_429_apikey_500":
+		upstream.rateLimitIDs = map[int64]bool{801: true}
+		upstream.failureStatus = map[int64]int{802: http.StatusInternalServerError}
+	}
 	cfg := &config.Config{RunMode: config.RunModeSimple}
 	cfg.Gateway.MaxAccountSwitches = 3
 	billingCache := service.NewBillingCacheService(nil, nil, nil, nil, nil, nil, cfg, nil)
diff --git a/backend/internal/handler/openai_gateway_handler.go b/backend/internal/handler/openai_gateway_handler.go
index 6db72c270b..33bef42cef 100644
--- a/backend/internal/handler/openai_gateway_handler.go
+++ b/backend/internal/handler/openai_gateway_handler.go
@@ -332,6 +332,7 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 	failedAccountIDs := make(map[int64]struct{})
 	sameAccountRetryCount := make(map[int64]int)
 	var lastFailoverErr *service.UpstreamFailoverError
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 
 	for {
 		if c.Request.Context().Err() != nil {
@@ -487,7 +488,7 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 						return
 					}
 					switchCount++
-					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 						h.handleFailoverExhausted(c, failoverErr, streamStarted)
 						return
 					}
@@ -844,6 +845,7 @@ func (h *OpenAIGatewayHandler) Messages(c *gin.Context) {
 	failedAccountIDs := make(map[int64]struct{})
 	sameAccountRetryCount := make(map[int64]int)
 	var lastFailoverErr *service.UpstreamFailoverError
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 	effectiveMappedModel := preferredMappedModel
 
 	for {
@@ -991,7 +993,7 @@ func (h *OpenAIGatewayHandler) Messages(c *gin.Context) {
 						return
 					}
 					switchCount++
-					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 						h.handleAnthropicFailoverExhausted(c, failoverErr, streamStarted)
 						return
 					}
@@ -1496,6 +1498,7 @@ func (h *OpenAIGatewayHandler) ResponsesWebSocket(c *gin.Context) {
 	switchCount := 0
 	failedAccountIDs := make(map[int64]struct{})
 	var lastFailoverErr *service.UpstreamFailoverError
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 	handleWSFailover := func(account *service.Account, failoverErr *service.UpstreamFailoverError) bool {
 		if ctx.Err() != nil {
 			return false
@@ -1519,7 +1522,7 @@ func (h *OpenAIGatewayHandler) ResponsesWebSocket(c *gin.Context) {
 			return false
 		}
 		switchCount++
-		if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+		if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 			closeOpenAIWSFailoverExhausted(wsConn, failoverErr)
 			return false
 		}
diff --git a/backend/internal/handler/openai_images.go b/backend/internal/handler/openai_images.go
index c5982fb7d1..d18af28966 100644
--- a/backend/internal/handler/openai_images.go
+++ b/backend/internal/handler/openai_images.go
@@ -145,6 +145,7 @@ func (h *OpenAIGatewayHandler) Images(c *gin.Context) {
 	stopJSONKeepalive := func() {}
 	jsonKeepaliveStarted := false
 	defer func() { stopJSONKeepalive() }()
+	var oauth429FailoverState service.OpenAIOAuth429FailoverState
 
 	for {
 		reqLog.Debug("openai.images.account_selecting", zap.Int("excluded_account_count", len(failedAccountIDs)))
@@ -299,7 +300,7 @@ func (h *OpenAIGatewayHandler) Images(c *gin.Context) {
 						return
 					}
 					switchCount++
-					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount) {
+					if h.gatewayService.ShouldStopOpenAIOAuth429Failover(account, failoverErr.StatusCode, switchCount, &oauth429FailoverState) {
 						h.handleFailoverExhausted(c, failoverErr, streamStarted)
 						return
 					}
diff --git a/backend/internal/pkg/xai/oauth.go b/backend/internal/pkg/xai/oauth.go
index a8a549c9dc..ea837fd78a 100644
--- a/backend/internal/pkg/xai/oauth.go
+++ b/backend/internal/pkg/xai/oauth.go
@@ -5,6 +5,7 @@ import (
 	"crypto/sha256"
 	"encoding/base64"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"net/url"
 	"os"
@@ -164,6 +165,24 @@ func ValidatedBaseURL(override string) (string, error) {
 	return ValidateBaseURL(EffectiveBaseURL(override))
 }
 
+// BaseURLValidator applies the caller's outbound URL trust policy before xAI
+// endpoint paths are appended. The service layer uses this for API-key accounts
+// so the global security.url_allowlist policy remains the single source of
+// truth; OAuth callers keep using the strict trusted-host validator.
+type BaseURLValidator func(string) (string, error)
+
+func validatedBaseURLWithValidator(override string, validator BaseURLValidator) (string, error) {
+	if validator == nil {
+		return ValidatedBaseURL(override)
+	}
+	raw := EffectiveBaseURL(override)
+	validated, err := validator(raw)
+	if err != nil {
+		return "", err
+	}
+	return normalizeKnownBaseURLPath(validated)
+}
+
 type RuntimeSanityCheck struct {
 	Value     string `json:"value"`
 	Valid     bool   `json:"valid"`
@@ -282,7 +301,16 @@ func ValidateTrustedBaseURL(raw string) (string, error) {
 func normalizeKnownBaseURLPath(raw string) (string, error) {
 	parsed, err := url.Parse(raw)
 	if err != nil || parsed.Scheme == "" || parsed.Host == "" {
-		return "", fmt.Errorf("invalid url: %s", raw)
+		return "", errors.New("invalid base URL")
+	}
+	if parsed.User != nil {
+		return "", errors.New("base URL must not include userinfo")
+	}
+	if parsed.RawQuery != "" {
+		return "", errors.New("base URL must not include a query")
+	}
+	if parsed.Fragment != "" {
+		return "", errors.New("base URL must not include a fragment")
 	}
 	path := strings.TrimRight(parsed.Path, "/")
 	if path == "" {
@@ -435,7 +463,11 @@ func ParseAuthorizationInput(raw string) AuthorizationInput {
 }
 
 func BuildResponsesURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildResponsesURLWithValidator(baseURL, nil)
+}
+
+func BuildResponsesURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -443,7 +475,11 @@ func BuildResponsesURL(baseURL string) (string, error) {
 }
 
 func BuildChatCompletionsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildChatCompletionsURLWithValidator(baseURL, nil)
+}
+
+func BuildChatCompletionsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -451,7 +487,11 @@ func BuildChatCompletionsURL(baseURL string) (string, error) {
 }
 
 func BuildImagesGenerationsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildImagesGenerationsURLWithValidator(baseURL, nil)
+}
+
+func BuildImagesGenerationsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -459,7 +499,11 @@ func BuildImagesGenerationsURL(baseURL string) (string, error) {
 }
 
 func BuildImagesEditsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildImagesEditsURLWithValidator(baseURL, nil)
+}
+
+func BuildImagesEditsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -467,7 +511,11 @@ func BuildImagesEditsURL(baseURL string) (string, error) {
 }
 
 func BuildVideosGenerationsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildVideosGenerationsURLWithValidator(baseURL, nil)
+}
+
+func BuildVideosGenerationsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -475,7 +523,11 @@ func BuildVideosGenerationsURL(baseURL string) (string, error) {
 }
 
 func BuildVideosEditsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildVideosEditsURLWithValidator(baseURL, nil)
+}
+
+func BuildVideosEditsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -483,7 +535,11 @@ func BuildVideosEditsURL(baseURL string) (string, error) {
 }
 
 func BuildVideosExtensionsURL(baseURL string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildVideosExtensionsURLWithValidator(baseURL, nil)
+}
+
+func BuildVideosExtensionsURLWithValidator(baseURL string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
@@ -491,7 +547,11 @@ func BuildVideosExtensionsURL(baseURL string) (string, error) {
 }
 
 func BuildVideoURL(baseURL, requestID string) (string, error) {
-	validatedBaseURL, err := ValidatedBaseURL(baseURL)
+	return BuildVideoURLWithValidator(baseURL, requestID, nil)
+}
+
+func BuildVideoURLWithValidator(baseURL, requestID string, validator BaseURLValidator) (string, error) {
+	validatedBaseURL, err := validatedBaseURLWithValidator(baseURL, validator)
 	if err != nil {
 		return "", fmt.Errorf("invalid base url: %w", err)
 	}
diff --git a/backend/internal/pkg/xai/oauth_test.go b/backend/internal/pkg/xai/oauth_test.go
index 39200ffc39..a82a26e299 100644
--- a/backend/internal/pkg/xai/oauth_test.go
+++ b/backend/internal/pkg/xai/oauth_test.go
@@ -6,6 +6,7 @@ import (
 	"net/url"
 	"testing"
 
+	"github.com/Wei-Shaw/sub2api/internal/util/urlvalidator"
 	"github.com/stretchr/testify/require"
 )
 
@@ -165,6 +166,44 @@ func TestValidateBaseURLAllowsPublicThirdPartyGrokAPI(t *testing.T) {
 	require.Error(t, err)
 }
 
+func TestBuildResponsesURLWithValidatorUsesCallerPolicy(t *testing.T) {
+	validator := func(raw string) (string, error) {
+		return urlvalidator.ValidateURLFormat(raw, true)
+	}
+
+	target, err := BuildResponsesURLWithValidator("http://grok.example.test/v1/", validator)
+	require.NoError(t, err)
+	require.Equal(t, "http://grok.example.test/v1/responses", target)
+}
+
+func TestBuildResponsesURLPreservesUnsafeOverrideCustomPath(t *testing.T) {
+	t.Setenv(EnvAllowUnsafeURLOverrides, "true")
+
+	target, err := BuildResponsesURL("http://localhost:8080/custom")
+	require.NoError(t, err)
+	require.Equal(t, "http://localhost:8080/custom/responses", target)
+}
+
+func TestBuildResponsesURLWithValidatorRejectsBaseURLComponents(t *testing.T) {
+	permissive := func(raw string) (string, error) { return raw, nil }
+	tests := []struct {
+		name string
+		raw  string
+	}{
+		{name: "userinfo", raw: "https://user:secret@grok.example.test/v1"},
+		{name: "query", raw: "https://grok.example.test/v1?token=secret"},
+		{name: "fragment", raw: "https://grok.example.test/v1#secret"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := BuildResponsesURLWithValidator(tt.raw, permissive)
+			require.Error(t, err)
+			require.NotContains(t, err.Error(), "secret")
+		})
+	}
+}
+
 func TestValidateXAIURLsAllowUnsafeDevOverride(t *testing.T) {
 	t.Setenv(EnvAllowUnsafeURLOverrides, "true")
 
diff --git a/backend/internal/repository/account_repo.go b/backend/internal/repository/account_repo.go
index a3eba2eaa9..8527b7010d 100644
--- a/backend/internal/repository/account_repo.go
+++ b/backend/internal/repository/account_repo.go
@@ -1377,6 +1377,35 @@ func (r *accountRepository) SetRateLimitedIfLater(ctx context.Context, id int64,
 	return nil
 }
 
+// ClearRateLimitIfObserved clears exactly the Grok rate-limit generation seen
+// by a successful request. Matching both timestamps prevents a stale success
+// from erasing a later clear/re-arm generation with an equal or shorter reset.
+func (r *accountRepository) ClearRateLimitIfObserved(ctx context.Context, id int64, observedLimitedAt, observedResetAt time.Time) (bool, error) {
+	updated, err := r.client.Account.Update().
+		Where(
+			dbaccount.IDEQ(id),
+			dbaccount.PlatformEQ(service.PlatformGrok),
+			dbaccount.TypeEQ(service.AccountTypeOAuth),
+			dbaccount.RateLimitedAtEQ(observedLimitedAt),
+			dbaccount.RateLimitResetAtEQ(observedResetAt),
+		).
+		ClearRateLimitedAt().
+		ClearRateLimitResetAt().
+		Save(ctx)
+	if err != nil {
+		return false, err
+	}
+	if updated == 0 {
+		r.syncSchedulerAccountSnapshot(ctx, id)
+		return false, nil
+	}
+	if err := enqueueSchedulerOutbox(ctx, r.sql, service.SchedulerOutboxEventAccountChanged, &id, nil, nil); err != nil {
+		logger.LegacyPrintf("repository.account", "[SchedulerOutbox] enqueue observed rate-limit clear failed: account=%d err=%v", id, err)
+	}
+	r.syncSchedulerAccountSnapshot(ctx, id)
+	return true, nil
+}
+
 func (r *accountRepository) SetModelRateLimit(ctx context.Context, id int64, scope string, resetAt time.Time, reason ...string) error {
 	if scope == "" {
 		return nil
diff --git a/backend/internal/repository/account_repo_integration_test.go b/backend/internal/repository/account_repo_integration_test.go
index f82ad4ca28..ae519f3df4 100644
--- a/backend/internal/repository/account_repo_integration_test.go
+++ b/backend/internal/repository/account_repo_integration_test.go
@@ -722,6 +722,56 @@ func (s *AccountRepoSuite) TestSetRateLimitedIfLaterDoesNotShortenReset() {
 	s.Require().WithinDuration(later, *cacheRecorder.setAccounts[1].RateLimitResetAt, time.Second)
 }
 
+func (s *AccountRepoSuite) TestClearRateLimitIfObservedProtectsRearmed429Generation() {
+	account := mustCreateAccount(s.T(), s.client, &service.Account{
+		Name:     "acc-rl-conditional-clear",
+		Platform: service.PlatformGrok,
+		Type:     service.AccountTypeOAuth,
+	})
+	firstReset := time.Now().Add(30 * time.Minute).UTC().Truncate(time.Second)
+	rearmedReset := time.Now().Add(5 * time.Minute).UTC().Truncate(time.Second)
+
+	s.Require().NoError(s.repo.SetRateLimitedIfLater(s.ctx, account.ID, firstReset))
+	staleGeneration, err := s.repo.GetByID(s.ctx, account.ID)
+	s.Require().NoError(err)
+	s.Require().NotNil(staleGeneration.RateLimitedAt)
+	s.Require().NotNil(staleGeneration.RateLimitResetAt)
+	cleared, err := s.repo.ClearRateLimitIfObserved(s.ctx, account.ID, *staleGeneration.RateLimitedAt, *staleGeneration.RateLimitResetAt)
+	s.Require().NoError(err)
+	s.Require().True(cleared)
+
+	// A newer generation may legitimately re-arm a shorter boundary after the
+	// first generation was cleared. The stale success must not erase it.
+	s.Require().NoError(s.repo.SetRateLimitedIfLater(s.ctx, account.ID, rearmedReset))
+	cleared, err = s.repo.ClearRateLimitIfObserved(s.ctx, account.ID, *staleGeneration.RateLimitedAt, *staleGeneration.RateLimitResetAt)
+	s.Require().NoError(err)
+	s.Require().False(cleared)
+
+	got, err := s.repo.GetByID(s.ctx, account.ID)
+	s.Require().NoError(err)
+	s.Require().NotNil(got.RateLimitedAt)
+	s.Require().NotNil(got.RateLimitResetAt)
+	s.Require().WithinDuration(rearmedReset, *got.RateLimitResetAt, time.Second)
+
+	// An admin can retype the row while the successful OAuth request is still
+	// in flight. The stale OAuth recovery must not cross into API-key state even
+	// when both observed timestamps still match.
+	_, err = s.client.Account.UpdateOneID(account.ID).
+		SetType(service.AccountTypeAPIKey).
+		Save(s.ctx)
+	s.Require().NoError(err)
+	cleared, err = s.repo.ClearRateLimitIfObserved(s.ctx, account.ID, *got.RateLimitedAt, *got.RateLimitResetAt)
+	s.Require().NoError(err)
+	s.Require().False(cleared)
+
+	retyped, err := s.repo.GetByID(s.ctx, account.ID)
+	s.Require().NoError(err)
+	s.Require().Equal(service.AccountTypeAPIKey, retyped.Type)
+	s.Require().NotNil(retyped.RateLimitedAt)
+	s.Require().NotNil(retyped.RateLimitResetAt)
+	s.Require().WithinDuration(rearmedReset, *retyped.RateLimitResetAt, time.Second)
+}
+
 func (s *AccountRepoSuite) TestClearRateLimit() {
 	account := mustCreateAccount(s.T(), s.client, &service.Account{Name: "acc-clear"})
 	until := time.Now().Add(1 * time.Hour)
diff --git a/backend/internal/service/account_test_service.go b/backend/internal/service/account_test_service.go
index a9eef998e4..a739bcc120 100644
--- a/backend/internal/service/account_test_service.go
+++ b/backend/internal/service/account_test_service.go
@@ -695,7 +695,7 @@ func (s *AccountTestService) testGrokAccountConnection(c *gin.Context, account *
 		return s.sendErrorAndEnd(c, fmt.Sprintf("Unsupported Grok account type: %s", account.Type))
 	}
 
-	apiURL, err := xai.BuildResponsesURL(account.GetGrokBaseURL())
+	apiURL, err := buildGrokResponsesURL(account, s.cfg)
 	if err != nil {
 		return s.sendErrorAndEnd(c, fmt.Sprintf("Invalid Grok base URL: %s", err.Error()))
 	}
@@ -742,7 +742,7 @@ func (s *AccountTestService) testGrokAccountConnection(c *gin.Context, account *
 	now := time.Now()
 	snapshot := parseGrokQuotaSnapshot(resp.Header, resp.StatusCode, now)
 	if snapshot != nil && s.accountRepo != nil {
-		resetAt, limited := grokRateLimitResetAt(snapshot, now)
+		resetAt, limited := grokRateLimitResetAtForAccount(account, snapshot, now)
 		if limited {
 			normalizeGrokExhaustedWindowResets(snapshot, resetAt, now)
 		}
@@ -751,7 +751,11 @@ func (s *AccountTestService) testGrokAccountConnection(c *gin.Context, account *
 		})
 		if limited {
 			persistGrokRateLimit(ctx, s.accountRepo, account, resetAt)
+		} else if isSuccessfulGrokRateLimitRecovery(account, snapshot) {
+			clearGrokRateLimitAfterRecovery(ctx, s.accountRepo, account)
 		}
+	} else if s.accountRepo != nil && isSuccessfulGrokRateLimitRecovery(account, &xai.QuotaSnapshot{StatusCode: resp.StatusCode}) {
+		clearGrokRateLimitAfterRecovery(ctx, s.accountRepo, account)
 	}
 
 	if resp.StatusCode != http.StatusOK {
diff --git a/backend/internal/service/grok_media.go b/backend/internal/service/grok_media.go
index 5cc8e2d05e..f7c6bd8153 100644
--- a/backend/internal/service/grok_media.go
+++ b/backend/internal/service/grok_media.go
@@ -13,7 +13,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/Wei-Shaw/sub2api/internal/util/responseheaders"
 	"github.com/gin-gonic/gin"
 	"github.com/tidwall/gjson"
@@ -268,25 +267,6 @@ func (s *OpenAIGatewayService) BindGrokMediaVideoRequestAccount(ctx context.Cont
 	return s.BindStickySession(ctx, groupID, GrokMediaVideoRequestSessionHash(requestID), accountID)
 }
 
-func (e GrokMediaEndpoint) upstreamURL(baseURL, requestID string) (string, error) {
-	switch e {
-	case GrokMediaEndpointImagesGenerations:
-		return xai.BuildImagesGenerationsURL(baseURL)
-	case GrokMediaEndpointImagesEdits:
-		return xai.BuildImagesEditsURL(baseURL)
-	case GrokMediaEndpointVideosGenerations:
-		return xai.BuildVideosGenerationsURL(baseURL)
-	case GrokMediaEndpointVideosEdits:
-		return xai.BuildVideosEditsURL(baseURL)
-	case GrokMediaEndpointVideosExtensions:
-		return xai.BuildVideosExtensionsURL(baseURL)
-	case GrokMediaEndpointVideoStatus:
-		return xai.BuildVideoURL(baseURL, requestID)
-	default:
-		return "", fmt.Errorf("unsupported grok media endpoint: %s", e)
-	}
-}
-
 func (s *OpenAIGatewayService) ForwardGrokMedia(
 	ctx context.Context,
 	c *gin.Context,
@@ -308,7 +288,7 @@ func (s *OpenAIGatewayService) ForwardGrokMedia(
 	if err != nil {
 		return nil, err
 	}
-	targetURL, err := endpoint.upstreamURL(account.GetGrokMediaBaseURL(), requestID)
+	targetURL, err := buildGrokMediaURL(account, s.cfg, endpoint, requestID)
 	if err != nil {
 		return nil, err
 	}
@@ -368,7 +348,7 @@ func (s *OpenAIGatewayService) ForwardGrokMedia(
 		return s.handleGrokMediaErrorResponse(ctx, resp, c, account, requestIDHeader, requestModel)
 	}
 
-	s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+	s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 	respBody, err := ReadUpstreamResponseBody(resp.Body, s.cfg, c, openAITooLargeError)
 	if err != nil {
 		return nil, err
diff --git a/backend/internal/service/grok_quota_service.go b/backend/internal/service/grok_quota_service.go
index ef8e3e4c03..a95b778707 100644
--- a/backend/internal/service/grok_quota_service.go
+++ b/backend/internal/service/grok_quota_service.go
@@ -135,7 +135,7 @@ func (s *GrokQuotaService) probeUsage(ctx context.Context, accountID int64) (*Gr
 	if err != nil {
 		return nil, infraerrors.Newf(http.StatusBadRequest, "GROK_QUOTA_PROBE_BODY_ERROR", "failed to build probe body: %v", err)
 	}
-	targetURL, err := xai.BuildResponsesURL(account.GetGrokBaseURL())
+	targetURL, err := buildGrokResponsesURL(account, nil)
 	if err != nil {
 		return nil, infraerrors.Newf(http.StatusBadRequest, "GROK_QUOTA_BASE_URL_INVALID", "invalid Grok base_url: %v", err)
 	}
@@ -160,7 +160,7 @@ func (s *GrokQuotaService) probeUsage(ctx context.Context, accountID int64) (*Gr
 	defer func() { _ = resp.Body.Close() }()
 
 	snapshot := xai.ObserveQuotaHeaders(resp.Header, resp.StatusCode, "active_probe")
-	resetAt, limited := grokRateLimitResetAt(snapshot, time.Now())
+	resetAt, limited := grokRateLimitResetAtForAccount(account, snapshot, time.Now())
 	if limited {
 		normalizeGrokExhaustedWindowResets(snapshot, resetAt, time.Now())
 	}
@@ -169,6 +169,8 @@ func (s *GrokQuotaService) probeUsage(ctx context.Context, accountID int64) (*Gr
 	})
 	if limited {
 		persistGrokRateLimit(ctx, s.accountRepo, account, resetAt)
+	} else if isSuccessfulGrokRateLimitRecovery(account, snapshot) {
+		clearGrokRateLimitAfterRecovery(ctx, s.accountRepo, account)
 	}
 
 	result := &GrokQuotaProbeResult{
diff --git a/backend/internal/service/grok_quota_service_test.go b/backend/internal/service/grok_quota_service_test.go
index 4e06fe156c..ad3c85ba19 100644
--- a/backend/internal/service/grok_quota_service_test.go
+++ b/backend/internal/service/grok_quota_service_test.go
@@ -32,6 +32,10 @@ type grokQuotaAccountRepo struct {
 	lastTempUnschedID     int64
 	lastTempUnschedUntil  time.Time
 	lastTempUnschedReason string
+	recoveryClearCalls    int
+	recoveryObservedAt    time.Time
+	recoveryObservedReset time.Time
+	recoveryClearResult   bool
 }
 
 func (r *grokQuotaAccountRepo) UpdateExtra(_ context.Context, id int64, updates map[string]any) error {
@@ -54,6 +58,13 @@ func (r *grokQuotaAccountRepo) SetRateLimitedIfLater(ctx context.Context, id int
 	return r.SetRateLimited(ctx, id, resetAt)
 }
 
+func (r *grokQuotaAccountRepo) ClearRateLimitIfObserved(_ context.Context, _ int64, observedLimitedAt, observedResetAt time.Time) (bool, error) {
+	r.recoveryClearCalls++
+	r.recoveryObservedAt = observedLimitedAt
+	r.recoveryObservedReset = observedResetAt
+	return r.recoveryClearResult, nil
+}
+
 func (r *grokQuotaAccountRepo) SetTempUnschedulable(_ context.Context, id int64, until time.Time, reason string) error {
 	r.tempUnschedCalls++
 	r.lastTempUnschedID = id
@@ -375,10 +386,15 @@ func TestGrokQuotaServiceProbeUsageStoresNoHeadersState(t *testing.T) {
 	t.Parallel()
 
 	account := healthyGrokQuotaOAuthAccount(45)
+	observedResetAt := time.Now().Add(-time.Second).UTC().Truncate(time.Second)
+	observedLimitedAt := observedResetAt.Add(-grokRateLimitRepeatCooldown)
+	account.RateLimitedAt = &observedLimitedAt
+	account.RateLimitResetAt = &observedResetAt
 	repo := &grokQuotaAccountRepo{
 		mockAccountRepoForPlatform: &mockAccountRepoForPlatform{
 			accountsByID: map[int64]*Account{45: account},
 		},
+		recoveryClearResult: true,
 	}
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
@@ -401,6 +417,9 @@ func TestGrokQuotaServiceProbeUsageStoresNoHeadersState(t *testing.T) {
 	require.True(t, ok)
 	require.False(t, stored.HeadersObserved)
 	require.Equal(t, http.StatusOK, stored.StatusCode)
+	require.Equal(t, 1, repo.recoveryClearCalls)
+	require.Equal(t, observedLimitedAt, repo.recoveryObservedAt)
+	require.Equal(t, observedResetAt, repo.recoveryObservedReset)
 }
 
 func TestGrokQuotaServiceProbeUsageReturnsRateLimitedSnapshot(t *testing.T) {
diff --git a/backend/internal/service/grok_upstream_url.go b/backend/internal/service/grok_upstream_url.go
new file mode 100644
index 0000000000..ca2ba6b64d
--- /dev/null
+++ b/backend/internal/service/grok_upstream_url.go
@@ -0,0 +1,90 @@
+package service
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
+	"github.com/Wei-Shaw/sub2api/internal/util/urlvalidator"
+)
+
+func grokBaseURLValidator(account *Account, cfg *config.Config) (xai.BaseURLValidator, error) {
+	if account == nil || !account.IsGrok() {
+		return nil, fmt.Errorf("grok account is required")
+	}
+	switch account.Type {
+	case AccountTypeOAuth:
+		// Subscription credentials are never governed by the operator's API-key
+		// URL policy. They stay pinned to the supported CLI gateway.
+		return redactedGrokBaseURLValidator(xai.ValidateTrustedBaseURL), nil
+	case AccountTypeAPIKey:
+		if cfg == nil {
+			return redactedGrokBaseURLValidator(xai.ValidateBaseURL), nil
+		}
+		if !cfg.Security.URLAllowlist.Enabled {
+			return redactedGrokBaseURLValidator(func(raw string) (string, error) {
+				return urlvalidator.ValidateURLFormat(raw, cfg.Security.URLAllowlist.AllowInsecureHTTP)
+			}), nil
+		}
+		return redactedGrokBaseURLValidator(func(raw string) (string, error) {
+			return urlvalidator.ValidateHTTPSURL(raw, urlvalidator.ValidationOptions{
+				AllowedHosts:     cfg.Security.URLAllowlist.UpstreamHosts,
+				RequireAllowlist: true,
+				AllowPrivate:     cfg.Security.URLAllowlist.AllowPrivateHosts,
+			})
+		}), nil
+	default:
+		return nil, fmt.Errorf("unsupported grok account type: %s", account.Type)
+	}
+}
+
+func redactedGrokBaseURLValidator(validator xai.BaseURLValidator) xai.BaseURLValidator {
+	return func(raw string) (string, error) {
+		validated, err := validator(raw)
+		if err != nil {
+			return "", errors.New("base URL rejected by URL security policy")
+		}
+		return validated, nil
+	}
+}
+
+func buildGrokResponsesURL(account *Account, cfg *config.Config) (string, error) {
+	validator, err := grokBaseURLValidator(account, cfg)
+	if err != nil {
+		return "", err
+	}
+	return xai.BuildResponsesURLWithValidator(account.GetGrokBaseURL(), validator)
+}
+
+func buildGrokChatCompletionsURL(account *Account, cfg *config.Config) (string, error) {
+	validator, err := grokBaseURLValidator(account, cfg)
+	if err != nil {
+		return "", err
+	}
+	return xai.BuildChatCompletionsURLWithValidator(account.GetGrokBaseURL(), validator)
+}
+
+func buildGrokMediaURL(account *Account, cfg *config.Config, endpoint GrokMediaEndpoint, requestID string) (string, error) {
+	validator, err := grokBaseURLValidator(account, cfg)
+	if err != nil {
+		return "", err
+	}
+	baseURL := account.GetGrokMediaBaseURL()
+	switch endpoint {
+	case GrokMediaEndpointImagesGenerations:
+		return xai.BuildImagesGenerationsURLWithValidator(baseURL, validator)
+	case GrokMediaEndpointImagesEdits:
+		return xai.BuildImagesEditsURLWithValidator(baseURL, validator)
+	case GrokMediaEndpointVideosGenerations:
+		return xai.BuildVideosGenerationsURLWithValidator(baseURL, validator)
+	case GrokMediaEndpointVideosEdits:
+		return xai.BuildVideosEditsURLWithValidator(baseURL, validator)
+	case GrokMediaEndpointVideosExtensions:
+		return xai.BuildVideosExtensionsURLWithValidator(baseURL, validator)
+	case GrokMediaEndpointVideoStatus:
+		return xai.BuildVideoURLWithValidator(baseURL, requestID, validator)
+	default:
+		return "", fmt.Errorf("unsupported grok media endpoint: %s", endpoint)
+	}
+}
diff --git a/backend/internal/service/grok_upstream_url_test.go b/backend/internal/service/grok_upstream_url_test.go
new file mode 100644
index 0000000000..7919e47202
--- /dev/null
+++ b/backend/internal/service/grok_upstream_url_test.go
@@ -0,0 +1,122 @@
+//go:build unit
+
+package service
+
+import (
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGrokAPIKeyURLPolicyFollowsGlobalSecurityConfig(t *testing.T) {
+	account := &Account{
+		Platform: PlatformGrok,
+		Type:     AccountTypeAPIKey,
+		Credentials: map[string]any{
+			"base_url": "http://grok.example.test/v1",
+		},
+	}
+
+	t.Run("insecure HTTP enabled with allowlist disabled", func(t *testing.T) {
+		cfg := &config.Config{}
+		cfg.Security.URLAllowlist.Enabled = false
+		cfg.Security.URLAllowlist.AllowInsecureHTTP = true
+
+		responsesURL, err := buildGrokResponsesURL(account, cfg)
+		require.NoError(t, err)
+		require.Equal(t, "http://grok.example.test/v1/responses", responsesURL)
+
+		chatURL, err := buildGrokChatCompletionsURL(account, cfg)
+		require.NoError(t, err)
+		require.Equal(t, "http://grok.example.test/v1/chat/completions", chatURL)
+
+		mediaURL, err := buildGrokMediaURL(account, cfg, GrokMediaEndpointImagesGenerations, "")
+		require.NoError(t, err)
+		require.Equal(t, "http://grok.example.test/v1/images/generations", mediaURL)
+	})
+
+	t.Run("insecure HTTP disabled", func(t *testing.T) {
+		cfg := &config.Config{}
+		cfg.Security.URLAllowlist.Enabled = false
+		cfg.Security.URLAllowlist.AllowInsecureHTTP = false
+
+		_, err := buildGrokResponsesURL(account, cfg)
+		require.EqualError(t, err, "invalid base url: base URL rejected by URL security policy")
+	})
+
+	t.Run("enabled allowlist remains HTTPS only", func(t *testing.T) {
+		cfg := &config.Config{}
+		cfg.Security.URLAllowlist.Enabled = true
+		cfg.Security.URLAllowlist.AllowInsecureHTTP = true
+		cfg.Security.URLAllowlist.UpstreamHosts = []string{"grok.example.test"}
+
+		_, err := buildGrokResponsesURL(account, cfg)
+		require.EqualError(t, err, "invalid base url: base URL rejected by URL security policy")
+	})
+}
+
+func TestGrokAPIKeyURLPolicyAppliesAllowlistAndPrivateHostControls(t *testing.T) {
+	account := &Account{
+		Platform: PlatformGrok,
+		Type:     AccountTypeAPIKey,
+		Credentials: map[string]any{
+			"base_url": "https://grok.example.test/v1",
+		},
+	}
+	cfg := &config.Config{}
+	cfg.Security.URLAllowlist.Enabled = true
+	cfg.Security.URLAllowlist.UpstreamHosts = []string{"grok.example.test"}
+
+	target, err := buildGrokResponsesURL(account, cfg)
+	require.NoError(t, err)
+	require.Equal(t, "https://grok.example.test/v1/responses", target)
+
+	cfg.Security.URLAllowlist.UpstreamHosts = []string{"other.example.test"}
+	_, err = buildGrokResponsesURL(account, cfg)
+	require.EqualError(t, err, "invalid base url: base URL rejected by URL security policy")
+
+	account.Credentials["base_url"] = "https://127.0.0.1/v1"
+	cfg.Security.URLAllowlist.UpstreamHosts = []string{"127.0.0.1"}
+	_, err = buildGrokResponsesURL(account, cfg)
+	require.EqualError(t, err, "invalid base url: base URL rejected by URL security policy")
+
+	cfg.Security.URLAllowlist.AllowPrivateHosts = true
+	target, err = buildGrokResponsesURL(account, cfg)
+	require.NoError(t, err)
+	require.Equal(t, "https://127.0.0.1/v1/responses", target)
+}
+
+func TestGrokAPIKeyURLPolicyRedactsMalformedConfiguredURL(t *testing.T) {
+	account := &Account{
+		Platform: PlatformGrok,
+		Type:     AccountTypeAPIKey,
+		Credentials: map[string]any{
+			"base_url": "https://%zz:secret@grok.example.test/v1",
+		},
+	}
+	cfg := &config.Config{}
+	cfg.Security.URLAllowlist.AllowInsecureHTTP = true
+
+	_, err := buildGrokResponsesURL(account, cfg)
+	require.EqualError(t, err, "invalid base url: base URL rejected by URL security policy")
+	require.NotContains(t, err.Error(), "secret")
+}
+
+func TestGrokOAuthURLPolicyIgnoresAPIKeyOverrides(t *testing.T) {
+	account := &Account{
+		Platform: PlatformGrok,
+		Type:     AccountTypeOAuth,
+		Credentials: map[string]any{
+			"base_url": "http://attacker.example.test/v1",
+		},
+	}
+	cfg := &config.Config{}
+	cfg.Security.URLAllowlist.Enabled = false
+	cfg.Security.URLAllowlist.AllowInsecureHTTP = true
+
+	target, err := buildGrokResponsesURL(account, cfg)
+	require.NoError(t, err)
+	require.Equal(t, xai.DefaultCLIBaseURL+"/responses", target)
+}
diff --git a/backend/internal/service/openai_account_runtime_block_fastpath.go b/backend/internal/service/openai_account_runtime_block_fastpath.go
index 978b740a56..00d971ba22 100644
--- a/backend/internal/service/openai_account_runtime_block_fastpath.go
+++ b/backend/internal/service/openai_account_runtime_block_fastpath.go
@@ -16,6 +16,13 @@ const (
 	openAIOAuth429StormMaxAccountSwitches = 1
 )
 
+// OpenAIOAuth429FailoverState tracks the request-local follow-up budget after
+// the first Grok OAuth 429. Once that 429 occurs, exactly one different account
+// may be attempted; any failure from that follow-up account ends failover.
+type OpenAIOAuth429FailoverState struct {
+	grokOAuth429FollowupPending bool
+}
+
 func openAIAccountStateContext(ctx context.Context) (context.Context, context.CancelFunc) {
 	base := context.Background()
 	if ctx != nil {
@@ -210,14 +217,28 @@ func (s *OpenAIGatewayService) isOpenAIOAuth429Storm() bool {
 	return s.openaiOAuth429WindowCount.Load() >= openAIOAuth429StormThreshold
 }
 
-func (s *OpenAIGatewayService) ShouldStopOpenAIOAuth429Failover(account *Account, statusCode int, failedSwitches int) bool {
-	if statusCode != http.StatusTooManyRequests || failedSwitches < openAIOAuth429StormMaxAccountSwitches {
+func (s *OpenAIGatewayService) ShouldStopOpenAIOAuth429Failover(account *Account, statusCode int, failedSwitches int, state *OpenAIOAuth429FailoverState) bool {
+	if failedSwitches < openAIOAuth429StormMaxAccountSwitches {
 		return false
 	}
-	if isGrokOAuthAccount(account) {
+	if state != nil && state.grokOAuth429FollowupPending {
+		// The follow-up budget was armed by a Grok OAuth 429. Consume it on
+		// any failing follow-up account, even if a mixed pool selected an API-key
+		// account next.
 		return true
 	}
-	if !isOpenAIOAuthAccount(account) {
+	if isGrokOAuthAccount(account) {
+		if state == nil {
+			// Preserve the old threshold for callers that have not adopted the
+			// request-local state contract yet.
+			return statusCode == http.StatusTooManyRequests && failedSwitches >= 2
+		}
+		if statusCode == http.StatusTooManyRequests {
+			state.grokOAuth429FollowupPending = true
+		}
+		return false
+	}
+	if statusCode != http.StatusTooManyRequests || !isOpenAIOAuthAccount(account) {
 		return false
 	}
 	return s.isOpenAIOAuth429Storm()
diff --git a/backend/internal/service/openai_account_runtime_block_fastpath_test.go b/backend/internal/service/openai_account_runtime_block_fastpath_test.go
index a51c13c531..7d7cfbda50 100644
--- a/backend/internal/service/openai_account_runtime_block_fastpath_test.go
+++ b/backend/internal/service/openai_account_runtime_block_fastpath_test.go
@@ -135,26 +135,45 @@ func TestShouldStopOpenAIOAuth429Failover_OnlyDuringStorm(t *testing.T) {
 	svc := &OpenAIGatewayService{}
 	account := &Account{ID: 42, Platform: PlatformOpenAI, Type: AccountTypeOAuth}
 	apiKeyAccount := &Account{ID: 43, Platform: PlatformOpenAI, Type: AccountTypeAPIKey}
+	var state OpenAIOAuth429FailoverState
 
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1))
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1, &state))
 
 	for i := 0; i < openAIOAuth429StormThreshold; i++ {
 		svc.recordOpenAIOAuth429()
 	}
 
-	require.True(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(apiKeyAccount, http.StatusTooManyRequests, 1))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusInternalServerError, 1))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 0))
+	require.True(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1, &state))
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(apiKeyAccount, http.StatusTooManyRequests, 1, &state))
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusInternalServerError, 1, &state))
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 0, &state))
 }
 
-func TestShouldStopOpenAIOAuth429Failover_StopsGrokAfterFirst429Switch(t *testing.T) {
+func TestShouldStopOpenAIOAuth429Failover_TracksOneGrokFollowupAttempt(t *testing.T) {
 	svc := &OpenAIGatewayService{}
 	account := &Account{ID: 44, Platform: PlatformGrok, Type: AccountTypeOAuth}
 	apiKeyAccount := &Account{ID: 45, Platform: PlatformGrok, Type: AccountTypeAPIKey}
 
-	require.True(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 0))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(apiKeyAccount, http.StatusTooManyRequests, 1))
-	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusInternalServerError, 1))
+	t.Run("429 then 500 stops after one followup", func(t *testing.T) {
+		var state OpenAIOAuth429FailoverState
+		require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1, &state))
+		require.True(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusInternalServerError, 2, &state))
+	})
+
+	t.Run("500 then 429 still allows one followup", func(t *testing.T) {
+		var state OpenAIOAuth429FailoverState
+		require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusInternalServerError, 1, &state))
+		require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 2, &state))
+		require.True(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusBadGateway, 3, &state))
+	})
+
+	t.Run("OAuth 429 then API-key failure consumes the same followup", func(t *testing.T) {
+		var state OpenAIOAuth429FailoverState
+		require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 1, &state))
+		require.True(t, svc.ShouldStopOpenAIOAuth429Failover(apiKeyAccount, http.StatusInternalServerError, 2, &state))
+	})
+
+	var state OpenAIOAuth429FailoverState
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(account, http.StatusTooManyRequests, 0, &state))
+	require.False(t, svc.ShouldStopOpenAIOAuth429Failover(apiKeyAccount, http.StatusTooManyRequests, 2, &state))
 }
diff --git a/backend/internal/service/openai_gateway_chat_completions_raw.go b/backend/internal/service/openai_gateway_chat_completions_raw.go
index 095d544f89..800d53be32 100644
--- a/backend/internal/service/openai_gateway_chat_completions_raw.go
+++ b/backend/internal/service/openai_gateway_chat_completions_raw.go
@@ -9,7 +9,6 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
-	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/Wei-Shaw/sub2api/internal/util/responseheaders"
 	"github.com/gin-gonic/gin"
 	"github.com/tidwall/gjson"
@@ -202,7 +201,7 @@ func (s *OpenAIGatewayService) forwardAsRawChatCompletions(
 	}
 
 	if account.Platform == PlatformGrok {
-		s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+		s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 	}
 
 	// 8. Forward response
@@ -222,7 +221,7 @@ func (s *OpenAIGatewayService) forwardAsRawChatCompletions(
 
 func (s *OpenAIGatewayService) rawChatCompletionsURL(account *Account) (string, error) {
 	if account.Platform == PlatformGrok {
-		targetURL, err := xai.BuildChatCompletionsURL(account.GetGrokBaseURL())
+		targetURL, err := buildGrokChatCompletionsURL(account, s.cfg)
 		if err != nil {
 			return "", fmt.Errorf("invalid grok base_url: %w", err)
 		}
diff --git a/backend/internal/service/openai_gateway_grok.go b/backend/internal/service/openai_gateway_grok.go
index 675b4bc9f9..92cf2910c6 100644
--- a/backend/internal/service/openai_gateway_grok.go
+++ b/backend/internal/service/openai_gateway_grok.go
@@ -11,6 +11,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/apicompat"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/gin-gonic/gin"
@@ -25,6 +26,10 @@ const (
 	grokCLIVersion                         = "0.2.93"
 	grokDefaultResponsesModel              = "grok-4.5"
 	grokRateLimitFallbackCooldown          = 2 * time.Minute
+	grokRateLimitRepeatCooldown            = 10 * time.Minute
+	grokRateLimitSustainedCooldown         = 30 * time.Minute
+	grokRateLimitMaxAdaptiveCooldown       = time.Hour
+	grokRateLimitBackoffQuietPeriod        = time.Hour
 )
 
 func (s *OpenAIGatewayService) forwardGrokResponses(
@@ -61,7 +66,7 @@ func (s *OpenAIGatewayService) forwardGrokResponses(
 
 	upstreamCtx, releaseUpstreamCtx := detachUpstreamContext(ctx)
 	defer releaseUpstreamCtx()
-	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, patchedBody, token, cacheIdentity)
+	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, patchedBody, token, cacheIdentity, s.cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -107,7 +112,7 @@ func (s *OpenAIGatewayService) forwardGrokResponses(
 		return s.handleErrorResponse(ctx, resp, c, account, patchedBody, upstreamModel)
 	}
 
-	s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+	s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 
 	var usage *OpenAIUsage
 	var firstTokenMs *int
@@ -574,7 +579,7 @@ func (s *OpenAIGatewayService) describeGrokComposerImage(
 	upstreamCtx, releaseUpstreamCtx := detachUpstreamContext(ctx)
 	// Image-description probes are auxiliary requests, not conversation turns.
 	// Do not bind them to the caller's Grok prompt-cache identity.
-	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, body, token, "")
+	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, body, token, "", s.cfg)
 	releaseUpstreamCtx()
 	if err != nil {
 		return "", OpenAIUsage{}, fmt.Errorf("build grok composer image bridge request: %w", err)
@@ -618,7 +623,7 @@ func (s *OpenAIGatewayService) describeGrokComposerImage(
 		return "", OpenAIUsage{}, fmt.Errorf("grok composer image bridge upstream error: %s", upstreamMsg)
 	}
 
-	s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+	s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 	respBody, err := ReadUpstreamResponseBody(resp.Body, s.cfg, c, nil)
 	if err != nil {
 		return "", OpenAIUsage{}, fmt.Errorf("read grok composer image bridge response: %w", err)
@@ -740,8 +745,8 @@ func addOpenAIUsage(dst *OpenAIUsage, usage OpenAIUsage) {
 	dst.ImageOutputTokens += usage.ImageOutputTokens
 }
 
-func buildGrokResponsesRequest(ctx context.Context, c *gin.Context, account *Account, body []byte, token, cacheIdentity string) (*http.Request, error) {
-	targetURL, err := xai.BuildResponsesURL(account.GetGrokBaseURL())
+func buildGrokResponsesRequest(ctx context.Context, c *gin.Context, account *Account, body []byte, token, cacheIdentity string, cfg *config.Config) (*http.Request, error) {
+	targetURL, err := buildGrokResponsesURL(account, cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -780,11 +785,12 @@ func (s *OpenAIGatewayService) updateGrokUsageSnapshot(ctx context.Context, acco
 	}
 	accountID := account.ID
 	now := time.Now()
-	resetAt, hasActiveLimit := grokRateLimitResetAt(snapshot, now)
+	resetAt, hasActiveLimit := grokRateLimitResetAtForAccount(account, snapshot, now)
 	if hasActiveLimit {
 		normalizeGrokExhaustedWindowResets(snapshot, resetAt, now)
 	}
-	critical := snapshot.StatusCode == http.StatusTooManyRequests || hasActiveLimit
+	recovery := isSuccessfulGrokRateLimitRecovery(account, snapshot)
+	critical := snapshot.StatusCode == http.StatusTooManyRequests || hasActiveLimit || recovery
 	if s.codexSnapshotThrottle != nil {
 		allowed := s.codexSnapshotThrottle.Allow(accountID, now)
 		if !critical && !allowed {
@@ -810,6 +816,23 @@ func (s *OpenAIGatewayService) updateGrokUsageSnapshot(ctx context.Context, acco
 	// on the passive snapshot scheduler check.
 	if hasActiveLimit {
 		s.rateLimitGrok(stateCtx, account, resetAt)
+	} else if recovery {
+		clearGrokRateLimitAfterRecovery(stateCtx, s.accountRepo, account)
+	}
+}
+
+func (s *OpenAIGatewayService) updateGrokUsageFromResponse(ctx context.Context, account *Account, headers http.Header, statusCode int) {
+	snapshot := parseGrokQuotaSnapshot(headers, statusCode, time.Now())
+	if snapshot != nil {
+		s.updateGrokUsageSnapshot(ctx, account, snapshot)
+		return
+	}
+	// Successful responses are recovery evidence even when the upstream omits
+	// optional quota headers. Do not replace an informative stored snapshot with
+	// an empty one; only clear the exact observed cooldown generation.
+	recoverySnapshot := &xai.QuotaSnapshot{StatusCode: statusCode}
+	if isSuccessfulGrokRateLimitRecovery(account, recoverySnapshot) {
+		clearGrokRateLimitAfterRecovery(ctx, s.accountRepo, account)
 	}
 }
 
@@ -900,6 +923,37 @@ func grokRateLimitResetAt(snapshot *xai.QuotaSnapshot, now time.Time) (time.Time
 	return time.Time{}, false
 }
 
+func grokRateLimitResetAtForAccount(account *Account, snapshot *xai.QuotaSnapshot, now time.Time) (time.Time, bool) {
+	resetAt, limited := grokRateLimitResetAt(snapshot, now)
+	if !limited || !isGrokOAuthAccount(account) || snapshot == nil || snapshot.StatusCode != http.StatusTooManyRequests {
+		return resetAt, limited
+	}
+	if account.RateLimitedAt == nil || account.RateLimitResetAt == nil {
+		return resetAt, true
+	}
+	previousResetAt := *account.RateLimitResetAt
+	if previousResetAt.After(now) || now.Sub(previousResetAt) > grokRateLimitBackoffQuietPeriod {
+		return resetAt, true
+	}
+	previousCooldown := previousResetAt.Sub(*account.RateLimitedAt)
+	if previousCooldown <= 0 {
+		return resetAt, true
+	}
+
+	adaptiveCooldown := grokRateLimitRepeatCooldown
+	switch {
+	case previousCooldown >= grokRateLimitSustainedCooldown:
+		adaptiveCooldown = grokRateLimitMaxAdaptiveCooldown
+	case previousCooldown >= grokRateLimitRepeatCooldown:
+		adaptiveCooldown = grokRateLimitSustainedCooldown
+	}
+	adaptiveResetAt := now.Add(adaptiveCooldown)
+	if adaptiveResetAt.After(resetAt) {
+		resetAt = adaptiveResetAt
+	}
+	return resetAt, true
+}
+
 func normalizeGrokRateLimitResetAt(account *Account, resetAt, now time.Time) time.Time {
 	if !resetAt.After(now) {
 		resetAt = now.Add(grokRateLimitFallbackCooldown)
@@ -914,6 +968,33 @@ type grokRateLimitExtendingRepository interface {
 	SetRateLimitedIfLater(ctx context.Context, id int64, resetAt time.Time) error
 }
 
+type grokRateLimitRecoveryRepository interface {
+	ClearRateLimitIfObserved(ctx context.Context, id int64, observedLimitedAt, observedResetAt time.Time) (bool, error)
+}
+
+func isSuccessfulGrokRateLimitRecovery(account *Account, snapshot *xai.QuotaSnapshot) bool {
+	return isGrokOAuthAccount(account) &&
+		account.RateLimitedAt != nil &&
+		account.RateLimitResetAt != nil &&
+		snapshot != nil &&
+		snapshot.StatusCode >= http.StatusOK &&
+		snapshot.StatusCode < http.StatusMultipleChoices
+}
+
+func clearGrokRateLimitAfterRecovery(ctx context.Context, repo AccountRepository, account *Account) {
+	if repo == nil || account == nil || account.RateLimitedAt == nil || account.RateLimitResetAt == nil || ctx.Err() != nil {
+		return
+	}
+	recoveryRepo, ok := repo.(grokRateLimitRecoveryRepository)
+	if !ok {
+		return
+	}
+	_, err := recoveryRepo.ClearRateLimitIfObserved(ctx, account.ID, *account.RateLimitedAt, *account.RateLimitResetAt)
+	if err != nil {
+		slog.Warn("grok_rate_limit_recovery_clear_failed", "account_id", account.ID, "error", err)
+	}
+}
+
 func persistGrokRateLimit(ctx context.Context, repo AccountRepository, account *Account, resetAt time.Time) {
 	if repo == nil || account == nil || account.ID <= 0 {
 		return
diff --git a/backend/internal/service/openai_gateway_grok_chat_bridge.go b/backend/internal/service/openai_gateway_grok_chat_bridge.go
index fe9cfb09fd..6fd58b2db1 100644
--- a/backend/internal/service/openai_gateway_grok_chat_bridge.go
+++ b/backend/internal/service/openai_gateway_grok_chat_bridge.go
@@ -10,7 +10,6 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/pkg/apicompat"
-	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/gin-gonic/gin"
 )
 
@@ -258,7 +257,7 @@ func (s *OpenAIGatewayService) forwardGrokChatCompletionsViaResponses(
 		return nil, fmt.Errorf("get grok access token: %w", err)
 	}
 	upstreamCtx, releaseUpstreamCtx := detachUpstreamContext(ctx)
-	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, responsesBody, token, cacheIdentity)
+	upstreamReq, err := buildGrokResponsesRequest(upstreamCtx, c, account, responsesBody, token, cacheIdentity, s.cfg)
 	releaseUpstreamCtx()
 	if err != nil {
 		return nil, fmt.Errorf("build grok responses bridge request: %w", err)
@@ -301,7 +300,7 @@ func (s *OpenAIGatewayService) forwardGrokChatCompletionsViaResponses(
 		return s.handleChatCompletionsErrorResponse(resp, c, account, billingModel)
 	}
 
-	s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+	s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 
 	var result *OpenAIForwardResult
 	if clientStream {
diff --git a/backend/internal/service/openai_gateway_grok_test.go b/backend/internal/service/openai_gateway_grok_test.go
index 4f7ed05edf..d93415b2e0 100644
--- a/backend/internal/service/openai_gateway_grok_test.go
+++ b/backend/internal/service/openai_gateway_grok_test.go
@@ -256,7 +256,7 @@ func TestBuildGrokResponsesRequestUsesAccountBaseURLAndBearerToken(t *testing.T)
 		},
 	}
 
-	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "access-token", "isolated-cache-id")
+	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "access-token", "isolated-cache-id", nil)
 	require.NoError(t, err)
 	require.Equal(t, http.MethodPost, req.Method)
 	require.Equal(t, xai.DefaultCLIBaseURL+"/responses", req.URL.String())
@@ -280,7 +280,7 @@ func TestBuildGrokResponsesRequestAllowsPublicAPIKeyBaseURLByDefault(t *testing.
 		},
 	}
 
-	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "api-key", "")
+	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "api-key", "", nil)
 	require.NoError(t, err)
 	require.Equal(t, "https://grok.example.test/v1/responses", req.URL.String())
 	require.Equal(t, "Bearer api-key", req.Header.Get("Authorization"))
@@ -299,7 +299,7 @@ func TestBuildGrokResponsesRequestPinsOAuthCustomBaseURLByDefault(t *testing.T)
 		},
 	}
 
-	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "access-token", "")
+	req, err := buildGrokResponsesRequest(context.Background(), nil, account, []byte(`{"model":"grok-4.3"}`), "access-token", "", nil)
 	require.NoError(t, err)
 	require.Equal(t, xai.DefaultCLIBaseURL+"/responses", req.URL.String())
 }
@@ -1077,6 +1077,41 @@ func TestAccountTestServiceGrokAPIKeyUsesXAIResponses(t *testing.T) {
 	require.Contains(t, recorder.Body.String(), `"type":"test_complete"`)
 }
 
+func TestAccountTestServiceGrokAPIKeyAllowsConfiguredHTTPWhenGlobalPolicyDoes(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	account := &Account{
+		ID:          55,
+		Name:        "grok-api-key-http",
+		Platform:    PlatformGrok,
+		Type:        AccountTypeAPIKey,
+		Concurrency: 1,
+		Credentials: map[string]any{
+			"api_key":  "third-party-key",
+			"base_url": "http://grok.example.test/v1",
+		},
+	}
+	upstream := &httpUpstreamRecorder{resp: &http.Response{
+		StatusCode: http.StatusOK,
+		Header:     http.Header{"Content-Type": []string{"text/event-stream"}},
+		Body: io.NopCloser(strings.NewReader(
+			"data: {\"type\":\"response.output_text.delta\",\"delta\":\"ok\"}\n\n" +
+				"data: {\"type\":\"response.completed\"}\n\n",
+		)),
+	}}
+	svc := &AccountTestService{cfg: rawChatCompletionsTestConfig(), httpUpstream: upstream}
+	recorder := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(recorder)
+	c.Request = httptest.NewRequest(http.MethodPost, "/api/v1/admin/accounts/55/test", nil)
+
+	err := svc.testGrokAccountConnection(c, account, "grok")
+	require.NoError(t, err)
+	require.Equal(t, "http://grok.example.test/v1/responses", upstream.lastReq.URL.String())
+	require.Equal(t, "Bearer third-party-key", upstream.lastReq.Header.Get("Authorization"))
+	require.Empty(t, upstream.lastReq.Header.Get("X-Grok-Client-Version"))
+	require.Contains(t, recorder.Body.String(), `"type":"test_complete"`)
+}
+
 func TestForwardAsChatCompletionsForGrokStreamingUsesRawXAIChatCompletions(t *testing.T) {
 	gin.SetMode(gin.TestMode)
 
@@ -1144,10 +1179,15 @@ func TestForwardGrokResponsesNonStreamingUsesCacheIdentityAndCachedUsage(t *test
 	c.Set("api_key", &APIKey{ID: 5202})
 
 	account := healthyGrokOAuthGatewayTestAccount(56, "access-token")
+	observedResetAt := time.Now().Add(-time.Second).UTC().Truncate(time.Second)
+	observedLimitedAt := observedResetAt.Add(-grokRateLimitRepeatCooldown)
+	account.RateLimitedAt = &observedLimitedAt
+	account.RateLimitResetAt = &observedResetAt
 	repo := &grokQuotaAccountRepo{
 		mockAccountRepoForPlatform: &mockAccountRepoForPlatform{
 			accountsByID: map[int64]*Account{56: account},
 		},
+		recoveryClearResult: true,
 	}
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
@@ -1180,6 +1220,9 @@ func TestForwardGrokResponsesNonStreamingUsesCacheIdentityAndCachedUsage(t *test
 	require.False(t, gjson.GetBytes(upstream.lastBody, "tools").Exists())
 	require.False(t, gjson.GetBytes(upstream.lastBody, "tool_choice").Exists())
 	require.Equal(t, "resp_grok_non_stream", gjson.Get(recorder.Body.String(), "id").String())
+	require.Equal(t, 1, repo.recoveryClearCalls)
+	require.Equal(t, observedLimitedAt, repo.recoveryObservedAt)
+	require.Equal(t, observedResetAt, repo.recoveryObservedReset)
 }
 
 func TestForwardGrokResponsesFailoverKeepsCacheIdentityAcrossAccounts(t *testing.T) {
@@ -1565,6 +1608,102 @@ func TestHandleGrokAccountUpstreamError429UsesFallbackReset(t *testing.T) {
 	require.Zero(t, repo.tempUnschedCalls)
 }
 
+func TestGrokRateLimitResetAtForAccountEscalatesRepeated429s(t *testing.T) {
+	now := time.Now().UTC().Truncate(time.Second)
+	retryAfter := 45
+	snapshot := &xai.QuotaSnapshot{
+		StatusCode:        http.StatusTooManyRequests,
+		RetryAfterSeconds: &retryAfter,
+		UpdatedAt:         now.Format(time.RFC3339),
+	}
+	tests := []struct {
+		name             string
+		previousCooldown time.Duration
+		wantCooldown     time.Duration
+	}{
+		{name: "repeat after short boundary", previousCooldown: 45 * time.Second, wantCooldown: grokRateLimitRepeatCooldown},
+		{name: "sustained repeat", previousCooldown: grokRateLimitRepeatCooldown, wantCooldown: grokRateLimitSustainedCooldown},
+		{name: "capped repeat", previousCooldown: grokRateLimitSustainedCooldown, wantCooldown: grokRateLimitMaxAdaptiveCooldown},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			previousReset := now.Add(-time.Second)
+			previousLimited := previousReset.Add(-tt.previousCooldown)
+			account := &Account{
+				ID:               630,
+				Platform:         PlatformGrok,
+				Type:             AccountTypeOAuth,
+				RateLimitedAt:    &previousLimited,
+				RateLimitResetAt: &previousReset,
+			}
+
+			resetAt, limited := grokRateLimitResetAtForAccount(account, snapshot, now)
+
+			require.True(t, limited)
+			require.WithinDuration(t, now.Add(tt.wantCooldown), resetAt, time.Second)
+		})
+	}
+}
+
+func TestGrokRateLimitResetAtForAccountPreservesAuthoritativeAndQuietRecovery(t *testing.T) {
+	now := time.Now().UTC().Truncate(time.Second)
+	retryAfter := 45
+	previousReset := now.Add(-grokRateLimitBackoffQuietPeriod - time.Second)
+	previousLimited := previousReset.Add(-grokRateLimitSustainedCooldown)
+	account := &Account{
+		ID:               631,
+		Platform:         PlatformGrok,
+		Type:             AccountTypeOAuth,
+		RateLimitedAt:    &previousLimited,
+		RateLimitResetAt: &previousReset,
+	}
+	snapshot := &xai.QuotaSnapshot{
+		StatusCode:        http.StatusTooManyRequests,
+		RetryAfterSeconds: &retryAfter,
+		UpdatedAt:         now.Format(time.RFC3339),
+	}
+
+	resetAt, limited := grokRateLimitResetAtForAccount(account, snapshot, now)
+	require.True(t, limited)
+	require.WithinDuration(t, now.Add(45*time.Second), resetAt, time.Second)
+
+	authoritativeReset := now.Add(2 * time.Hour)
+	remaining := int64(0)
+	snapshot.Requests = &xai.QuotaWindow{Remaining: &remaining, ResetUnix: grokInt64PtrForTest(authoritativeReset.Unix())}
+	recentReset := now.Add(-time.Second)
+	recentLimited := recentReset.Add(-grokRateLimitSustainedCooldown)
+	account.RateLimitResetAt = &recentReset
+	account.RateLimitedAt = &recentLimited
+
+	resetAt, limited = grokRateLimitResetAtForAccount(account, snapshot, now)
+	require.True(t, limited)
+	require.WithinDuration(t, authoritativeReset, resetAt, time.Second)
+}
+
+func TestGrokRateLimitResetAtForAccountLeavesAPIKey429PolicyUnchanged(t *testing.T) {
+	now := time.Now().UTC().Truncate(time.Second)
+	retryAfter := 45
+	previousReset := now.Add(-time.Second)
+	previousLimited := previousReset.Add(-grokRateLimitSustainedCooldown)
+	account := &Account{
+		ID:               632,
+		Platform:         PlatformGrok,
+		Type:             AccountTypeAPIKey,
+		RateLimitedAt:    &previousLimited,
+		RateLimitResetAt: &previousReset,
+	}
+	snapshot := &xai.QuotaSnapshot{
+		StatusCode:        http.StatusTooManyRequests,
+		RetryAfterSeconds: &retryAfter,
+		UpdatedAt:         now.Format(time.RFC3339),
+	}
+
+	resetAt, limited := grokRateLimitResetAtForAccount(account, snapshot, now)
+	require.True(t, limited)
+	require.WithinDuration(t, now.Add(45*time.Second), resetAt, time.Second)
+}
+
 func TestGrokRateLimitResetAtUsesFutureWindowAfterRetryAfterExpires(t *testing.T) {
 	now := time.Now().UTC().Truncate(time.Second)
 	observedAt := now.Add(-2 * time.Minute)
@@ -1666,6 +1805,72 @@ func TestUpdateGrokUsageSnapshotAvailableSuccessDoesNotSetRateLimited(t *testing
 	require.Zero(t, repo.rateLimitedCalls)
 }
 
+func TestUpdateGrokUsageFromResponseHeaderlessSuccessClearsObservedCooldown(t *testing.T) {
+	now := time.Now().UTC().Truncate(time.Second)
+	limitedAt := now.Add(-grokRateLimitRepeatCooldown)
+	observedResetAt := now.Add(-time.Second)
+	account := &Account{
+		ID:               660,
+		Platform:         PlatformGrok,
+		Type:             AccountTypeOAuth,
+		RateLimitedAt:    &limitedAt,
+		RateLimitResetAt: &observedResetAt,
+	}
+	repo := &grokQuotaAccountRepo{recoveryClearResult: true}
+	svc := &OpenAIGatewayService{
+		accountRepo:           repo,
+		codexSnapshotThrottle: newAccountWriteThrottle(time.Hour),
+	}
+
+	svc.updateGrokUsageFromResponse(context.Background(), account, nil, http.StatusOK)
+
+	require.Zero(t, repo.updateCalls, "headerless success must not overwrite an informative quota snapshot")
+	require.Equal(t, 1, repo.recoveryClearCalls)
+	require.Equal(t, limitedAt, repo.recoveryObservedAt)
+	require.Equal(t, observedResetAt, repo.recoveryObservedReset)
+	require.Same(t, &observedResetAt, account.RateLimitResetAt, "shared account snapshots must not be mutated in place")
+}
+
+func TestUpdateGrokUsageFromResponseRecoveryRespectsCancellationAndAPIKeyBoundary(t *testing.T) {
+	now := time.Now().UTC().Truncate(time.Second)
+	observedResetAt := now.Add(-time.Second)
+	observedLimitedAt := observedResetAt.Add(-grokRateLimitRepeatCooldown)
+
+	t.Run("parent cancellation does not mutate account state", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		cancel()
+		account := &Account{
+			ID:               661,
+			Platform:         PlatformGrok,
+			Type:             AccountTypeOAuth,
+			RateLimitedAt:    &observedLimitedAt,
+			RateLimitResetAt: &observedResetAt,
+		}
+		repo := &grokQuotaAccountRepo{recoveryClearResult: true}
+		svc := &OpenAIGatewayService{accountRepo: repo}
+
+		svc.updateGrokUsageFromResponse(ctx, account, nil, http.StatusOK)
+
+		require.Zero(t, repo.recoveryClearCalls)
+	})
+
+	t.Run("API key success does not alter OAuth cooldown state", func(t *testing.T) {
+		account := &Account{
+			ID:               662,
+			Platform:         PlatformGrok,
+			Type:             AccountTypeAPIKey,
+			RateLimitedAt:    &observedLimitedAt,
+			RateLimitResetAt: &observedResetAt,
+		}
+		repo := &grokQuotaAccountRepo{recoveryClearResult: true}
+		svc := &OpenAIGatewayService{accountRepo: repo}
+
+		svc.updateGrokUsageFromResponse(context.Background(), account, nil, http.StatusOK)
+
+		require.Zero(t, repo.recoveryClearCalls)
+	})
+}
+
 func TestUpdateGrokUsageSnapshotExhaustedSuccessWithoutResetUsesFallback(t *testing.T) {
 	repo := &grokQuotaAccountRepo{}
 	svc := &OpenAIGatewayService{accountRepo: repo}
diff --git a/backend/internal/service/openai_gateway_messages.go b/backend/internal/service/openai_gateway_messages.go
index e2add90ff2..067d458b89 100644
--- a/backend/internal/service/openai_gateway_messages.go
+++ b/backend/internal/service/openai_gateway_messages.go
@@ -14,7 +14,6 @@ import (
 	"github.com/Wei-Shaw/sub2api/internal/pkg/claude"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/openai_compat"
-	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/Wei-Shaw/sub2api/internal/util/responseheaders"
 	"github.com/gin-gonic/gin"
 	"go.uber.org/zap"
@@ -273,7 +272,7 @@ func (s *OpenAIGatewayService) ForwardAsAnthropic(
 	upstreamCtx, releaseUpstreamCtx := detachUpstreamContext(ctx)
 	var upstreamReq *http.Request
 	if account.Platform == PlatformGrok {
-		upstreamReq, err = buildGrokResponsesRequest(upstreamCtx, c, account, responsesBody, token, grokCacheIdentity)
+		upstreamReq, err = buildGrokResponsesRequest(upstreamCtx, c, account, responsesBody, token, grokCacheIdentity, s.cfg)
 	} else {
 		upstreamReq, err = s.buildUpstreamRequest(upstreamCtx, c, account, responsesBody, token, isStream, promptCacheKey, false)
 	}
@@ -344,7 +343,7 @@ func (s *OpenAIGatewayService) ForwardAsAnthropic(
 		return s.handleAnthropicErrorResponse(resp, c, account, billingModel)
 	}
 	if account.Platform == PlatformGrok && account.Type == AccountTypeOAuth && !account.IsShadow() {
-		s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+		s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 	}
 
 	if account.Type == AccountTypeOAuth && promptCacheKey != "" {
diff --git a/backend/internal/service/openai_ws_http_bridge.go b/backend/internal/service/openai_ws_http_bridge.go
index dbc24c850a..77a5e59329 100644
--- a/backend/internal/service/openai_ws_http_bridge.go
+++ b/backend/internal/service/openai_ws_http_bridge.go
@@ -12,7 +12,6 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
-	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/gin-gonic/gin"
 	"github.com/tidwall/gjson"
 )
@@ -193,7 +192,7 @@ func (s *OpenAIGatewayService) proxyOpenAIWSHTTPBridgeTurn(
 			releaseUpstreamCtx()
 			return nil, fmt.Errorf("apply grok prompt cache identity: %w", err)
 		}
-		upstreamReq, err = buildGrokResponsesRequest(upstreamCtx, c, account, body, token, grokCacheIdentity)
+		upstreamReq, err = buildGrokResponsesRequest(upstreamCtx, c, account, body, token, grokCacheIdentity, s.cfg)
 	} else {
 		upstreamReq, err = s.buildUpstreamRequestOpenAIPassthrough(upstreamCtx, c, account, body, token)
 	}
@@ -236,7 +235,7 @@ func (s *OpenAIGatewayService) proxyOpenAIWSHTTPBridgeTurn(
 		return nil, fmt.Errorf("upstream http bridge error: status=%d message=%s", resp.StatusCode, upstreamMsg)
 	}
 	if account.Platform == PlatformGrok {
-		s.updateGrokUsageSnapshot(ctx, account, xai.ParseQuotaHeaders(resp.Header, resp.StatusCode))
+		s.updateGrokUsageFromResponse(ctx, account, resp.Header, resp.StatusCode)
 	}
 
 	responseID := ""