diff --git a/backend/internal/service/account_test_models_test.go b/backend/internal/service/account_test_models_test.go
index ba8b511a57..59af5edbd9 100644
--- a/backend/internal/service/account_test_models_test.go
+++ b/backend/internal/service/account_test_models_test.go
@@ -9,7 +9,12 @@ import (
 )
 
 func TestFetchOpenAIAccountModelsOAuthPopulatesPickerFields(t *testing.T) {
-	_, calls := newCodexModelsOAuthCacheServer(t, `{"models":[{"slug":"new-oauth-model"},{"slug":"gpt-6-astra"}]}`)
+	_, calls := newCodexModelsOAuthCacheServer(t, `{"models":[
+		{"slug":"new-oauth-model","display_name":"New OAuth Model"},
+		{"slug":"gpt-5.6-sol"},
+		{"slug":"blank-display-name","display_name":"   "},
+		{"slug":"gpt-6-astra"}
+	]}`)
 	gateway := &OpenAIGatewayService{}
 	svc := &AccountTestService{openaiGatewayService: gateway}
 	account := newCodexModelsTestAccount()
@@ -20,9 +25,16 @@ func TestFetchOpenAIAccountModelsOAuthPopulatesPickerFields(t *testing.T) {
 	models, err := svc.FetchOpenAIAccountModels(ctx, account)
 	require.NoError(t, err)
 	require.Greater(t, len(models), 2)
-	for i, id := range []string{"new-oauth-model", "gpt-6-astra"} {
-		require.Equal(t, id, models[i].ID)
-		require.Equal(t, id, models[i].DisplayName)
+	// Upstream display name wins; a missing one falls back to the local catalog name,
+	// then to the raw slug.
+	for i, expected := range []struct{ id, displayName string }{
+		{id: "new-oauth-model", displayName: "New OAuth Model"},
+		{id: "gpt-5.6-sol", displayName: "GPT-5.6 Sol"},
+		{id: "blank-display-name", displayName: "blank-display-name"},
+		{id: "gpt-6-astra", displayName: "GPT-6 Astra"},
+	} {
+		require.Equal(t, expected.id, models[i].ID)
+		require.Equal(t, expected.displayName, models[i].DisplayName)
 		require.Equal(t, "model", models[i].Type)
 	}
 	ids := make([]string, 0, len(models))
@@ -35,7 +47,7 @@ func TestFetchOpenAIAccountModelsOAuthPopulatesPickerFields(t *testing.T) {
 	after, err := gateway.FetchOpenAIModelsList(ctx, account)
 	require.NoError(t, err)
 	require.Equal(t, before.Body, after.Body, "picker fields must not change the shared catalog")
-	require.NotContains(t, string(after.Body), "display_name")
+	require.Contains(t, string(after.Body), `"display_name":"New OAuth Model"`, "the shared catalog keeps the upstream display name")
 	require.EqualValues(t, 1, calls.Load(), "picker must reuse the shared discovery cache")
 }
 
@@ -70,6 +82,21 @@ func TestFetchOpenAIAccountModelsPreservesEmptyCatalog(t *testing.T) {
 	require.Empty(t, models, "an empty upstream catalog must not become a static model list")
 }
 
+func TestFetchOpenAIAccountModelsOAuthLabelsLocalImageModelsLikeUpstream(t *testing.T) {
+	newCodexModelsOAuthCacheServer(t, `{"models":[{"slug":"gpt-5.6-sol"}]}`)
+	svc := &AccountTestService{openaiGatewayService: &OpenAIGatewayService{}}
+	account := newCodexModelsTestAccount()
+	account.Credentials["model_mapping"] = map[string]any{"gpt-image-2.5-flare": "gpt-image-2.5-flare"}
+	models, err := svc.FetchOpenAIAccountModels(context.Background(), account)
+	require.NoError(t, err)
+	byID := make(map[string]string, len(models))
+	for _, model := range models {
+		byID[model.ID] = model.DisplayName
+	}
+	require.Equal(t, "GPT-5.6 Sol", byID["gpt-5.6-sol"], "upstream slug must not be the only label source")
+	require.Equal(t, "GPT Image 2.5 Flare", byID["gpt-image-2.5-flare"], "locally added models use the same naming rule")
+}
+
 func TestFetchOpenAIAccountModelsOAuthRespectsImageAllowlist(t *testing.T) {
 	newCodexModelsOAuthCacheServer(t, `{"models":[{"slug":"gpt-6-astra"}]}`)
 	svc := &AccountTestService{openaiGatewayService: &OpenAIGatewayService{}}
diff --git a/backend/internal/service/account_test_service.go b/backend/internal/service/account_test_service.go
index 44e29dfc1e..b57491e71b 100644
--- a/backend/internal/service/account_test_service.go
+++ b/backend/internal/service/account_test_service.go
@@ -178,6 +178,8 @@ func (s *AccountTestService) SetOpenAIGatewayService(gateway *OpenAIGatewayServi
 }
 
 // FetchOpenAIAccountModels uses the shared cached discovery path for the test picker.
+// It only fills picker-only gaps (local display-name fallbacks, OAuth image choices)
+// on its own copy; the shared catalog and its cache stay untouched.
 func (s *AccountTestService) FetchOpenAIAccountModels(ctx context.Context, account *Account) ([]openai.Model, error) {
 	if s == nil || s.openaiGatewayService == nil {
 		return nil, errors.New("OpenAI model discovery service is unavailable")
@@ -192,12 +194,14 @@ func (s *AccountTestService) FetchOpenAIAccountModels(ctx context.Context, accou
 	if err := json.Unmarshal(response.Body, &payload); err != nil {
 		return nil, fmt.Errorf("decode OpenAI account models: %w", err)
 	}
-	// Standard model catalogs do not require the fields used by the admin picker.
-	// Populate them here without changing the shared discovery response or cache.
+	// Every entry in the picker is labelled by the same rule: the upstream display
+	// name when the catalog has one, otherwise the local catalog name for that model
+	// ID, otherwise the raw ID. Without this the picker mixes "GPT-5.6 Sol" with
+	// "gpt-5.6-sol" for the same catalog.
 	for i := range payload.Data {
 		model := &payload.Data[i]
 		if strings.TrimSpace(model.DisplayName) == "" {
-			model.DisplayName = model.ID
+			model.DisplayName = openaiCodexDisplayName(model.ID)
 		}
 		if strings.TrimSpace(model.Type) == "" {
 			model.Type = "model"
@@ -219,7 +223,7 @@ func (s *AccountTestService) FetchOpenAIAccountModels(ctx context.Context, accou
 		}
 		for model := range account.GetModelMapping() {
 			if IsGPTImageGenerationModel(model) && !strings.Contains(model, "*") && !seen[model] {
-				payload.Data = append(payload.Data, openai.Model{ID: model, Object: "model", Type: "model", OwnedBy: "openai", DisplayName: model})
+				payload.Data = append(payload.Data, openai.Model{ID: model, Object: "model", Type: "model", OwnedBy: "openai", DisplayName: openaiCodexDisplayName(model)})
 			}
 		}
 	}
diff --git a/backend/internal/service/openai_models_list.go b/backend/internal/service/openai_models_list.go
index 42740c2df3..2a07f10d67 100644
--- a/backend/internal/service/openai_models_list.go
+++ b/backend/internal/service/openai_models_list.go
@@ -96,6 +96,10 @@ func modelCatalogEntries(body []byte, field string) (map[string]json.RawMessage,
 	return envelope, entries, nil
 }
 
+// standardOpenAIModelsBody projects either representation onto the OpenAI /v1/models
+// shape. Manifest entries are rebuilt to a minimal entry set; plain OpenAI lists keep
+// their upstream fields. Both keep display_name, which the admin picker and alias
+// projection read.
 func standardOpenAIModelsBody(body []byte, fromManifest bool) ([]byte, error) {
 	field, idField := "data", "id"
 	if fromManifest {
@@ -122,7 +126,19 @@ func standardOpenAIModelsBody(body []byte, fromManifest bool) ([]byte, error) {
 		}
 		seen[id] = struct{}{}
 		if fromManifest {
+			// Codex manifest entries carry dozens of client-only fields (instructions,
+			// model_messages, reasoning levels) that must not reach the public catalog,
+			// so the entry is rebuilt from scratch. The display name is the one manifest
+			// field user-facing surfaces need (admin test picker, mapping aliases), so it
+			// is carried over explicitly instead of being dropped with the rest.
+			var displayName string
+			if err := json.Unmarshal(entry["display_name"], &displayName); err == nil {
+				displayName = strings.TrimSpace(displayName)
+			}
 			entry = make(map[string]json.RawMessage)
+			if displayName != "" {
+				entry["display_name"], _ = json.Marshal(displayName)
+			}
 		}
 		entry["id"], _ = json.Marshal(id)
 		entry["object"] = json.RawMessage(`"model"`)
diff --git a/backend/internal/service/openai_models_list_test.go b/backend/internal/service/openai_models_list_test.go
index c898c06189..08df6e249c 100644
--- a/backend/internal/service/openai_models_list_test.go
+++ b/backend/internal/service/openai_models_list_test.go
@@ -58,12 +58,12 @@ func TestFetchOpenAIModelsListUsesStandardRequestAndIsolatesCodexCache(t *testin
 }
 
 func TestFetchOpenAIModelsListOAuthSharesManifestCache(t *testing.T) {
-	_, calls := newCodexModelsOAuthCacheServer(t, `{"models":[{"slug":"special-oauth-model"},{"slug":"gpt-image-1"}]}`)
+	_, calls := newCodexModelsOAuthCacheServer(t, `{"models":[{"slug":"special-oauth-model","display_name":"Special OAuth Model","description":"manifest only"},{"slug":"gpt-image-1"}]}`)
 	s := &OpenAIGatewayService{}
 	account := newCodexModelsTestAccount()
 	response, err := s.FetchOpenAIModelsList(context.Background(), account)
 	require.NoError(t, err)
-	require.JSONEq(t, `{"object":"list","data":[{"id":"special-oauth-model","object":"model","owned_by":"openai","created":0},{"id":"gpt-image-1","object":"model","owned_by":"openai","created":0}]}`, string(response.Body))
+	require.JSONEq(t, `{"object":"list","data":[{"id":"special-oauth-model","object":"model","owned_by":"openai","created":0,"display_name":"Special OAuth Model"},{"id":"gpt-image-1","object":"model","owned_by":"openai","created":0}]}`, string(response.Body))
 	manifest, err := s.FetchCodexModelsManifest(context.Background(), account, CodexCanonicalClientVersion(), "")
 	require.NoError(t, err)
 	require.Contains(t, string(manifest.Body), `"slug":"special-oauth-model"`)