Merge PR #1513

pkg/config/config.go

@@ -832,6 +832,16 @@ func LoadConfig(path string) (*Config, error) {
 	if len(tmp.ModelList) > 0 {
 		cfg.ModelList = nil
 	}
+	if len(tmp.ModelList) == 0 && tmp.HasProvidersConfig() {
+		// Legacy provider-only configs should not inherit the template
+		// model_list or template default model selection. Clear both so the
+		// old provider block can be migrated into an explicit model_list below.
+		cfg.ModelList = nil
+		if tmp.Agents.Defaults.ModelName == "" && tmp.Agents.Defaults.Model == "" {
+			cfg.Agents.Defaults.ModelName = ""
+			cfg.Agents.Defaults.Model = ""
+		}
+	}
 
 	if err := json.Unmarshal(data, cfg); err != nil {
 		return nil, err
@@ -847,6 +857,10 @@ func LoadConfig(path string) (*Config, error) {
 	// Auto-migrate: if only legacy providers config exists, convert to model_list
 	if len(cfg.ModelList) == 0 && cfg.HasProvidersConfig() {
 		cfg.ModelList = ConvertProvidersToModelList(cfg)
+		if cfg.Agents.Defaults.GetModelName() == "" && len(cfg.ModelList) > 0 {
+			cfg.Agents.Defaults.ModelName = cfg.ModelList[0].ModelName
+			cfg.Agents.Defaults.Model = ""
+		}
 	}
 
 	// Validate model_list for uniqueness and required fields

pkg/config/config_test.go

@@ -460,6 +460,84 @@ func TestLoadConfig_WebToolsProxy(t *testing.T) {
 	}
 }
 
+func TestLoadConfig_LegacyProvidersConfigMigratesWithoutTemplateModelLeak(t *testing.T) {
+	tmpDir := t.TempDir()
+	configPath := filepath.Join(tmpDir, "config.json")
+	configJSON := `{
+  "providers": {
+    "gemini": {
+      "api_key": "gemini-test-key"
+    }
+  }
+}`
+	if err := os.WriteFile(configPath, []byte(configJSON), 0o600); err != nil {
+		t.Fatalf("os.WriteFile() error: %v", err)
+	}
+
+	cfg, err := LoadConfig(configPath)
+	if err != nil {
+		t.Fatalf("LoadConfig() error: %v", err)
+	}
+
+	if got := cfg.Agents.Defaults.GetModelName(); got != "gemini" {
+		t.Fatalf("GetModelName() = %q, want %q", got, "gemini")
+	}
+	if len(cfg.ModelList) != 1 {
+		t.Fatalf("len(ModelList) = %d, want 1", len(cfg.ModelList))
+	}
+	if cfg.ModelList[0].ModelName != "gemini" {
+		t.Fatalf("ModelList[0].ModelName = %q, want %q", cfg.ModelList[0].ModelName, "gemini")
+	}
+	if cfg.ModelList[0].Model != "gemini/gemini-pro" {
+		t.Fatalf("ModelList[0].Model = %q, want %q", cfg.ModelList[0].Model, "gemini/gemini-pro")
+	}
+
+	modelCfg, err := cfg.GetModelConfig(cfg.Agents.Defaults.GetModelName())
+	if err != nil {
+		t.Fatalf("GetModelConfig() error = %v", err)
+	}
+	if modelCfg.Model != "gemini/gemini-pro" {
+		t.Fatalf("modelCfg.Model = %q, want %q", modelCfg.Model, "gemini/gemini-pro")
+	}
+}
+
+func TestLoadConfig_LegacyProvidersConfigKeepsExplicitLegacyModel(t *testing.T) {
+	tmpDir := t.TempDir()
+	configPath := filepath.Join(tmpDir, "config.json")
+	configJSON := `{
+  "agents": {
+    "defaults": {
+      "model": "gemini-pro"
+    }
+  },
+  "providers": {
+    "gemini": {
+      "api_key": "gemini-test-key"
+    }
+  }
+}`
+	if err := os.WriteFile(configPath, []byte(configJSON), 0o600); err != nil {
+		t.Fatalf("os.WriteFile() error: %v", err)
+	}
+
+	cfg, err := LoadConfig(configPath)
+	if err != nil {
+		t.Fatalf("LoadConfig() error: %v", err)
+	}
+
+	if got := cfg.Agents.Defaults.GetModelName(); got != "gemini-pro" {
+		t.Fatalf("GetModelName() = %q, want %q", got, "gemini-pro")
+	}
+
+	modelCfg, err := cfg.GetModelConfig(cfg.Agents.Defaults.GetModelName())
+	if err != nil {
+		t.Fatalf("GetModelConfig() error = %v", err)
+	}
+	if modelCfg.Model != "gemini/gemini-pro" {
+		t.Fatalf("modelCfg.Model = %q, want %q", modelCfg.Model, "gemini/gemini-pro")
+	}
+}
+
 // TestDefaultConfig_DMScope verifies the default dm_scope value
 // TestDefaultConfig_SummarizationThresholds verifies summarization defaults
 func TestDefaultConfig_SummarizationThresholds(t *testing.T) {

pkg/providers/factory_test.go

@@ -1,6 +1,8 @@
 package providers
 
 import (
+	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 
@@ -268,6 +270,37 @@ func TestCreateProviderReturnsHTTPProviderForOpenRouter(t *testing.T) {
 	}
 }
 
+func TestCreateProviderWithLegacyGeminiProvidersConfig(t *testing.T) {
+	tmpDir := t.TempDir()
+	configPath := filepath.Join(tmpDir, "config.json")
+	configJSON := `{
+  "providers": {
+    "gemini": {
+      "api_key": "gemini-test-key"
+    }
+  }
+}`
+	if err := os.WriteFile(configPath, []byte(configJSON), 0o600); err != nil {
+		t.Fatalf("WriteFile() error = %v", err)
+	}
+
+	cfg, err := config.LoadConfig(configPath)
+	if err != nil {
+		t.Fatalf("LoadConfig() error = %v", err)
+	}
+
+	provider, modelID, err := CreateProvider(cfg)
+	if err != nil {
+		t.Fatalf("CreateProvider() error = %v", err)
+	}
+	if _, ok := provider.(*HTTPProvider); !ok {
+		t.Fatalf("provider type = %T, want *HTTPProvider", provider)
+	}
+	if modelID != "gemini-pro" {
+		t.Fatalf("modelID = %q, want %q", modelID, "gemini-pro")
+	}
+}
+
 func TestCreateProviderReturnsCodexCliProviderForCodexCode(t *testing.T) {
 	cfg := config.DefaultConfig()
 	cfg.Agents.Defaults.Model = "test-codex"