feat(import): route MLX TTS models to mlx-audio (#11267)

Detect text-to-speech MLX repositories during model import and emit a TTS-ready mlx-audio configuration. Expose mlx-audio in the backend preference dropdown for repositories without complete metadata.

Assisted-by: Codex:gpt-5

Co-authored-by: localai-org-maint-bot <306269227+localai-org-maint-bot@users.noreply.github.com>

core/gallery/importers/mlx.go

@@ -3,6 +3,7 @@ package importers
 import (
 	"encoding/json"
 	"path/filepath"
+	"slices"
 	"strings"
 
 	"github.com/mudler/LocalAI/core/config"
@@ -31,7 +32,7 @@ func (i *MLXImporter) Match(details Details) bool {
 	}
 
 	b, ok := preferencesMap["backend"].(string)
-	if ok && b == "mlx" || b == "mlx-vlm" {
+	if ok && slices.Contains([]string{"mlx", "mlx-vlm", "mlx-audio"}, b) {
 		return true
 	}
 
@@ -71,19 +72,32 @@ func (i *MLXImporter) Import(details Details) (gallery.ModelConfig, error) {
 	// (issue #10269). Send them to the mlx-vlm backend, which applies the
 	// processor-aware chat template.
 	backend := "mlx"
-	if details.HuggingFace != nil && details.HuggingFace.PipelineTag == "image-text-to-text" {
-		backend = "mlx-vlm"
+	usecases := []string{config.UsecaseChat}
+	useTokenizerTemplate := true
+	if details.HuggingFace != nil {
+		switch details.HuggingFace.PipelineTag {
+		case "image-text-to-text":
+			backend = "mlx-vlm"
+		case "text-to-speech":
+			backend = "mlx-audio"
+			usecases = []string{config.UsecaseTTS}
+			useTokenizerTemplate = false
+		}
 	}
 	// An explicit backend preference always wins.
 	b, ok := preferencesMap["backend"].(string)
 	if ok {
 		backend = b
+		if backend == "mlx-audio" {
+			usecases = []string{config.UsecaseTTS}
+			useTokenizerTemplate = false
+		}
 	}
 
 	modelConfig := config.ModelConfig{
 		Name:                name,
 		Description:         description,
-		KnownUsecaseStrings: []string{config.UsecaseChat},
+		KnownUsecaseStrings: usecases,
 		Backend:             backend,
 		PredictionOptions: schema.PredictionOptions{
 			BasicModelRequest: schema.BasicModelRequest{
@@ -91,7 +105,7 @@ func (i *MLXImporter) Import(details Details) (gallery.ModelConfig, error) {
 			},
 		},
 		TemplateConfig: config.TemplateConfig{
-			UseTokenizerTemplate: true,
+			UseTokenizerTemplate: useTokenizerTemplate,
 		},
 	}
 

core/gallery/importers/mlx_test.go

@@ -48,6 +48,16 @@ var _ = Describe("MLXImporter", func() {
 			Expect(result).To(BeTrue())
 		})
 
+		It("should match when backend preference is mlx-audio", func() {
+			preferences := json.RawMessage(`{"backend": "mlx-audio"}`)
+			details := importers.Details{
+				URI:         "https://example.com/model",
+				Preferences: preferences,
+			}
+
+			Expect(importer.Match(details)).To(BeTrue())
+		})
+
 		It("should not match when URI does not contain mlx-community/ and no backend preference", func() {
 			details := importers.Details{
 				URI: "https://huggingface.co/other-org/test-model",
@@ -123,6 +133,21 @@ var _ = Describe("MLXImporter", func() {
 			Expect(modelConfig.ConfigFile).To(ContainSubstring("backend: mlx-vlm"))
 		})
 
+		It("should configure explicit mlx-audio imports for text-to-speech", func() {
+			preferences := json.RawMessage(`{"backend": "mlx-audio"}`)
+			details := importers.Details{
+				URI:         "https://huggingface.co/mlx-community/Kokoro-82M-4bit",
+				Preferences: preferences,
+			}
+
+			modelConfig, err := importer.Import(details)
+
+			Expect(err).ToNot(HaveOccurred())
+			Expect(modelConfig.ConfigFile).To(ContainSubstring("backend: mlx-audio"))
+			Expect(modelConfig.ConfigFile).To(ContainSubstring("- tts"))
+			Expect(modelConfig.ConfigFile).ToNot(ContainSubstring("use_tokenizer_template: true"))
+		})
+
 		It("should auto-route vision-language models to the mlx-vlm backend", func() {
 			// gemma-4 E4B and similar VLMs declare pipeline_tag
 			// "image-text-to-text" on HuggingFace. The text-only mlx-lm
@@ -143,6 +168,23 @@ var _ = Describe("MLXImporter", func() {
 			Expect(modelConfig.ConfigFile).To(ContainSubstring("backend: mlx-vlm"))
 		})
 
+		It("should auto-route text-to-speech models to the mlx-audio backend", func() {
+			details := importers.Details{
+				URI: "https://huggingface.co/mlx-community/Kokoro-82M-4bit",
+				HuggingFace: &hfapi.ModelDetails{
+					ModelID:     "mlx-community/Kokoro-82M-4bit",
+					PipelineTag: "text-to-speech",
+				},
+			}
+
+			modelConfig, err := importer.Import(details)
+
+			Expect(err).ToNot(HaveOccurred())
+			Expect(modelConfig.ConfigFile).To(ContainSubstring("backend: mlx-audio"))
+			Expect(modelConfig.ConfigFile).To(ContainSubstring("- tts"))
+			Expect(modelConfig.ConfigFile).ToNot(ContainSubstring("use_tokenizer_template: true"))
+		})
+
 		It("should keep text-only models on the plain mlx backend", func() {
 			details := importers.Details{
 				URI: "https://huggingface.co/mlx-community/Llama-3.2-1B-Instruct-4bit",

core/http/endpoints/localai/backend.go

@@ -38,6 +38,7 @@ var knownPrefOnlyBackends = []schema.KnownBackend{
 	{Name: "whisperx", Modality: "asr", AutoDetect: false, Description: "WhisperX transcription (preference-only)"},
 	{Name: "crispasr", Modality: "asr", AutoDetect: false, Description: "CrispASR multi-architecture transcription (preference-only)"},
 	// TTS
+	{Name: "mlx-audio", Modality: "tts", AutoDetect: false, Description: "MLX-Audio text-to-speech models (auto-detected; pref-only fallback)"},
 	{Name: "kokoros", Modality: "tts", AutoDetect: false, Description: "Kokoros TTS (preference-only)"},
 	{Name: "qwen-tts", Modality: "tts", AutoDetect: false, Description: "Qwen TTS (preference-only)"},
 	{Name: "qwen3-tts-cpp", Modality: "tts", AutoDetect: false, Description: "Qwen3 TTS C++ (preference-only)"},

core/http/endpoints/localai/backend_test.go

@@ -152,6 +152,7 @@ var _ = Describe("Backend Endpoints", func() {
 			expectPrefOnly("tinygrad", "text")
 			expectPrefOnly("trl", "text")
 			expectPrefOnly("mlx-vlm", "text")
+			expectPrefOnly("mlx-audio", "tts")
 			expectPrefOnly("whisperx", "asr")
 			expectPrefOnly("crispasr", "asr")
 			expectPrefOnly("kokoros", "tts")

docs/content/getting-started/models.md

@@ -80,6 +80,12 @@ The WebUI provides a powerful model import interface that supports both simple a
    - Custom preferences
 5. Click "Import Model" to start the import process
 
+Repositories under `mlx-community` are imported with the native MLX backend.
+LocalAI uses Hugging Face's pipeline metadata to select `mlx-vlm` for
+vision-language models and `mlx-audio` for text-to-speech models; other MLX
+repositories use `mlx`. An explicit backend selection in the import form always
+overrides this automatic routing.
+
 ### Advanced Import Mode
 
 For full control over model configuration: