feat(realtime): stream the LLM / TTS / transcription pipeline stages (#10176)

* feat(realtime): pipeline streaming + disable_thinking config Add a nested pipeline.streaming.{llm,tts,transcription} block plus pipeline.disable_thinking, with StreamLLM/StreamTTS/StreamTranscription/ ThinkingDisabled helpers. Pointer-bools so unset keeps the unary path; existing configs are unaffected. Wiring into the realtime handler follows. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): sentence segmenter for streamed LLM->TTS pipelining streamSegmenter accumulates streamed LLM tokens and emits complete sentence/clause segments (terminator+whitespace, or newline) so TTS can synthesize each segment as it completes instead of waiting for the whole reply. Pure helper; the streaming handler wiring consumes it next. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): streaming TTS/transcription methods on Model interface Add TTSStream and TranscribeStream to the realtime Model interface and implement them on wrappedModel (delegating to backend.ModelTTSStream / ModelTranscriptionStream) and transcriptOnlyModel. ttsStream adapts the backend's WAV-framed stream (44-byte header carrying the sample rate, then PCM) into raw PCM + sample rate for the realtime transports. Handler wiring that consumes these (flag-gated) follows. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): emitSpeech with flag-gated streaming TTS emitSpeech synthesizes a piece of text and forwards audio to the client, streaming one output_audio.delta per backend PCM chunk when the pipeline sets streaming.tts, or one delta for the whole utterance otherwise. WebRTC gets raw PCM (it resamples internally); WebSocket gets base64 PCM at the session rate. It emits no transcript/audio-done events so a streamed reply can be split into multiple spoken segments sharing one response. Adds fakeModel/fakeTransport test doubles for the realtime Model/Transport interfaces, driving streaming assertions deterministically. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): route response audio through emitSpeech (streaming TTS) Replace the inline unary TTS block in the response handler with emitSpeech, which streams a response.output_audio.delta per backend PCM chunk when pipeline.streaming.tts is set and otherwise preserves the single-delta unary behaviour. emitSpeech returns the accumulated base64 audio, stored on the conversation item as before. Transcript and audio-done events stay in the handler so later per-segment streaming can reuse emitSpeech. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): streaming transcription text deltas Add emitTranscription and route commitUtterance through it. With pipeline.streaming.transcription set it streams each transcript fragment as a conversation.item.input_audio_transcription.delta via TranscribeStream then a completed event; otherwise it preserves the single completed-event unary behaviour. Returns the final transcript for response generation. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): pipeline disable_thinking maps to enable_thinking off applyPipelineThinking forces the LLM's ReasoningConfig.DisableReasoning when pipeline.disable_thinking is set, which gRPCPredictOpts turns into the enable_thinking=false backend metadata. Applied at newModel construction on the per-session LLM config copy, so it doesn't leak to other model users and needs no realtime-specific request plumbing. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): speechStreamer for token-streamed LLM->TTS emitSpeech now returns raw PCM (caller base64-encodes) so streamed segments accumulate correctly. speechStreamer consumes streamed LLM tokens: it strips reasoning via the streaming ReasoningExtractor, emits a transcript delta per content fragment, and sentence-pipes content into emitSpeech so each sentence is synthesized as soon as it's ready. Handler wiring (plain-content turns) follows. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): wire streamLLMResponse for token-streamed replies triggerResponseAtTurn takes a streamed path when pipeline.streaming.llm is set, the turn has no tools, and audio is requested: streamLLMResponse announces the assistant item, drives the LLM token callback through a speechStreamer (reasoning-stripped transcript deltas + sentence-piped TTS), and emits the terminal events. Tool turns and non-streaming pipelines keep the existing buffered path unchanged, so this is strictly opt-in. Assisted-by: Claude:claude-opus-4-8 go vet Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * docs(realtime): document pipeline streaming + disable_thinking Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * fix(realtime): register pipeline streaming/thinking config fields TestAllFieldsHaveRegistryEntries (core/config/meta) requires every config field to have a meta registry entry. The four new pipeline fields (disable_thinking, streaming.{llm,tts,transcription}) had none, failing tests-linux/tests-apple. Add toggle entries for them. Also handle the os.Remove return in realtime_speech_test.go to satisfy errcheck (golangci-lint). Assisted-by: Claude:claude-opus-4-8 go test, golangci-lint Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * fix(realtime): always strip reasoning from spoken output disable_thinking maps to ReasoningConfig.DisableReasoning=true on the LLM config, which the backend reads as enable_thinking=false. But the realtime handler reads that SAME config to drive reasoning extraction, and there DisableReasoning=true means "skip stripping". PredictConfig() returns this LLM config, so both the streamed (speechStreamer) and buffered realtime paths stopped stripping <think>…</think> exactly when disable_thinking was on — leaking raw reasoning to the client whenever the model ignored the enable_thinking hint (e.g. lfm2.5). Add spokenReasoningConfig() which clears DisableReasoning for extraction (keeping custom tokens/tag pairs) and route both realtime paths through it. Spoken output now always strips reasoning, independent of the backend suppression hint. Assisted-by: Claude:claude-opus-4-8 go test, golangci-lint Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * fix(realtime): clean TTS temp path before read (gosec G304) emitSpeech reads the WAV file the TTS backend wrote. The read moved here from realtime.go, so code-scanning flagged it as a new G304 alert even though the path is backend-controlled (a temp file), not user input. Wrap it in filepath.Clean — a real path normalization that also clears the alert, keeping with the repo's no-#nosec convention. Assisted-by: Claude:claude-opus-4-8 gosec, golangci-lint Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * refactor(realtime): buffer whole message for TTS, drop sentence segmenter Per review (richiejp): the sentence segmenter pipelined unary TTS by splitting on ASCII .!?/newline, which does nothing for languages without those boundaries (CJK/Thai) — there it already degraded to buffering the whole message anyway. Replace it with a uniform model: stream the LLM transcript live, buffer the full message, then synthesize it once. emitSpeech already streams the audio chunks when the backend implements TTSStream and falls back to a single unary delta otherwise, so this is real streaming TTS where supported and a clean whole-message synthesis elsewhere — no per-sentence emulation, no language assumptions. speechStreamer becomes transcriptStreamer (transcript deltas only); the whole-message synthesis moves into streamLLMResponse. Assisted-by: Claude:claude-opus-4-8 go test, golangci-lint Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): stream tool-call turns via tokenizer-template autoparser Per review (richiejp): tool-call deltas exist, so streaming should work with tools too. It does — for models that use their tokenizer template. The C++ autoparser then clears reply.Message and delivers content + tool calls via ChatDeltas, so the streamed transcript carries only spoken content (no tool-call JSON leak) and the tool calls are parsed from the final response. - Drop the len(tools)==0 gate; stream when no tools OR use_tokenizer_template (grammar-based function calling still buffers, since its call is emitted as JSON in the token stream and would leak into the transcript). - streamLLMResponse takes tools/toolChoice/toolTurn, reads ChatDelta content in the token callback, parses tool calls from the final ChatDeltas, and creates the assistant content item lazily so a content-less tool turn emits only the tool calls. - Extract emitToolCallItems from the buffered path so both paths finalize tool calls, response.done, and server-side assistant-tool follow-ups identically. Assisted-by: Claude:claude-opus-4-8 go test, golangci-lint Signed-off-by: Ettore Di Giacinto <mudler@localai.io> * feat(realtime): script-aware clause chunking + streamed-reply fixes Opt-in pipeline.streaming.clause_chunking splits the streamed LLM reply into speakable clauses and synthesizes each as soon as it completes, lowering time-to-first-audio instead of buffering the whole message. The splitter is script-aware (rivo/uniseg, pure Go): UAX#29 sentence segmentation handles CJK 。！？ with no whitespace, CJK clause punctuation (，、；：) and Thai/Lao spaces give finer cuts, and a UAX#14 line-break cap bounds an over-long punctuation-less run. Unlike the old ASCII .!?/newline segmenter (dropped in 076dcdbe) it does not degrade to whole-message buffering for CJK/Thai; scripts needing a dictionary (Khmer/Burmese) stay buffered until a space or end-of-message. Clauses are synthesized synchronously in the token callback (the LLM keeps generating into the gRPC stream meanwhile), so audio still starts mid-generation. Off by default — the whole-message path is unchanged. Also fix the streamed-reply path and the Talk page: - Don't swallow streamed autoparser content as reasoning: the tokenizer-template path already delivers reasoning-free content via ChatDeltas, so prefilling the thinking start token re-tagged it as an unclosed reasoning block, leaving no spoken reply. Disable the prefill on that path; closed tag pairs are still stripped (#9985). - Generate collision-free realtime IDs (16 random bytes) instead of a constant, so per-item bookkeeping (cancel, conversation.item.retrieve) works. - Key the Talk transcript by the server item_id and upsert entries. Realtime events arrive over a WebRTC data channel — outside React's event system — so React defers the setTranscript updaters while synchronous ref writes in handler bodies run first; the old index-tracking ref rendered a duplicate assistant bubble on completion. Upserts by item_id are idempotent and order-independent. - Drop the partial assistant bubble on a cancelled response (barge-in): the server discards the interrupted item and sends response.done with status "cancelled"; mirror that in the UI so the regenerated reply isn't rendered as a second assistant message. Assisted-by: Claude:claude-opus-4-8 [Claude Code] Assisted-by: Claude:claude-fable-5 [Claude Code] Signed-off-by: Richard Palethorpe <io@richiejp.com> --------- Signed-off-by: Ettore Di Giacinto <mudler@localai.io> Signed-off-by: Richard Palethorpe <io@richiejp.com> Co-authored-by: Ettore Di Giacinto <mudler@localai.io> Co-authored-by: Richard Palethorpe <io@richiejp.com>
2026-06-11 18:27:32 -04:00 · 2026-06-11 09:43:12 +02:00
parent 228a6dfe79
commit 892fc49949
19 changed files with 1716 additions and 128 deletions
--- a/core/config/meta/registry.go
+++ b/core/config/meta/registry.go
@@ -308,6 +308,41 @@ func DefaultRegistry() map[string]FieldMetaOverride {
 			},
 			Order: 64,
 		},
+		"pipeline.disable_thinking": {
+			Section:     "pipeline",
+			Label:       "Disable Thinking",
+			Description: "Suppress reasoning/thinking output from the pipeline LLM (sets enable_thinking=false on the underlying model). Use for models that emit <think> blocks you don't want spoken or streamed back to the realtime client.",
+			Component:   "toggle",
+			Order:       65,
+		},
+		"pipeline.streaming.llm": {
+			Section:     "pipeline",
+			Label:       "Stream LLM",
+			Description: "Stream LLM tokens to the realtime client as they are generated instead of waiting for the full response. Emits incremental response.output_audio_transcript.delta / text deltas.",
+			Component:   "toggle",
+			Order:       66,
+		},
+		"pipeline.streaming.tts": {
+			Section:     "pipeline",
+			Label:       "Stream TTS",
+			Description: "Stream synthesized audio chunks to the realtime client as they are produced (requires a TTS backend that implements TTSStream). Falls back to unary synthesis otherwise.",
+			Component:   "toggle",
+			Order:       67,
+		},
+		"pipeline.streaming.transcription": {
+			Section:     "pipeline",
+			Label:       "Stream Transcription",
+			Description: "Stream partial transcription text to the realtime client as the STT backend produces it (requires a transcription backend that implements AudioTranscriptionStream). Falls back to unary transcription otherwise.",
+			Component:   "toggle",
+			Order:       68,
+		},
+		"pipeline.streaming.clause_chunking": {
+			Section:     "pipeline",
+			Label:       "Clause Chunking",
+			Description: "Split the streamed reply into speakable clauses and synthesize each as soon as it completes, instead of buffering the whole message before TTS — lower time-to-first-audio. Script-aware (handles CJK 。！？ and Thai/Lao spaces), so it does not whitespace-split. Requires Stream LLM; off buffers the whole message.",
+			Component:   "toggle",
+			Order:       69,
+		},

 		// --- Functions ---
 		"function.grammar.parallel_calls": {
--- a/core/config/model_config.go
+++ b/core/config/model_config.go
@@ -499,6 +499,16 @@ type Pipeline struct {
 	// the pipeline's LLM without editing the LLM model config. Overrides the LLM's
 	// own reasoning_effort. Unset leaves the LLM model config in charge.
 	ReasoningEffort string `yaml:"reasoning_effort,omitempty" json:"reasoning_effort,omitempty"`
+
+	// Streaming opts each pipeline stage into incremental delivery (LLM tokens,
+	// TTS audio chunks, transcription text). Unset stages keep the blocking
+	// unary path, so existing configs are unaffected.
+	Streaming PipelineStreaming `yaml:"streaming,omitempty" json:"streaming,omitempty"`
+
+	// DisableThinking suppresses reasoning/thinking for the pipeline LLM (maps
+	// to enable_thinking=false backend metadata) without editing the underlying
+	// LLM model config. Unset leaves the LLM model config in charge.
+	DisableThinking *bool `yaml:"disable_thinking,omitempty" json:"disable_thinking,omitempty"`
 }

 // ApplyReasoningEffort resolves the effective reasoning effort — a per-request
@@ -530,6 +540,41 @@ func (c *ModelConfig) ApplyReasoningEffort(requestEffort string) {
 	}
 }

+// @Description PipelineStreaming toggles incremental delivery per realtime stage.
+type PipelineStreaming struct {
+	LLM           *bool `yaml:"llm,omitempty" json:"llm,omitempty"`
+	TTS           *bool `yaml:"tts,omitempty" json:"tts,omitempty"`
+	Transcription *bool `yaml:"transcription,omitempty" json:"transcription,omitempty"`
+	// ClauseChunking splits the streamed LLM reply into speakable clauses and
+	// synthesizes each as soon as it completes, instead of buffering the whole
+	// message before TTS. Script-aware (CJK/Thai), so it does not rely on
+	// whitespace sentence boundaries. Requires LLM streaming; unset buffers the
+	// whole message (today's default).
+	ClauseChunking *bool `yaml:"clause_chunking,omitempty" json:"clause_chunking,omitempty"`
+}
+
+// StreamLLM reports whether LLM tokens should be streamed for this pipeline.
+func (p Pipeline) StreamLLM() bool { return p.Streaming.LLM != nil && *p.Streaming.LLM }
+
+// StreamTTS reports whether TTS audio should be streamed for this pipeline.
+func (p Pipeline) StreamTTS() bool { return p.Streaming.TTS != nil && *p.Streaming.TTS }
+
+// StreamTranscription reports whether transcription text should be streamed.
+func (p Pipeline) StreamTranscription() bool {
+	return p.Streaming.Transcription != nil && *p.Streaming.Transcription
+}
+
+// ChunkClauses reports whether the streamed reply should be split into
+// script-aware clauses and synthesized incrementally rather than buffered whole.
+func (p Pipeline) ChunkClauses() bool {
+	return p.Streaming.ClauseChunking != nil && *p.Streaming.ClauseChunking
+}
+
+// ThinkingDisabled reports whether the pipeline forces the LLM's thinking off.
+func (p Pipeline) ThinkingDisabled() bool {
+	return p.DisableThinking != nil && *p.DisableThinking
+}
+
 // @Description File configuration for model downloads
 type File struct {
 	Filename string         `yaml:"filename,omitempty" json:"filename,omitempty"`
--- a/core/config/pipeline_streaming_test.go
+++ b/core/config/pipeline_streaming_test.go
@@ -0,0 +1,57 @@
+package config
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	"gopkg.in/yaml.v3"
+)
+
+// The realtime pipeline can stream each stage (LLM tokens, TTS audio,
+// transcription text) and can disable model "thinking" for the LLM. These are
+// opt-in per pipeline; everything defaults to off so existing configs keep the
+// unary behaviour.
+var _ = Describe("Pipeline streaming config", func() {
+	It("defaults every streaming + thinking helper to false when unset", func() {
+		var p Pipeline
+		Expect(p.StreamLLM()).To(BeFalse())
+		Expect(p.StreamTTS()).To(BeFalse())
+		Expect(p.StreamTranscription()).To(BeFalse())
+		Expect(p.ChunkClauses()).To(BeFalse())
+		Expect(p.ThinkingDisabled()).To(BeFalse())
+	})
+
+	It("parses the nested streaming block and disable_thinking from YAML", func() {
+		var c ModelConfig
+		err := yaml.Unmarshal([]byte(`
+name: gpt-realtime
+pipeline:
+  llm: my-llm
+  tts: my-tts
+  transcription: my-stt
+  streaming:
+    llm: true
+    tts: true
+    transcription: true
+    clause_chunking: true
+  disable_thinking: true
+`), &c)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(c.Pipeline.StreamLLM()).To(BeTrue())
+		Expect(c.Pipeline.StreamTTS()).To(BeTrue())
+		Expect(c.Pipeline.StreamTranscription()).To(BeTrue())
+		Expect(c.Pipeline.ChunkClauses()).To(BeTrue())
+		Expect(c.Pipeline.ThinkingDisabled()).To(BeTrue())
+	})
+
+	It("treats an explicit false in the streaming block as disabled", func() {
+		var c ModelConfig
+		err := yaml.Unmarshal([]byte(`
+name: gpt-realtime
+pipeline:
+  streaming:
+    tts: false
+`), &c)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(c.Pipeline.StreamTTS()).To(BeFalse())
+	})
+})
--- a/core/http/endpoints/openai/realtime.go
+++ b/core/http/endpoints/openai/realtime.go
@@ -2,8 +2,10 @@ package openai

 import (
 	"context"
+	"crypto/rand"
 	"encoding/base64"
 	"encoding/binary"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"math"
@@ -235,6 +237,12 @@ type Model interface {
 	Transcribe(ctx context.Context, audio, language string, translate bool, diarize bool, prompt string) (*schema.TranscriptionResult, error)
 	Predict(ctx context.Context, messages schema.Messages, images, videos, audios []string, tokenCallback func(string, backend.TokenUsage) bool, tools []types.ToolUnion, toolChoice *types.ToolChoiceUnion, logprobs *int, topLogprobs *int, logitBias map[string]float64) (func() (backend.LLMResponse, error), error)
 	TTS(ctx context.Context, text, voice, language string) (string, *proto.Result, error)
+	// TTSStream synthesizes speech incrementally, invoking onAudio with raw PCM
+	// chunks (and the backend sample rate) as they are produced.
+	TTSStream(ctx context.Context, text, voice, language string, onAudio func(pcm []byte, sampleRate int) error) error
+	// TranscribeStream transcribes audio incrementally, invoking onDelta for each
+	// transcript text fragment and returning the final aggregated result.
+	TranscribeStream(ctx context.Context, audio, language string, translate, diarize bool, prompt string, onDelta func(text string)) (*schema.TranscriptionResult, error)
 	PredictConfig() *config.ModelConfig
 }

@@ -1254,27 +1262,15 @@ func commitUtterance(ctx context.Context, utt []byte, session *Session, conv *Co
 	// TODO: If we have a real any-to-any model then transcription is optional
 	var transcript string
 	if session.InputAudioTranscription != nil {
-		tr, err := session.ModelInterface.Transcribe(ctx, f.Name(), session.InputAudioTranscription.Language, false, false, session.InputAudioTranscription.Prompt)
+		// emitTranscription streams transcript deltas when
+		// pipeline.streaming.transcription is set, otherwise emits a single
+		// completed event; either way it returns the final transcript text.
+		var err error
+		transcript, err = emitTranscription(ctx, t, session, generateItemID(), f.Name())
 		if err != nil {
 			sendError(t, "transcription_failed", err.Error(), "", "event_TODO")
 			return
-		} else if tr == nil {
-			sendError(t, "transcription_failed", "trancribe result is nil", "", "event_TODO")
-			return
 		}
-
-		transcript = tr.Text
-		sendEvent(t, types.ConversationItemInputAudioTranscriptionCompletedEvent{
-			ServerEventBase: types.ServerEventBase{
-				EventID: "event_TODO",
-			},
-
-			ItemID: generateItemID(),
-			// ResponseID:   "resp_TODO", // Not needed for transcription completed event
-			// OutputIndex:  0,
-			ContentIndex: 0,
-			Transcript:   transcript,
-		})
 	} else {
 		sendNotImplemented(t, "any-to-any models")
 		return
@@ -1502,6 +1498,26 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 		},
 	})

+	// Streamed LLM path: when the pipeline opts into LLM streaming, stream the
+	// transcript to the client as it is generated and synthesize the buffered
+	// message once. Tool turns are supported only when the model uses its
+	// tokenizer template: the C++ autoparser then delivers content and tool
+	// calls via ChatDeltas (clearing the text stream), so the spoken transcript
+	// never leaks tool-call tokens. Grammar-based function calling emits the
+	// call as JSON in the token stream, so those turns keep the buffered path.
+	if config != nil && session.ModelConfig != nil && session.ModelConfig.Pipeline.StreamLLM() {
+		canStream := len(tools) == 0 || config.TemplateConfig.UseTokenizerTemplate
+		var respMods []types.Modality
+		if overrides != nil {
+			respMods = overrides.OutputModalities
+		}
+		if canStream && modalitiesContainAudio(resolveOutputModalities(session.OutputModalities, respMods)) {
+			if streamLLMResponse(ctx, session, conv, t, responseID, conversationHistory, images, config, tools, toolChoice, toolTurn) {
+				return
+			}
+		}
+	}
+
 	predFunc, err := session.ModelInterface.Predict(ctx, conversationHistory, images, nil, nil, nil, tools, toolChoice, nil, nil, nil)
 	if err != nil {
 		sendError(t, "inference_failed", fmt.Sprintf("backend error: %v", err), "", "") // item.Assistant.ID is unknown here
@@ -1579,7 +1595,7 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 		// ExtractReasoningWithConfig is a no-op when no tag pair matches,
 		// so it's safe to apply unconditionally in the no-reasoning branch.
 		if deltaReasoning == "" && deltaContent != "" {
-			deltaReasoning, deltaContent = reasoning.ExtractReasoningComplete(deltaContent, thinkingStartToken, config.ReasoningConfig)
+			deltaReasoning, deltaContent = reasoning.ExtractReasoningComplete(deltaContent, thinkingStartToken, spokenReasoningConfig(config.ReasoningConfig))
 		}
 		reasoningText = deltaReasoning
 		responseWithoutReasoning = deltaContent
@@ -1587,7 +1603,7 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 		cleanedResponse = deltaContent
 		toolCalls = deltaToolCalls
 	} else {
-		reasoningText, responseWithoutReasoning = reasoning.ExtractReasoningComplete(rawResponse, thinkingStartToken, config.ReasoningConfig)
+		reasoningText, responseWithoutReasoning = reasoning.ExtractReasoningComplete(rawResponse, thinkingStartToken, spokenReasoningConfig(config.ReasoningConfig))
 		textContent = functions.ParseTextContent(responseWithoutReasoning, config.FunctionsConfig)
 		cleanedResponse = functions.CleanupLLMResult(responseWithoutReasoning, config.FunctionsConfig)
 		toolCalls = functions.ParseFunctionCall(cleanedResponse, config.FunctionsConfig)
@@ -1713,64 +1729,7 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 				return
 			}

-			audioFilePath, res, err := session.ModelInterface.TTS(ctx, finalSpeech, session.Voice, session.InputAudioTranscription.Language)
-			if err != nil {
-				if ctx.Err() != nil {
-					xlog.Debug("TTS cancelled (barge-in)")
-					sendCancelledResponse()
-					return
-				}
-				xlog.Error("TTS failed", "error", err)
-				sendError(t, "tts_error", fmt.Sprintf("TTS generation failed: %v", err), "", item.Assistant.ID)
-				return
-			}
-			if !res.Success {
-				xlog.Error("TTS failed", "message", res.Message)
-				sendError(t, "tts_error", fmt.Sprintf("TTS generation failed: %s", res.Message), "", item.Assistant.ID)
-				return
-			}
-			defer func() { _ = os.Remove(audioFilePath) }()
-
-			audioBytes, err := os.ReadFile(audioFilePath)
-			if err != nil {
-				xlog.Error("failed to read TTS file", "error", err)
-				sendError(t, "tts_error", fmt.Sprintf("Failed to read TTS audio: %v", err), "", item.Assistant.ID)
-				return
-			}
-
-			// Parse WAV header to get raw PCM and the actual sample rate from the TTS backend.
-			pcmData, ttsSampleRate := laudio.ParseWAV(audioBytes)
-			if ttsSampleRate == 0 {
-				ttsSampleRate = localSampleRate
-			}
-			xlog.Debug("TTS audio parsed", "raw_bytes", len(audioBytes), "pcm_bytes", len(pcmData), "sample_rate", ttsSampleRate)
-
-			// SendAudio (WebRTC) passes PCM at the TTS sample rate directly to the
-			// Opus encoder, which resamples to 48kHz internally. This avoids a
-			// lossy intermediate resample through 16kHz.
-			// XXX: This is a noop in websocket mode; it's included in the JSON instead
-			if err := t.SendAudio(ctx, pcmData, ttsSampleRate); err != nil {
-				if ctx.Err() != nil {
-					xlog.Debug("Audio playback cancelled (barge-in)")
-					sendCancelledResponse()
-					return
-				}
-				xlog.Error("failed to send audio via transport", "error", err)
-			}
-
-			// For WebSocket clients, resample to the session's output rate and
-			// deliver audio as base64 in JSON events. WebRTC clients already
-			// received audio over the RTP track, so skip the base64 payload.
-			if !isWebRTC {
-				wsPCM := pcmData
-				if ttsSampleRate != session.OutputSampleRate {
-					samples := sound.BytesToInt16sLE(pcmData)
-					resampled := sound.ResampleInt16(samples, ttsSampleRate, session.OutputSampleRate)
-					wsPCM = sound.Int16toBytesLE(resampled)
-				}
-				audioString = base64.StdEncoding.EncodeToString(wsPCM)
-			}
-
+			// Transcript of the spoken reply (the audio's text).
 			sendEvent(t, types.ResponseOutputAudioTranscriptDeltaEvent{
 				ServerEventBase: types.ServerEventBase{},
 				ResponseID:      responseID,
@@ -1788,15 +1747,26 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 				Transcript:      finalSpeech,
 			})

+			// Synthesize and send the audio. With pipeline.streaming.tts enabled
+			// emitSpeech forwards a response.output_audio.delta per backend PCM
+			// chunk as it's produced; otherwise it sends the whole utterance as a
+			// single delta. The returned PCM is stored (base64) on the item below.
+			pcmAudio, err := emitSpeech(ctx, t, session, responseID, item.Assistant.ID, finalSpeech)
+			if err != nil {
+				if ctx.Err() != nil {
+					xlog.Debug("TTS cancelled (barge-in)")
+					sendCancelledResponse()
+					return
+				}
+				xlog.Error("TTS failed", "error", err)
+				sendError(t, "tts_error", fmt.Sprintf("TTS generation failed: %v", err), "", item.Assistant.ID)
+				return
+			}
+			if !isWebRTC {
+				audioString = base64.StdEncoding.EncodeToString(pcmAudio)
+			}
+
 			if !isWebRTC {
-				sendEvent(t, types.ResponseOutputAudioDeltaEvent{
-					ServerEventBase: types.ServerEventBase{},
-					ResponseID:      responseID,
-					ItemID:          item.Assistant.ID,
-					OutputIndex:     0,
-					ContentIndex:    0,
-					Delta:           audioString,
-				})
 				sendEvent(t, types.ResponseOutputAudioDoneEvent{
 					ServerEventBase: types.ServerEventBase{},
 					ResponseID:      responseID,
@@ -1849,17 +1819,27 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 		})
 	}

-	// Handle Tool Calls. Two paths:
-	//   - LocalAI Assistant tools (session.AssistantExecutor.IsTool) run
-	//     server-side; we append both the call and its output to conv.Items
-	//     and re-trigger a follow-up response so the model can speak the
-	//     result. The client only sees observability events.
-	//   - All other tools follow the standard OpenAI flow: emit
-	//     function_call_arguments.done and wait for the client to send
-	//     conversation.item.create back.
-	xlog.Debug("About to handle tool calls", "finalToolCallsCount", len(finalToolCalls))
+	// Emit the parsed tool calls, the terminal response.done, and (for
+	// server-side assistant tools) the follow-up response. Shared with the
+	// streamed path so both finalize tool calls identically.
+	emitToolCallItems(ctx, session, conv, t, responseID, finalToolCalls, finalSpeech != "", toolTurn)
+}
+
+// emitToolCallItems emits the realtime function_call items for the parsed tool
+// calls, the terminal response.done, and — for server-side LocalAI Assistant
+// tools — re-triggers a follow-up response so the model can speak the result.
+// hasContent shifts the tool-call output index past the assistant content item
+// when the same turn also produced spoken/text content. Two tool paths:
+//   - LocalAI Assistant tools (session.AssistantExecutor.IsTool) run server-side;
+//     we append both the call and its output to conv.Items and re-trigger. The
+//     client only sees observability events.
+//   - All other tools follow the standard OpenAI flow: emit
+//     function_call_arguments.done and wait for the client to send
+//     conversation.item.create back.
+func emitToolCallItems(ctx context.Context, session *Session, conv *Conversation, t Transport, responseID string, toolCalls []functions.FuncCallResults, hasContent bool, toolTurn int) {
+	xlog.Debug("About to handle tool calls", "finalToolCallsCount", len(toolCalls))
 	executedAssistantTool := false
-	for i, tc := range finalToolCalls {
+	for i, tc := range toolCalls {
 		toolCallID := generateItemID()
 		callID := "call_" + generateUniqueID() // OpenAI uses call_xyz

@@ -1879,7 +1859,7 @@ func triggerResponseAtTurn(ctx context.Context, session *Session, conv *Conversa
 		conv.Lock.Unlock()

 		outputIndex := i
-		if finalSpeech != "" {
+		if hasContent {
 			outputIndex++
 		}

@@ -2005,8 +1985,11 @@ func generateItemID() string {
 }

 func generateUniqueID() string {
-	// Generate a unique ID string
-	// For simplicity, use a counter or UUID
-	// Implement as needed
-	return "unique_id"
+	// 16 random bytes, hex-encoded. Must be collision-free: session, item,
+	// response and call IDs build on this, and the conversation tracks/removes
+	// items by ID (e.g. cancel() in realtime_stream.go, conversation.item.retrieve).
+	// A constant would make every ID alias and corrupt that bookkeeping.
+	var b [16]byte
+	_, _ = rand.Read(b[:])
+	return hex.EncodeToString(b[:])
 }
--- a/core/http/endpoints/openai/realtime_chunker.go
+++ b/core/http/endpoints/openai/realtime_chunker.go
@@ -0,0 +1,200 @@
+package openai
+
+import (
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/rivo/uniseg"
+)
+
+// Default clause-chunker bounds (in runes). minRunes gates only sub-sentence
+// (clause-mark / Thai-space) cuts so we don't synthesize tiny choppy fragments;
+// full sentences always flush regardless of length. maxRunes caps an
+// unterminated run so a long punctuation-less span doesn't buffer unbounded.
+const (
+	defaultClauseMinRunes = 12
+	defaultClauseMaxRunes = 200
+)
+
+// clauseChunker splits streamed LLM content into speakable clauses for
+// incremental TTS, in a SCRIPT-AWARE way so it works for languages without
+// whitespace word boundaries. It leans on UAX #29 sentence segmentation (which
+// natively terminates on CJK 。！？ as well as Latin .!?), adds CJK clause
+// punctuation (，、；：) and Thai/Lao spaces as finer boundaries, and caps an
+// over-long unterminated run via UAX #14 line-break opportunities.
+//
+// Unlike the old ASCII .!?/newline segmenter (dropped in 076dcdbe), it does not
+// degrade to whole-message buffering for CJK (handled natively) or Thai/Lao
+// (handled via spaces, which Thai uses at clause/sentence boundaries). Scripts
+// that genuinely need a dictionary (Khmer/Myanmar) simply stay buffered until a
+// space or end-of-message — no worse than the buffered default.
+//
+// It is not safe for concurrent use; callers feed it from a single goroutine
+// (the LLM token callback).
+type clauseChunker struct {
+	buf      strings.Builder
+	minRunes int
+	maxRunes int
+}
+
+func newClauseChunker(minRunes, maxRunes int) *clauseChunker {
+	return &clauseChunker{minRunes: minRunes, maxRunes: maxRunes}
+}
+
+// push appends streamed content and returns any clauses that are now complete —
+// "complete" meaning confirmed by following content, so we never speak a clause
+// that the next token might extend. Incomplete trailing text stays buffered.
+func (c *clauseChunker) push(text string) []string {
+	c.buf.WriteString(text)
+	return c.drain(false)
+}
+
+// flush returns the remaining buffered clauses, treating end-of-input as a hard
+// boundary, and clears the buffer.
+func (c *clauseChunker) flush() []string {
+	return c.drain(true)
+}
+
+func (c *clauseChunker) drain(final bool) []string {
+	s := c.buf.String()
+	rest := s
+	var out []string
+	for rest != "" {
+		end, ok := c.nextBoundary(rest, final)
+		if !ok {
+			break
+		}
+		if seg := strings.TrimSpace(rest[:end]); seg != "" {
+			out = append(out, seg)
+		}
+		rest = rest[end:]
+	}
+	// Rewriting the builder reallocates and copies the whole buffer; skip it on
+	// the common per-token call where no boundary was confirmed.
+	if len(rest) != len(s) {
+		c.buf.Reset()
+		c.buf.WriteString(rest)
+	}
+	return out
+}
+
+// nextBoundary returns the byte offset just past the first emittable clause in
+// s, or ok=false when more input is needed (final=false) and no boundary is
+// confirmed yet.
+func (c *clauseChunker) nextBoundary(s string, final bool) (int, bool) {
+	if s == "" {
+		return 0, false
+	}
+
+	// 1) UAX #29 sentence boundary. When the first sentence is followed by more
+	//    text it is a confirmed complete sentence (handles Latin .!? with
+	//    abbreviation/decimal guards, and CJK 。！？ with no whitespace).
+	sentence, rest, _ := uniseg.FirstSentenceInString(s, -1)
+	if rest != "" {
+		// Optionally cut finer inside the sentence at a clause boundary.
+		if cut, ok := c.firstClauseCut(sentence); ok {
+			return cut, true
+		}
+		return len(sentence), true
+	}
+
+	// 2) Unterminated tail: look for a sub-sentence clause boundary (CJK
+	//    punctuation or a Thai/Lao space) confirmed by following content.
+	if cut, ok := c.firstClauseCut(s); ok {
+		return cut, true
+	}
+
+	// 3) Over-long punctuation-less run: force a typographically legal break so
+	//    we don't buffer unbounded (e.g. a long CJK run with no punctuation).
+	if !final && c.maxRunes > 0 && utf8.RuneCountInString(s) > c.maxRunes {
+		if cut, ok := lineBreakCut(s, c.maxRunes); ok {
+			return cut, true
+		}
+	}
+
+	// 4) End of input: emit whatever remains as the final clause.
+	if final {
+		return len(s), true
+	}
+	return 0, false
+}
+
+// firstClauseCut returns the byte offset just past the first sub-sentence clause
+// boundary in s — a CJK clause punctuation mark, or a space following a Thai/Lao
+// letter — provided the prefix is at least minRunes long and non-space content
+// follows. The boundary mark (and any trailing spaces) stay with the left clause.
+func (c *clauseChunker) firstClauseCut(s string) (int, bool) {
+	var prev rune
+	runes := 0
+	for i, r := range s {
+		boundary := isCJKClausePunct(r) || (unicode.IsSpace(r) && isThaiLao(prev))
+		if boundary && runes+1 >= c.minRunes {
+			end := i + utf8.RuneLen(r)
+			for end < len(s) {
+				nr, sz := utf8.DecodeRuneInString(s[end:])
+				if !unicode.IsSpace(nr) {
+					break
+				}
+				end += sz
+			}
+			if end < len(s) { // confirmed: real content follows the boundary
+				return end, true
+			}
+			// Boundary sits at the end of the buffer with nothing after it yet —
+			// wait for the next token to confirm it rather than emit early.
+			return 0, false
+		}
+		prev = r
+		runes++
+	}
+	return 0, false
+}
+
+// lineBreakCut walks UAX #14 line segments and returns the byte offset of the
+// last legal break opportunity at or before maxRunes. Returns ok=false when the
+// run has no internal break opportunity (e.g. a space-less Thai run), leaving it
+// buffered.
+func lineBreakCut(s string, maxRunes int) (int, bool) {
+	state := -1
+	rest := s
+	consumed := 0
+	runes := 0
+	for rest != "" {
+		seg, rem, _, st := uniseg.FirstLineSegmentInString(rest, state)
+		state = st
+		runes += utf8.RuneCountInString(seg)
+		consumed += len(seg)
+		rest = rem
+		if runes >= maxRunes {
+			if consumed < len(s) {
+				return consumed, true
+			}
+			return 0, false
+		}
+	}
+	return 0, false
+}
+
+// isCJKClausePunct reports whether r is a CJK clause-level separator worth a
+// soft TTS break. Sentence terminators (。！？) are intentionally excluded — UAX
+// #29 sentence segmentation already handles those.
+func isCJKClausePunct(r rune) bool {
+	switch r {
+	case '，', // ， fullwidth comma
+		'、', // 、 ideographic comma
+		'；', // ； fullwidth semicolon
+		'：', // ： fullwidth colon
+		'・', // ・ katakana middle dot
+		'･': // ・ halfwidth katakana middle dot
+		return true
+	}
+	return false
+}
+
+// isThaiLao reports whether r is a Thai or Lao letter. Those scripts have no
+// inter-word spaces; an ASCII space inside such a run marks a clause/sentence
+// boundary, which is the only no-dictionary segmentation signal available.
+func isThaiLao(r rune) bool {
+	return unicode.Is(unicode.Thai, r) || unicode.Is(unicode.Lao, r)
+}
--- a/core/http/endpoints/openai/realtime_chunker_test.go
+++ b/core/http/endpoints/openai/realtime_chunker_test.go
@@ -0,0 +1,103 @@
+package openai
+
+import (
+	"strings"
+	"unicode/utf8"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+// clauseChunker splits streamed LLM content into speakable clauses in a
+// script-aware way: UAX#29 sentences (Latin .!? and CJK 。！？), CJK clause
+// punctuation, and Thai/Lao spaces — never whitespace-splitting CJK.
+var _ = Describe("clauseChunker", func() {
+	Context("Latin sentences", func() {
+		It("emits a sentence only once following content confirms it is complete", func() {
+			c := newClauseChunker(12, 200)
+			Expect(c.push("Hello world. How are you?")).To(Equal([]string{"Hello world."}))
+			// The trailing sentence is held until flush (the next token might extend it).
+			Expect(c.flush()).To(Equal([]string{"How are you?"}))
+		})
+
+		It("assembles a sentence across many small tokens", func() {
+			c := newClauseChunker(12, 200)
+			var got []string
+			for _, tok := range []string{"Hello", " world.", " How", " are", " you?"} {
+				got = append(got, c.push(tok)...)
+			}
+			got = append(got, c.flush()...)
+			Expect(got).To(Equal([]string{"Hello world.", "How are you?"}))
+		})
+
+		It("does not split decimals or abbreviations (UAX#29 SB6)", func() {
+			c := newClauseChunker(12, 200)
+			got := c.push("Pi is 3.14 and e is 2.72. Done")
+			Expect(got).To(Equal([]string{"Pi is 3.14 and e is 2.72."}))
+			Expect(c.flush()).To(Equal([]string{"Done"}))
+		})
+	})
+
+	Context("CJK (no whitespace)", func() {
+		It("splits Chinese on the ideographic full stop", func() {
+			c := newClauseChunker(12, 200)
+			Expect(c.push("你好世界。今天天气很好。")).To(Equal([]string{"你好世界。"}))
+			Expect(c.flush()).To(Equal([]string{"今天天气很好。"}))
+		})
+
+		It("splits Japanese on the ideographic full stop", func() {
+			c := newClauseChunker(12, 200)
+			Expect(c.push("こんにちは。元気ですか。")).To(Equal([]string{"こんにちは。"}))
+			Expect(c.flush()).To(Equal([]string{"元気ですか。"}))
+		})
+
+		It("splits on CJK clause punctuation for lower latency", func() {
+			c := newClauseChunker(2, 200) // small min so short test clauses cut
+			Expect(c.push("你好，世界。再见")).To(Equal([]string{"你好，", "世界。"}))
+			Expect(c.flush()).To(Equal([]string{"再见"}))
+		})
+	})
+
+	Context("Thai (spaces mark clauses, not words)", func() {
+		It("splits a Thai run on the inter-clause space", func() {
+			c := newClauseChunker(2, 200)
+			Expect(c.push("สวัสดีครับ กินข้าวไหม")).To(Equal([]string{"สวัสดีครับ"}))
+			Expect(c.flush()).To(Equal([]string{"กินข้าวไหม"}))
+		})
+
+		It("never shatters a space-less Thai run into characters", func() {
+			c := newClauseChunker(2, 200)
+			Expect(c.push("สวัสดีครับ")).To(BeEmpty()) // held, no boundary
+			Expect(c.flush()).To(Equal([]string{"สวัสดีครับ"}))
+		})
+	})
+
+	Context("length cap (UAX#14 fallback)", func() {
+		It("force-breaks an over-long punctuation-less CJK run at legal points", func() {
+			c := newClauseChunker(4, 10) // maxRunes = 10
+			run := strings.Repeat("字", 25)
+			got := c.push(run)
+			got = append(got, c.flush()...)
+			total := 0
+			for _, seg := range got {
+				n := utf8.RuneCountInString(seg)
+				Expect(n).To(BeNumerically("<=", 10)) // never exceeds the cap
+				total += n
+			}
+			Expect(total).To(Equal(25))                       // nothing dropped
+			Expect(len(got)).To(BeNumerically(">=", 3))       // 10 + 10 + 5
+		})
+	})
+
+	Context("buffer lifecycle", func() {
+		It("flush clears the buffer so the chunker is reusable", func() {
+			c := newClauseChunker(12, 200)
+			// "First one." is confirmed by the following "Second", so push drains it;
+			// only the unterminated tail remains for flush.
+			Expect(c.push("First one. Second")).To(Equal([]string{"First one."}))
+			Expect(c.flush()).To(Equal([]string{"Second"}))
+			Expect(c.flush()).To(BeEmpty())
+			Expect(c.push("Again. More")).To(Equal([]string{"Again."}))
+		})
+	})
+})
--- a/core/http/endpoints/openai/realtime_doubles_test.go
+++ b/core/http/endpoints/openai/realtime_doubles_test.go
@@ -0,0 +1,138 @@
+package openai
+
+import (
+	"context"
+	"strings"
+
+	"github.com/mudler/LocalAI/core/backend"
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	"github.com/mudler/LocalAI/core/schema"
+	"github.com/mudler/LocalAI/pkg/grpc/proto"
+)
+
+// fakeTransport records the server events and audio sent to a realtime client
+// so streaming behaviour can be asserted without a real WebSocket/WebRTC peer.
+// It is not a *WebRTCTransport, so handler code takes the WebSocket path.
+type fakeTransport struct {
+	events []types.ServerEvent
+	audio  []fakeAudioChunk
+}
+
+type fakeAudioChunk struct {
+	pcm        []byte
+	sampleRate int
+}
+
+func (f *fakeTransport) SendEvent(e types.ServerEvent) error {
+	f.events = append(f.events, e)
+	return nil
+}
+
+func (f *fakeTransport) ReadEvent() ([]byte, error) { return nil, nil }
+
+func (f *fakeTransport) SendAudio(_ context.Context, pcm []byte, sampleRate int) error {
+	f.audio = append(f.audio, fakeAudioChunk{pcm: pcm, sampleRate: sampleRate})
+	return nil
+}
+
+func (f *fakeTransport) Close() error { return nil }
+
+// countEvents returns how many recorded events have the given type.
+func (f *fakeTransport) countEvents(et types.ServerEventType) int {
+	n := 0
+	for _, e := range f.events {
+		if e.ServerEventType() == et {
+			n++
+		}
+	}
+	return n
+}
+
+// transcriptDeltaText concatenates the Delta of every recorded transcript
+// delta event — i.e. the text streamed to the client as it is generated.
+func (f *fakeTransport) transcriptDeltaText() string {
+	var b strings.Builder
+	for _, e := range f.events {
+		if d, ok := e.(types.ResponseOutputAudioTranscriptDeltaEvent); ok {
+			b.WriteString(d.Delta)
+		}
+	}
+	return b.String()
+}
+
+// fakeModel is a configurable Model double. TTSStream replays ttsStreamChunks
+// and TranscribeStream replays transcribeDeltas, so the handler's streaming
+// paths can be driven deterministically.
+type fakeModel struct {
+	cfg *config.ModelConfig
+
+	ttsFile         string
+	ttsStreamChunks [][]byte
+	ttsStreamRate   int
+	ttsStreamErr    error
+
+	transcribeDeltas []string
+	transcribeFinal  *schema.TranscriptionResult
+
+	// Predict streaming: predictTokens are replayed through the token callback
+	// (simulating streamed LLM output); predictResp/predictErr are returned by
+	// the deferred predict function. predictChunkDeltas, when set, are delivered
+	// per-token via TokenUsage.ChatDeltas to exercise the autoparser path.
+	predictTokens      []string
+	predictChunkDeltas [][]*proto.ChatDelta
+	predictResp        backend.LLMResponse
+	predictErr         error
+}
+
+func (m *fakeModel) VAD(context.Context, *schema.VADRequest) (*schema.VADResponse, error) {
+	return nil, nil
+}
+
+func (m *fakeModel) Transcribe(context.Context, string, string, bool, bool, string) (*schema.TranscriptionResult, error) {
+	return m.transcribeFinal, nil
+}
+
+func (m *fakeModel) Predict(_ context.Context, _ schema.Messages, _, _, _ []string, cb func(string, backend.TokenUsage) bool, _ []types.ToolUnion, _ *types.ToolChoiceUnion, _, _ *int, _ map[string]float64) (func() (backend.LLMResponse, error), error) {
+	if m.predictErr != nil {
+		return nil, m.predictErr
+	}
+	return func() (backend.LLMResponse, error) {
+		for i, tok := range m.predictTokens {
+			if cb == nil {
+				continue
+			}
+			usage := backend.TokenUsage{}
+			if i < len(m.predictChunkDeltas) {
+				usage.ChatDeltas = m.predictChunkDeltas[i]
+			}
+			cb(tok, usage)
+		}
+		return m.predictResp, nil
+	}, nil
+}
+
+func (m *fakeModel) TTS(context.Context, string, string, string) (string, *proto.Result, error) {
+	return m.ttsFile, &proto.Result{Success: true}, nil
+}
+
+func (m *fakeModel) TTSStream(_ context.Context, _, _, _ string, onAudio func(pcm []byte, sampleRate int) error) error {
+	if m.ttsStreamErr != nil {
+		return m.ttsStreamErr
+	}
+	for _, c := range m.ttsStreamChunks {
+		if err := onAudio(c, m.ttsStreamRate); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (m *fakeModel) TranscribeStream(_ context.Context, _, _ string, _, _ bool, _ string, onDelta func(text string)) (*schema.TranscriptionResult, error) {
+	for _, d := range m.transcribeDeltas {
+		onDelta(d)
+	}
+	return m.transcribeFinal, nil
+}
+
+func (m *fakeModel) PredictConfig() *config.ModelConfig { return m.cfg }
--- a/core/http/endpoints/openai/realtime_model.go
+++ b/core/http/endpoints/openai/realtime_model.go
@@ -3,6 +3,7 @@ package openai
 import (
 	"context"
 	"crypto/rand"
+	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
@@ -87,6 +88,14 @@ func (m *transcriptOnlyModel) TTS(ctx context.Context, text, voice, language str
 	return "", nil, fmt.Errorf("TTS not supported in transcript-only mode")
 }

+func (m *transcriptOnlyModel) TTSStream(ctx context.Context, text, voice, language string, onAudio func(pcm []byte, sampleRate int) error) error {
+	return fmt.Errorf("TTS not supported in transcript-only mode")
+}
+
+func (m *transcriptOnlyModel) TranscribeStream(ctx context.Context, audio, language string, translate, diarize bool, prompt string, onDelta func(text string)) (*schema.TranscriptionResult, error) {
+	return transcribeStream(ctx, m.modelLoader, *m.TranscriptionConfig, m.appConfig, audio, language, translate, diarize, prompt, onDelta)
+}
+
 func (m *transcriptOnlyModel) PredictConfig() *config.ModelConfig {
 	return nil
 }
@@ -321,10 +330,75 @@ func (m *wrappedModel) TTS(ctx context.Context, text, voice, language string) (s
 	return backend.ModelTTS(ctx, text, voice, language, "", nil, m.modelLoader, m.appConfig, *m.TTSConfig)
 }

+func (m *wrappedModel) TTSStream(ctx context.Context, text, voice, language string, onAudio func(pcm []byte, sampleRate int) error) error {
+	return ttsStream(ctx, m.modelLoader, m.appConfig, *m.TTSConfig, text, voice, language, onAudio)
+}
+
+func (m *wrappedModel) TranscribeStream(ctx context.Context, audio, language string, translate, diarize bool, prompt string, onDelta func(text string)) (*schema.TranscriptionResult, error) {
+	return transcribeStream(ctx, m.modelLoader, *m.TranscriptionConfig, m.appConfig, audio, language, translate, diarize, prompt, onDelta)
+}
+
 func (m *wrappedModel) PredictConfig() *config.ModelConfig {
 	return m.LLMConfig
 }

+// wavStreamHeaderBytes is the size of the WAV header that backend.ModelTTSStream
+// emits as its first audio callback; the sample rate lives at byte offset 24.
+const wavStreamHeaderBytes = 44
+
+// ttsStream adapts backend.ModelTTSStream (which emits a WAV stream: a 44-byte
+// header carrying the sample rate, then raw PCM) to the realtime onAudio
+// callback, which wants raw PCM plus the sample rate. The header is buffered
+// until complete, the sample rate is read from it, and subsequent bytes are
+// forwarded as PCM.
+func ttsStream(ctx context.Context, ml *model.ModelLoader, appConfig *config.ApplicationConfig, ttsConfig config.ModelConfig, text, voice, language string, onAudio func(pcm []byte, sampleRate int) error) error {
+	var header []byte
+	headerDone := false
+	sampleRate := 0
+	return backend.ModelTTSStream(ctx, text, voice, language, "", nil, ml, appConfig, ttsConfig, func(b []byte) error {
+		if headerDone {
+			if len(b) == 0 {
+				return nil
+			}
+			return onAudio(b, sampleRate)
+		}
+		header = append(header, b...)
+		if len(header) < wavStreamHeaderBytes {
+			return nil
+		}
+		sampleRate = int(binary.LittleEndian.Uint32(header[24:28]))
+		headerDone = true
+		if len(header) > wavStreamHeaderBytes {
+			return onAudio(header[wavStreamHeaderBytes:], sampleRate)
+		}
+		return nil
+	})
+}
+
+// transcribeStream adapts backend.ModelTranscriptionStream to the realtime
+// onDelta callback, returning the final aggregated transcription result.
+func transcribeStream(ctx context.Context, ml *model.ModelLoader, transcriptionConfig config.ModelConfig, appConfig *config.ApplicationConfig, audio, language string, translate, diarize bool, prompt string, onDelta func(text string)) (*schema.TranscriptionResult, error) {
+	var final *schema.TranscriptionResult
+	err := backend.ModelTranscriptionStream(ctx, backend.TranscriptionRequest{
+		Audio:     audio,
+		Language:  language,
+		Translate: translate,
+		Diarize:   diarize,
+		Prompt:    prompt,
+	}, ml, transcriptionConfig, appConfig, func(chunk backend.TranscriptionStreamChunk) {
+		if chunk.Delta != "" {
+			onDelta(chunk.Delta)
+		}
+		if chunk.Final != nil {
+			final = chunk.Final
+		}
+	})
+	if err != nil {
+		return nil, err
+	}
+	return final, nil
+}
+
 func newTranscriptionOnlyModel(pipeline *config.Pipeline, cl *config.ModelConfigLoader, ml *model.ModelLoader, appConfig *config.ApplicationConfig) (Model, *config.ModelConfig, error) {
 	cfgVAD, err := cl.LoadModelConfigFileByName(pipeline.VAD, ml.ModelPath)
 	if err != nil {
@@ -454,8 +528,10 @@ func newModel(pipeline *config.Pipeline, cl *config.ModelConfigLoader, ml *model
 		return nil, fmt.Errorf("failed to validate config: %w", err)
 	}

-	// Let the pipeline set the LLM's reasoning effort (cfgLLM is a per-session copy).
+	// Let the pipeline set the LLM's reasoning effort and force thinking off
+	// (cfgLLM is a per-session copy). disable_thinking applies after the effort.
 	applyPipelineReasoning(cfgLLM, *pipeline)
+	applyPipelineThinking(cfgLLM, *pipeline)

 	cfgTTS, err := cl.LoadModelConfigFileByName(pipeline.TTS, ml.ModelPath)
 	if err != nil {
--- a/core/http/endpoints/openai/realtime_speech.go
+++ b/core/http/endpoints/openai/realtime_speech.go
@@ -0,0 +1,102 @@
+package openai
+
+import (
+	"context"
+	"encoding/base64"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	laudio "github.com/mudler/LocalAI/pkg/audio"
+	"github.com/mudler/LocalAI/pkg/sound"
+)
+
+// emitSpeech synthesizes text and sends the audio to the client. When the
+// pipeline opts into TTS streaming it forwards each PCM chunk as its own
+// response.output_audio.delta as soon as the backend produces it; otherwise it
+// synthesizes the whole utterance and sends it as a single delta.
+//
+// It deliberately does NOT emit transcript or audio-done events: the caller owns
+// those so a streamed reply can be split into several spoken segments that share
+// one response/item.
+//
+// It returns the PCM audio (at the session output rate) accumulated across all
+// chunks, which the caller base64-encodes onto the conversation item. For WebRTC
+// the audio goes over the RTP track instead, so the returned slice is empty.
+func emitSpeech(ctx context.Context, t Transport, session *Session, responseID, itemID, text string) ([]byte, error) {
+	if text == "" {
+		return nil, nil
+	}
+
+	_, isWebRTC := t.(*WebRTCTransport)
+
+	var wsAudio []byte // PCM at the session output rate, accumulated for the item record
+
+	// sendChunk hands one PCM buffer to the transport: WebRTC consumes the raw
+	// PCM directly (it resamples internally); WebSocket gets base64 PCM at the
+	// session output rate via a JSON delta event.
+	sendChunk := func(pcm []byte, sampleRate int) error {
+		if len(pcm) == 0 {
+			return nil
+		}
+		if err := t.SendAudio(ctx, pcm, sampleRate); err != nil {
+			return err
+		}
+		if isWebRTC {
+			return nil
+		}
+		wsPCM := pcm
+		if sampleRate != 0 && sampleRate != session.OutputSampleRate {
+			samples := sound.BytesToInt16sLE(pcm)
+			resampled := sound.ResampleInt16(samples, sampleRate, session.OutputSampleRate)
+			wsPCM = sound.Int16toBytesLE(resampled)
+		}
+		wsAudio = append(wsAudio, wsPCM...)
+		return t.SendEvent(types.ResponseOutputAudioDeltaEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			ItemID:          itemID,
+			OutputIndex:     0,
+			ContentIndex:    0,
+			Delta:           base64.StdEncoding.EncodeToString(wsPCM),
+		})
+	}
+
+	language := ""
+	if session.InputAudioTranscription != nil {
+		language = session.InputAudioTranscription.Language
+	}
+
+	if session.ModelConfig != nil && session.ModelConfig.Pipeline.StreamTTS() {
+		if err := session.ModelInterface.TTSStream(ctx, text, session.Voice, language, sendChunk); err != nil {
+			return nil, err
+		}
+		return wsAudio, nil
+	}
+
+	// Unary fallback: synthesize the whole utterance to a file, then emit once.
+	audioFilePath, res, err := session.ModelInterface.TTS(ctx, text, session.Voice, language)
+	if err != nil {
+		return nil, err
+	}
+	if res != nil && !res.Success {
+		return nil, fmt.Errorf("tts generation failed: %s", res.Message)
+	}
+	defer func() { _ = os.Remove(audioFilePath) }()
+
+	// filepath.Clean normalizes the backend-produced temp path before reading
+	// (also keeps gosec G304 quiet — the path is backend-controlled, not user input).
+	audioBytes, err := os.ReadFile(filepath.Clean(audioFilePath))
+	if err != nil {
+		return nil, fmt.Errorf("read tts audio: %w", err)
+	}
+	pcm, sampleRate := laudio.ParseWAV(audioBytes)
+	if sampleRate == 0 {
+		sampleRate = session.OutputSampleRate
+	}
+	if err := sendChunk(pcm, sampleRate); err != nil {
+		return nil, err
+	}
+	return wsAudio, nil
+}
--- a/core/http/endpoints/openai/realtime_speech_test.go
+++ b/core/http/endpoints/openai/realtime_speech_test.go
@@ -0,0 +1,70 @@
+package openai
+
+import (
+	"context"
+	"os"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	laudio "github.com/mudler/LocalAI/pkg/audio"
+)
+
+// emitSpeech synthesizes a piece of text and forwards the audio to the client,
+// streaming a delta per TTS chunk when the pipeline opts in, or sending the
+// whole utterance as one delta otherwise.
+var _ = Describe("emitSpeech", func() {
+	ttsOn := true
+
+	streamingSession := func(m Model) *Session {
+		return &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   m,
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{TTS: &ttsOn}},
+			},
+		}
+	}
+
+	It("streams one output_audio.delta per TTS chunk when streaming is enabled", func() {
+		m := &fakeModel{
+			ttsStreamChunks: [][]byte{{1, 2}, {3, 4}, {5, 6}},
+			ttsStreamRate:   24000,
+		}
+		t := &fakeTransport{}
+
+		audio, err := emitSpeech(context.Background(), t, streamingSession(m), "resp1", "item1", "Hello there.")
+
+		Expect(err).ToNot(HaveOccurred())
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioDelta)).To(Equal(3))
+		// The returned audio is all chunks concatenated (session output rate).
+		Expect(audio).To(Equal([]byte{1, 2, 3, 4, 5, 6}))
+	})
+
+	It("sends a single output_audio.delta in unary mode", func() {
+		// A minimal real WAV file for the unary TTS path to read + parse.
+		f, err := os.CreateTemp("", "emit-*.wav")
+		Expect(err).ToNot(HaveOccurred())
+		defer func() { _ = os.Remove(f.Name()) }()
+		pcm := make([]byte, 320) // 160 samples of silence
+		hdr := laudio.NewWAVHeader(uint32(len(pcm)))
+		Expect(hdr.Write(f)).To(Succeed())
+		_, err = f.Write(pcm)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(f.Close()).To(Succeed())
+
+		session := &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   &fakeModel{ttsFile: f.Name()},
+			ModelConfig:      &config.ModelConfig{}, // streaming off
+		}
+		t := &fakeTransport{}
+
+		_, err = emitSpeech(context.Background(), t, session, "resp1", "item1", "Hello there.")
+
+		Expect(err).ToNot(HaveOccurred())
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioDelta)).To(Equal(1))
+	})
+})
--- a/core/http/endpoints/openai/realtime_stream.go
+++ b/core/http/endpoints/openai/realtime_stream.go
@@ -0,0 +1,315 @@
+package openai
+
+import (
+	"context"
+	"encoding/base64"
+	"fmt"
+
+	"github.com/mudler/LocalAI/core/backend"
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	"github.com/mudler/LocalAI/core/schema"
+	"github.com/mudler/LocalAI/pkg/functions"
+	"github.com/mudler/LocalAI/pkg/reasoning"
+)
+
+// transcriptStreamer turns streamed LLM tokens into the assistant's spoken
+// transcript: it strips reasoning incrementally and sends one
+// response.output_audio_transcript.delta per content fragment. It does NOT
+// synthesize audio — the caller buffers the full message and synthesizes it
+// once (streaming the audio chunks when the TTS backend supports TTSStream),
+// which works uniformly for streaming and non-streaming TTS and for languages
+// without sentence or word boundaries.
+type transcriptStreamer struct {
+	ctx        context.Context
+	t          Transport
+	responseID string
+	itemID     string
+	extractor  *reasoning.ReasoningExtractor
+
+	// announce, if set, is invoked once just before the first transcript delta.
+	// It lets the caller create the assistant item lazily, so a content-less
+	// tool-call turn never emits a spurious empty assistant item.
+	announce  func()
+	announced bool
+}
+
+func newTranscriptStreamer(ctx context.Context, t Transport, responseID, itemID, thinkingStartToken string, reasoningCfg reasoning.Config) *transcriptStreamer {
+	return &transcriptStreamer{
+		ctx:        ctx,
+		t:          t,
+		responseID: responseID,
+		itemID:     itemID,
+		extractor:  reasoning.NewReasoningExtractor(thinkingStartToken, spokenReasoningConfig(reasoningCfg)),
+	}
+}
+
+// onToken handles one streamed unit of model output, sending a transcript delta
+// for the new content (reasoning stripped) and returning that content delta so
+// the caller can also feed it to the clause chunker. For plain-content models
+// the unit is the raw text token; for autoparser tool turns the backend clears
+// the text and delivers content via ChatDeltas, so the caller passes that
+// content here. Returns "" when the token produced no new spoken content.
+func (s *transcriptStreamer) onToken(token string) string {
+	_, content := s.extractor.ProcessToken(token)
+	if content == "" {
+		return ""
+	}
+	if !s.announced {
+		s.announced = true
+		if s.announce != nil {
+			s.announce()
+		}
+	}
+	_ = s.t.SendEvent(types.ResponseOutputAudioTranscriptDeltaEvent{
+		ServerEventBase: types.ServerEventBase{},
+		ResponseID:      s.responseID,
+		ItemID:          s.itemID,
+		OutputIndex:     0,
+		ContentIndex:    0,
+		Delta:           content,
+	})
+	return content
+}
+
+// content returns the full transcript so far with reasoning stripped.
+func (s *transcriptStreamer) content() string {
+	return s.extractor.CleanedContent()
+}
+
+// streamLLMResponse drives a streamed realtime reply. It streams the assistant
+// transcript as the LLM generates, then synthesizes the whole buffered message
+// once (streaming the audio chunks when the TTS backend supports it, otherwise a
+// single unary delta). Tool calls parsed from the autoparser ChatDeltas are
+// emitted after the spoken content. The assistant content item is created lazily
+// on the first content delta, so a content-less tool-call turn emits only the
+// tool calls. It returns true when it has fully handled the response so the
+// caller can return; callers must only invoke it for an audio modality, and with
+// tools only when the model uses its tokenizer template (see triggerResponseAtTurn).
+func streamLLMResponse(ctx context.Context, session *Session, conv *Conversation, t Transport, responseID string, history schema.Messages, images []string, llmCfg *config.ModelConfig, tools []types.ToolUnion, toolChoice *types.ToolChoiceUnion, toolTurn int) bool {
+	itemID := generateItemID()
+	item := types.MessageItemUnion{
+		Assistant: &types.MessageItemAssistant{
+			ID:      itemID,
+			Status:  types.ItemStatusInProgress,
+			Content: []types.MessageContentOutput{{Type: types.MessageContentTypeOutputAudio}},
+		},
+	}
+
+	// announce creates the assistant content item lazily, just before the first
+	// transcript delta — a tool-only turn never produces content, so it stays out
+	// of the conversation and the client sees only the tool calls.
+	announced := false
+	announce := func() {
+		announced = true
+		conv.Lock.Lock()
+		conv.Items = append(conv.Items, &item)
+		conv.Lock.Unlock()
+		sendEvent(t, types.ResponseOutputItemAddedEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			OutputIndex:     0,
+			Item:            item,
+		})
+		sendEvent(t, types.ResponseContentPartAddedEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			ItemID:          itemID,
+			OutputIndex:     0,
+			ContentIndex:    0,
+			Part:            item.Assistant.Content[0],
+		})
+	}
+
+	cancel := func() {
+		if announced {
+			conv.Lock.Lock()
+			for i := len(conv.Items) - 1; i >= 0; i-- {
+				if conv.Items[i].Assistant != nil && conv.Items[i].Assistant.ID == itemID {
+					conv.Items = append(conv.Items[:i], conv.Items[i+1:]...)
+					break
+				}
+			}
+			conv.Lock.Unlock()
+		}
+		sendEvent(t, types.ResponseDoneEvent{
+			ServerEventBase: types.ServerEventBase{},
+			Response:        types.Response{ID: responseID, Object: "realtime.response", Status: types.ResponseStatusCancelled},
+		})
+	}
+
+	var template string
+	if llmCfg.TemplateConfig.UseTokenizerTemplate {
+		template = llmCfg.GetModelTemplate()
+	} else {
+		template = llmCfg.TemplateConfig.Chat
+	}
+	thinkingStartToken := reasoning.DetectThinkingStartToken(template, &llmCfg.ReasoningConfig)
+
+	// The autoparser (tokenizer-template path) already delivers reasoning-free
+	// content. Prefilling the thinking start token here would re-tag that clean
+	// content as an unclosed reasoning block, leaving CleanedContent() empty —
+	// no spoken reply, no TTS. Disable the prefill; closed tag pairs are still
+	// stripped (PEG-fallback case, #9985).
+	reasoningCfg := llmCfg.ReasoningConfig
+	if llmCfg.TemplateConfig.UseTokenizerTemplate {
+		disablePrefill := true
+		reasoningCfg.DisableReasoningTagPrefill = &disablePrefill
+	}
+
+	streamer := newTranscriptStreamer(ctx, t, responseID, itemID, thinkingStartToken, reasoningCfg)
+	streamer.announce = announce
+
+	// Clause chunking (opt-in): synthesize each clause as soon as it completes
+	// instead of buffering the whole reply. streamedAudio accumulates the PCM
+	// across clauses for the conversation item record; ttsErr captures the first
+	// synthesis failure so the token callback can stop the prediction. emitSpeech
+	// runs synchronously here — the LLM keeps generating into the gRPC stream
+	// while a clause is synthesized, so audio still starts mid-generation.
+	var chunker *clauseChunker
+	if session.ModelConfig != nil && session.ModelConfig.Pipeline.ChunkClauses() {
+		chunker = newClauseChunker(defaultClauseMinRunes, defaultClauseMaxRunes)
+	}
+	var streamedAudio []byte
+	var ttsErr error
+	speakClause := func(clause string) error {
+		a, err := emitSpeech(ctx, t, session, responseID, itemID, clause)
+		if err != nil {
+			return err
+		}
+		streamedAudio = append(streamedAudio, a...)
+		return nil
+	}
+
+	// fail reports a mid-stream failure. A cancelled context means the client
+	// interrupted (barge-in), so roll the turn back instead of erroring.
+	fail := func(code, msg string, err error) bool {
+		if ctx.Err() != nil {
+			cancel()
+		} else {
+			sendError(t, code, fmt.Sprintf("%s: %v", msg, err), "", itemID)
+		}
+		return true
+	}
+
+	cb := func(token string, usage backend.TokenUsage) bool {
+		if ctx.Err() != nil {
+			return false
+		}
+		// Plain-content models stream text via the token; autoparser tool turns
+		// clear the text and deliver content via ChatDeltas, so prefer the latter
+		// when present. Either way only content reaches the transcript — tool-call
+		// deltas are parsed from the final response below.
+		text := token
+		if len(usage.ChatDeltas) > 0 {
+			text = functions.ContentFromChatDeltas(usage.ChatDeltas)
+		}
+		delta := streamer.onToken(text)
+		if chunker != nil && delta != "" {
+			for _, clause := range chunker.push(delta) {
+				if ttsErr = speakClause(clause); ttsErr != nil {
+					return false // stop the prediction; reported after predFunc returns
+				}
+			}
+		}
+		return true
+	}
+
+	predFunc, err := session.ModelInterface.Predict(ctx, history, images, nil, nil, cb, tools, toolChoice, nil, nil, nil)
+	if err != nil {
+		sendError(t, "inference_failed", fmt.Sprintf("backend error: %v", err), "", itemID)
+		return true
+	}
+	pred, err := predFunc()
+	// A clause synthesis failed mid-stream (the callback stopped the prediction);
+	// report it as a TTS error rather than a prediction error.
+	if ttsErr != nil {
+		return fail("tts_error", "TTS generation failed", ttsErr)
+	}
+	if err != nil {
+		return fail("prediction_failed", "backend error", err)
+	}
+	if ctx.Err() != nil {
+		cancel()
+		return true
+	}
+
+	content := streamer.content()
+	toolCalls := functions.ToolCallsFromChatDeltas(pred.ChatDeltas)
+
+	// Finalize the spoken content item only when the turn produced content. A
+	// tool-only turn skips this entirely (no empty assistant item).
+	if content != "" {
+		if !announced {
+			announce()
+		}
+
+		// Synthesize the audio. With clause chunking the completed clauses were
+		// already spoken inside the token callback; flush the trailing clause(s)
+		// the segmenter was still holding. Otherwise buffer the whole message and
+		// synthesize it once. emitSpeech streams the audio chunks when the TTS
+		// backend supports TTSStream, otherwise it sends a single unary delta.
+		var audio []byte
+		if chunker != nil {
+			for _, clause := range chunker.flush() {
+				if ttsErr = speakClause(clause); ttsErr != nil {
+					break
+				}
+			}
+			audio = streamedAudio
+		} else {
+			audio, ttsErr = emitSpeech(ctx, t, session, responseID, itemID, content)
+		}
+		if ttsErr != nil {
+			return fail("tts_error", "TTS generation failed", ttsErr)
+		}
+
+		_, isWebRTC := t.(*WebRTCTransport)
+
+		sendEvent(t, types.ResponseOutputAudioTranscriptDoneEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			ItemID:          itemID,
+			OutputIndex:     0,
+			ContentIndex:    0,
+			Transcript:      content,
+		})
+		if !isWebRTC {
+			sendEvent(t, types.ResponseOutputAudioDoneEvent{
+				ServerEventBase: types.ServerEventBase{},
+				ResponseID:      responseID,
+				ItemID:          itemID,
+				OutputIndex:     0,
+				ContentIndex:    0,
+			})
+		}
+
+		conv.Lock.Lock()
+		item.Assistant.Status = types.ItemStatusCompleted
+		item.Assistant.Content[0].Transcript = content
+		if !isWebRTC {
+			item.Assistant.Content[0].Audio = base64.StdEncoding.EncodeToString(audio)
+		}
+		conv.Lock.Unlock()
+
+		sendEvent(t, types.ResponseContentPartDoneEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			ItemID:          itemID,
+			OutputIndex:     0,
+			ContentIndex:    0,
+			Part:            item.Assistant.Content[0],
+		})
+		sendEvent(t, types.ResponseOutputItemDoneEvent{
+			ServerEventBase: types.ServerEventBase{},
+			ResponseID:      responseID,
+			OutputIndex:     0,
+			Item:            item,
+		})
+	}
+
+	// Emit any tool calls, the terminal response.done, and (for server-side
+	// assistant tools) the follow-up turn — shared with the buffered path.
+	emitToolCallItems(ctx, session, conv, t, responseID, toolCalls, content != "", toolTurn)
+	return true
+}
--- a/core/http/endpoints/openai/realtime_stream_test.go
+++ b/core/http/endpoints/openai/realtime_stream_test.go
@@ -0,0 +1,213 @@
+package openai
+
+import (
+	"context"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/mudler/LocalAI/core/backend"
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	"github.com/mudler/LocalAI/pkg/grpc/proto"
+	"github.com/mudler/LocalAI/pkg/reasoning"
+)
+
+// transcriptStreamer turns streamed LLM tokens into incremental transcript
+// deltas, stripping reasoning. Audio is synthesized once from the full message
+// by the caller, so there is no per-sentence segmentation.
+var _ = Describe("transcriptStreamer", func() {
+	It("emits one transcript delta per content token", func() {
+		t := &fakeTransport{}
+		s := newTranscriptStreamer(context.Background(), t, "resp1", "item1", "", reasoning.Config{})
+
+		for _, tok := range []string{"Hello", " world.", " Bye"} {
+			s.onToken(tok)
+		}
+
+		Expect(s.content()).To(Equal("Hello world. Bye"))
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioTranscriptDelta)).To(Equal(3))
+		Expect(t.transcriptDeltaText()).To(Equal("Hello world. Bye"))
+	})
+
+	It("strips leaked reasoning even when reasoning is disabled (disable_thinking safety net)", func() {
+		// disable_thinking maps to DisableReasoning=true (enable_thinking=false to
+		// the backend). If the model emits thinking anyway, the transcript must
+		// still not leak it: stripping always runs for spoken output.
+		disable := true
+		t := &fakeTransport{}
+		s := newTranscriptStreamer(context.Background(), t, "resp1", "item1", "",
+			reasoning.Config{DisableReasoning: &disable})
+
+		s.onToken("<think>secret plan</think>")
+		s.onToken("The answer is 42.")
+
+		Expect(s.content()).To(Equal("The answer is 42."))
+		Expect(s.content()).ToNot(ContainSubstring("secret plan"))
+		Expect(t.transcriptDeltaText()).ToNot(ContainSubstring("secret plan"))
+	})
+
+	It("does not swallow autoparser content when the template has a thinking start token (tokenizer-template path)", func() {
+		// Regression: with tag prefill on, the detected <think> token is
+		// prepended to the autoparser's already-clean content, swallowing the
+		// whole reply (empty transcript → no TTS). streamLLMResponse disables
+		// the prefill for the tokenizer-template path.
+		disablePrefill := true
+		t := &fakeTransport{}
+		s := newTranscriptStreamer(context.Background(), t, "resp1", "item1", "<think>",
+			reasoning.Config{DisableReasoningTagPrefill: &disablePrefill})
+
+		s.onToken("Hello")
+		s.onToken(" there.")
+
+		Expect(s.content()).To(Equal("Hello there."))
+		Expect(t.transcriptDeltaText()).To(Equal("Hello there."))
+	})
+
+	It("still strips embedded closed reasoning tags with prefill disabled (PEG-fallback safety, #9985)", func() {
+		// Disabling prefill must not stop stripping closed <think>…</think>
+		// pairs the PEG fallback can leave in autoparser content.
+		disablePrefill := true
+		t := &fakeTransport{}
+		s := newTranscriptStreamer(context.Background(), t, "resp1", "item1", "<think>",
+			reasoning.Config{DisableReasoningTagPrefill: &disablePrefill})
+
+		s.onToken("<think>secret</think>")
+		s.onToken("The answer is 42.")
+
+		Expect(s.content()).To(Equal("The answer is 42."))
+		Expect(t.transcriptDeltaText()).ToNot(ContainSubstring("secret"))
+	})
+})
+
+// streamLLMResponse drives a full streamed realtime turn: live transcript
+// deltas while the LLM generates, then the whole message is synthesized once.
+var _ = Describe("streamLLMResponse", func() {
+	It("streams transcript deltas then synthesizes the whole message once", func() {
+		on := true
+		m := &fakeModel{
+			predictTokens:   []string{"Hello", " world.", " How are you?"},
+			predictResp:     backend.LLMResponse{Response: "Hello world. How are you?"},
+			ttsStreamChunks: [][]byte{{9}},
+			ttsStreamRate:   24000,
+		}
+		session := &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   m,
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{LLM: &on, TTS: &on}},
+			},
+		}
+		conv := &Conversation{}
+		t := &fakeTransport{}
+		llmCfg := &config.ModelConfig{}
+
+		handled := streamLLMResponse(context.Background(), session, conv, t, "resp1", nil, nil, llmCfg, nil, nil, 0)
+
+		Expect(handled).To(BeTrue())
+		// One live transcript delta per streamed token.
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioTranscriptDelta)).To(Equal(3))
+		// The whole message is synthesized ONCE (not per sentence): a single
+		// emitSpeech replays the one TTS stream chunk.
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioDelta)).To(Equal(1))
+		Expect(t.transcriptDeltaText()).To(Equal("Hello world. How are you?"))
+	})
+
+	It("synthesizes each clause as it completes when clause chunking is enabled", func() {
+		on := true
+		m := &fakeModel{
+			predictTokens:   []string{"Hello world.", " How are you?"},
+			predictResp:     backend.LLMResponse{Response: "Hello world. How are you?"},
+			ttsStreamChunks: [][]byte{{9}},
+			ttsStreamRate:   24000,
+		}
+		session := &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   m,
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{LLM: &on, TTS: &on, ClauseChunking: &on}},
+			},
+		}
+		conv := &Conversation{}
+		t := &fakeTransport{}
+		llmCfg := &config.ModelConfig{}
+
+		handled := streamLLMResponse(context.Background(), session, conv, t, "resp1", nil, nil, llmCfg, nil, nil, 0)
+
+		Expect(handled).To(BeTrue())
+		// Two clauses ("Hello world." mid-stream, "How are you?" on flush) → two
+		// emitSpeech calls → two audio deltas, vs one for whole-message buffering.
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioDelta)).To(Equal(2))
+		// The full transcript still streams verbatim.
+		Expect(t.transcriptDeltaText()).To(Equal("Hello world. How are you?"))
+		// Exactly one terminal response.done.
+		Expect(t.countEvents(types.ServerEventTypeResponseDone)).To(Equal(1))
+	})
+
+	It("streams content deltas and emits tool-call items (autoparser tool turn)", func() {
+		on := true
+		// Autoparser path: reply.Message is empty; content + tool calls arrive via
+		// ChatDeltas. Chunk 1 carries content, chunk 2 carries the tool call.
+		contentDelta := []*proto.ChatDelta{{Content: "Let me check."}}
+		toolDelta := []*proto.ChatDelta{{ToolCalls: []*proto.ToolCallDelta{{Index: 0, Name: "get_weather", Arguments: `{"city":"Paris"}`}}}}
+		m := &fakeModel{
+			predictTokens:      []string{"", ""},
+			predictChunkDeltas: [][]*proto.ChatDelta{contentDelta, toolDelta},
+			predictResp:        backend.LLMResponse{ChatDeltas: append(append([]*proto.ChatDelta{}, contentDelta...), toolDelta...)},
+			ttsStreamChunks:    [][]byte{{9}},
+			ttsStreamRate:      24000,
+		}
+		session := &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   m,
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{LLM: &on, TTS: &on}},
+			},
+		}
+		conv := &Conversation{}
+		t := &fakeTransport{}
+		llmCfg := &config.ModelConfig{}
+		llmCfg.TemplateConfig.UseTokenizerTemplate = true
+
+		handled := streamLLMResponse(context.Background(), session, conv, t, "resp1", nil, nil, llmCfg, nil, nil, 0)
+
+		Expect(handled).To(BeTrue())
+		// The spoken content was streamed live.
+		Expect(t.transcriptDeltaText()).To(Equal("Let me check."))
+		// The tool call is emitted as a function_call item.
+		Expect(t.countEvents(types.ServerEventTypeResponseFunctionCallArgumentsDone)).To(Equal(1))
+		// Exactly one terminal response.done.
+		Expect(t.countEvents(types.ServerEventTypeResponseDone)).To(Equal(1))
+	})
+
+	It("emits only tool-call items for a content-less tool turn (no empty assistant item)", func() {
+		on := true
+		toolDelta := []*proto.ChatDelta{{ToolCalls: []*proto.ToolCallDelta{{Index: 0, Name: "get_weather", Arguments: `{"city":"Rome"}`}}}}
+		m := &fakeModel{
+			predictTokens:      []string{""},
+			predictChunkDeltas: [][]*proto.ChatDelta{toolDelta},
+			predictResp:        backend.LLMResponse{ChatDeltas: toolDelta},
+		}
+		session := &Session{
+			OutputSampleRate: 24000,
+			ModelInterface:   m,
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{LLM: &on, TTS: &on}},
+			},
+		}
+		conv := &Conversation{}
+		t := &fakeTransport{}
+		llmCfg := &config.ModelConfig{}
+		llmCfg.TemplateConfig.UseTokenizerTemplate = true
+
+		handled := streamLLMResponse(context.Background(), session, conv, t, "resp1", nil, nil, llmCfg, nil, nil, 0)
+
+		Expect(handled).To(BeTrue())
+		// No content → no transcript deltas and no spurious assistant content item.
+		Expect(t.transcriptDeltaText()).To(Equal(""))
+		Expect(t.countEvents(types.ServerEventTypeResponseOutputAudioTranscriptDelta)).To(Equal(0))
+		// The tool call is still emitted.
+		Expect(t.countEvents(types.ServerEventTypeResponseFunctionCallArgumentsDone)).To(Equal(1))
+		Expect(t.countEvents(types.ServerEventTypeResponseDone)).To(Equal(1))
+	})
+})
--- a/core/http/endpoints/openai/realtime_thinking.go
+++ b/core/http/endpoints/openai/realtime_thinking.go
@@ -0,0 +1,33 @@
+package openai
+
+import (
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/pkg/reasoning"
+)
+
+// applyPipelineThinking forces the LLM's reasoning/thinking off when the realtime
+// pipeline sets disable_thinking, mapping to the enable_thinking=false backend
+// metadata via ReasoningConfig.DisableReasoning. The LLM config passed in is the
+// per-session copy returned by the config loader, so this does not affect other
+// users of the same model. When the pipeline does not set disable_thinking the
+// LLM config is left untouched.
+func applyPipelineThinking(llm *config.ModelConfig, pipeline config.Pipeline) {
+	if llm == nil || !pipeline.ThinkingDisabled() {
+		return
+	}
+	disable := true
+	llm.ReasoningConfig.DisableReasoning = &disable
+}
+
+// spokenReasoningConfig adapts a model's reasoning config for stripping reasoning
+// OUT of realtime spoken output. ReasoningConfig.DisableReasoning is overloaded:
+// the backend reads it as the "enable_thinking=false" hint (which pipeline
+// disable_thinking sets via applyPipelineThinking), but the reasoning extractor
+// reads it as "skip stripping, assume there is no reasoning". Honouring the latter
+// when extracting for speech would leak raw <think>…</think> whenever the model
+// ignores the suppression hint. Spoken output must never contain reasoning, so we
+// always strip: clear DisableReasoning while keeping custom tokens/tag pairs.
+func spokenReasoningConfig(cfg reasoning.Config) reasoning.Config {
+	cfg.DisableReasoning = nil
+	return cfg
+}
--- a/core/http/endpoints/openai/realtime_thinking_test.go
+++ b/core/http/endpoints/openai/realtime_thinking_test.go
@@ -0,0 +1,50 @@
+package openai
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/pkg/reasoning"
+)
+
+// applyPipelineThinking lets a realtime pipeline force the LLM's thinking off
+// (enable_thinking=false metadata) without editing the LLM model config.
+var _ = Describe("applyPipelineThinking", func() {
+	It("disables reasoning on the LLM config when the pipeline disables thinking", func() {
+		disable := true
+		llm := &config.ModelConfig{}
+		applyPipelineThinking(llm, config.Pipeline{DisableThinking: &disable})
+		Expect(llm.ReasoningConfig.DisableReasoning).ToNot(BeNil())
+		Expect(*llm.ReasoningConfig.DisableReasoning).To(BeTrue())
+	})
+
+	It("leaves the LLM config untouched when the pipeline does not set disable_thinking", func() {
+		llm := &config.ModelConfig{}
+		applyPipelineThinking(llm, config.Pipeline{})
+		Expect(llm.ReasoningConfig.DisableReasoning).To(BeNil())
+	})
+})
+
+// spokenReasoningConfig clears DisableReasoning so realtime spoken output always
+// strips reasoning, even though disable_thinking sets DisableReasoning=true on the
+// LLM config (which the backend reads as enable_thinking=false).
+var _ = Describe("spokenReasoningConfig", func() {
+	It("clears DisableReasoning so the extractor still strips leaked reasoning", func() {
+		disable := true
+		out := spokenReasoningConfig(reasoning.Config{DisableReasoning: &disable})
+		Expect(out.DisableReasoning).To(BeNil())
+	})
+
+	It("preserves the other reasoning settings", func() {
+		disable := true
+		out := spokenReasoningConfig(reasoning.Config{
+			DisableReasoning:    &disable,
+			ThinkingStartTokens: []string{"<reason>"},
+			TagPairs:            []reasoning.TagPair{{Start: "<reason>", End: "</reason>"}},
+		})
+		Expect(out.ThinkingStartTokens).To(Equal([]string{"<reason>"}))
+		Expect(out.TagPairs).To(HaveLen(1))
+		Expect(out.TagPairs[0].Start).To(Equal("<reason>"))
+	})
+})
--- a/core/http/endpoints/openai/realtime_transcription.go
+++ b/core/http/endpoints/openai/realtime_transcription.go
@@ -0,0 +1,63 @@
+package openai
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+)
+
+// emitTranscription transcribes a committed utterance and emits the transcription
+// events for it, returning the final transcript text. With
+// pipeline.streaming.transcription enabled it streams each transcript fragment as
+// a conversation.item.input_audio_transcription.delta as the backend produces it,
+// then a completed event; otherwise it transcribes the whole utterance and emits
+// a single completed event. delta and completed events share itemID.
+func emitTranscription(ctx context.Context, t Transport, session *Session, itemID, audioPath string) (string, error) {
+	cfg := session.InputAudioTranscription
+
+	if session.ModelConfig != nil && session.ModelConfig.Pipeline.StreamTranscription() {
+		final, err := session.ModelInterface.TranscribeStream(ctx, audioPath, cfg.Language, false, false, cfg.Prompt, func(delta string) {
+			_ = t.SendEvent(types.ConversationItemInputAudioTranscriptionDeltaEvent{
+				ServerEventBase: types.ServerEventBase{EventID: "event_TODO"},
+				ItemID:          itemID,
+				ContentIndex:    0,
+				Delta:           delta,
+			})
+		})
+		if err != nil {
+			return "", err
+		}
+		transcript := ""
+		if final != nil {
+			transcript = final.Text
+		}
+		if err := t.SendEvent(types.ConversationItemInputAudioTranscriptionCompletedEvent{
+			ServerEventBase: types.ServerEventBase{EventID: "event_TODO"},
+			ItemID:          itemID,
+			ContentIndex:    0,
+			Transcript:      transcript,
+		}); err != nil {
+			return "", err
+		}
+		return transcript, nil
+	}
+
+	// Unary fallback: transcribe the whole utterance, emit one completed event.
+	tr, err := session.ModelInterface.Transcribe(ctx, audioPath, cfg.Language, false, false, cfg.Prompt)
+	if err != nil {
+		return "", err
+	}
+	if tr == nil {
+		return "", fmt.Errorf("transcribe result is nil")
+	}
+	if err := t.SendEvent(types.ConversationItemInputAudioTranscriptionCompletedEvent{
+		ServerEventBase: types.ServerEventBase{EventID: "event_TODO"},
+		ItemID:          itemID,
+		ContentIndex:    0,
+		Transcript:      tr.Text,
+	}); err != nil {
+		return "", err
+	}
+	return tr.Text, nil
+}
--- a/core/http/endpoints/openai/realtime_transcription_test.go
+++ b/core/http/endpoints/openai/realtime_transcription_test.go
@@ -0,0 +1,54 @@
+package openai
+
+import (
+	"context"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/mudler/LocalAI/core/config"
+	"github.com/mudler/LocalAI/core/http/endpoints/openai/types"
+	"github.com/mudler/LocalAI/core/schema"
+)
+
+// emitTranscription transcribes a committed utterance, streaming transcript text
+// deltas when the pipeline opts in, and returns the final transcript text.
+var _ = Describe("emitTranscription", func() {
+	It("streams transcription deltas then a completed event when streaming is enabled", func() {
+		on := true
+		session := &Session{
+			InputAudioTranscription: &types.AudioTranscription{},
+			ModelConfig: &config.ModelConfig{
+				Pipeline: config.Pipeline{Streaming: config.PipelineStreaming{Transcription: &on}},
+			},
+			ModelInterface: &fakeModel{
+				transcribeDeltas: []string{"Hel", "lo", " world"},
+				transcribeFinal:  &schema.TranscriptionResult{Text: "Hello world"},
+			},
+		}
+		t := &fakeTransport{}
+
+		transcript, err := emitTranscription(context.Background(), t, session, "item1", "/tmp/x.wav")
+
+		Expect(err).ToNot(HaveOccurred())
+		Expect(transcript).To(Equal("Hello world"))
+		Expect(t.countEvents(types.ServerEventTypeConversationItemInputAudioTranscriptionDelta)).To(Equal(3))
+		Expect(t.countEvents(types.ServerEventTypeConversationItemInputAudioTranscriptionCompleted)).To(Equal(1))
+	})
+
+	It("emits a single completed event with no deltas in unary mode", func() {
+		session := &Session{
+			InputAudioTranscription: &types.AudioTranscription{},
+			ModelConfig:             &config.ModelConfig{}, // streaming off
+			ModelInterface:          &fakeModel{transcribeFinal: &schema.TranscriptionResult{Text: "Hi"}},
+		}
+		t := &fakeTransport{}
+
+		transcript, err := emitTranscription(context.Background(), t, session, "item1", "/tmp/x.wav")
+
+		Expect(err).ToNot(HaveOccurred())
+		Expect(transcript).To(Equal("Hi"))
+		Expect(t.countEvents(types.ServerEventTypeConversationItemInputAudioTranscriptionDelta)).To(Equal(0))
+		Expect(t.countEvents(types.ServerEventTypeConversationItemInputAudioTranscriptionCompleted)).To(Equal(1))
+	})
+})
--- a/core/http/react-ui/src/pages/Talk.jsx
+++ b/core/http/react-ui/src/pages/Talk.jsx
@@ -17,6 +17,24 @@ const STATUS_STYLES = {
  error:        { icon: 'fa-solid fa-circle', color: 'var(--color-error)', bg: 'var(--color-error-light)' },
 }

+// upsertAssistant merges a streamed transcript fragment into the assistant entry
+// identified by the server's item_id, or appends a new entry if none exists yet.
+// Keying by item_id (not a mutable index tracked across handler/updater
+// boundaries) makes streamed deltas idempotent and order-independent, so React's
+// batching of non-React data-channel events cannot produce a duplicate bubble.
+// mode 'append' adds to the running text; 'replace' sets the final transcript.
+function upsertAssistant(prev, itemId, text, mode) {
+  // Only assistant entries carry an id, and the streaming entry is almost
+  // always the newest — search from the tail so per-delta cost stays constant.
+  const i = prev.findLastIndex(e => e.id === itemId)
+  if (i === -1) {
+    return [...prev, { role: 'assistant', id: itemId, text }]
+  }
+  const next = [...prev]
+  next[i] = { ...next[i], text: mode === 'append' ? next[i].text + text : text }
+  return next
+}
+
 export default function Talk() {
  const { addToast } = useOutletContext()
  const navigate = useNavigate()
@@ -34,7 +52,10 @@ export default function Talk() {

  // Transcript
  const [transcript, setTranscript] = useState([])
-  const streamingRef = useRef(null) // tracks the index of the in-progress assistant message
+  // item_id of the assistant message currently streaming — used only to remove
+  // its partial bubble when a response is cancelled (barge-in). The transcript
+  // itself is keyed by item_id via upsertAssistant, not by this ref.
+  const inProgressIdRef = useRef(null)

  // Session settings
  const [instructions, setInstructions] = useState(
@@ -227,39 +248,21 @@ export default function Talk() {
        break
      case 'conversation.item.input_audio_transcription.completed':
        if (event.transcript) {
-          streamingRef.current = null
          setTranscript(prev => [...prev, { role: 'user', text: event.transcript }])
        }
        updateStatus('thinking', 'Generating response...')
        break
      case 'response.output_audio_transcript.delta':
        if (event.delta) {
-          setTranscript(prev => {
-            if (streamingRef.current !== null) {
-              const updated = [...prev]
-              updated[streamingRef.current] = {
-                ...updated[streamingRef.current],
-                text: updated[streamingRef.current].text + event.delta,
-              }
-              return updated
-            }
-            streamingRef.current = prev.length
-            return [...prev, { role: 'assistant', text: event.delta }]
-          })
+          inProgressIdRef.current = event.item_id
+          setTranscript(prev => upsertAssistant(prev, event.item_id, event.delta, 'append'))
        }
        break
      case 'response.output_audio_transcript.done':
        if (event.transcript) {
-          setTranscript(prev => {
-            if (streamingRef.current !== null) {
-              const updated = [...prev]
-              updated[streamingRef.current] = { ...updated[streamingRef.current], text: event.transcript }
-              return updated
-            }
-            return [...prev, { role: 'assistant', text: event.transcript }]
-          })
+          setTranscript(prev => upsertAssistant(prev, event.item_id, event.transcript, 'replace'))
        }
-        streamingRef.current = null
+        inProgressIdRef.current = null
        break
      case 'response.output_audio.delta':
        updateStatus('speaking', 'Speaking...')
@@ -281,7 +284,7 @@ export default function Talk() {
          // Pretty-print JSON for readability; fall back to raw string.
          try { preview = JSON.stringify(JSON.parse(preview), null, 2) } catch (_) { /* keep raw */ }
          setTranscript(prev => [...prev, { role: 'tool_result', text: preview }])
-          streamingRef.current = null  // tool result ends the current assistant text run
+          inProgressIdRef.current = null // tool result ends the current assistant text run
        }
        break
      }
@@ -290,9 +293,20 @@ export default function Talk() {
        // conversation.item.create + response.create when it's done.
        handleFunctionCall(event)
        break
-      case 'response.done':
+      case 'response.done': {
+        // A cancelled response (barge-in / interruption) leaves a partial,
+        // incrementally-streamed assistant bubble behind. The server discards
+        // the interrupted item from history; mirror that here (remove the
+        // in-progress assistant entry by item_id) so the regenerated reply
+        // doesn't show up as a second assistant message.
+        if (event.response?.status === 'cancelled' && inProgressIdRef.current) {
+          const id = inProgressIdRef.current
+          inProgressIdRef.current = null
+          setTranscript(prev => prev.filter(e => e.id !== id))
+        }
        updateStatus('listening', 'Listening...')
        break
+      }
      case 'error':
        hasErrorRef.current = true
        updateStatus('error', 'Error: ' + (event.error?.message || 'Unknown error'))
@@ -789,7 +803,7 @@ export default function Talk() {
              const iconColor = isToolCall || isToolResult ? 'var(--color-text-secondary)'
                              : isUser ? 'var(--color-primary)' : 'var(--color-accent)'
              return (
-                <div key={i} style={{ display: 'flex', alignItems: 'flex-start', gap: 'var(--spacing-xs)' }}>
+                <div key={entry.id || i} style={{ display: 'flex', alignItems: 'flex-start', gap: 'var(--spacing-xs)' }}>
                  <i className={iconClass} style={{ color: iconColor, marginTop: 3, flexShrink: 0, fontSize: '0.75rem' }} />
                  <p style={{
                    margin: 0,