diff --git a/pkg/ai-stream/bridgev2/events.go b/pkg/ai-stream/bridgev2/events.go
index 7781c5ea..1fe09a3a 100644
--- a/pkg/ai-stream/bridgev2/events.go
+++ b/pkg/ai-stream/bridgev2/events.go
@@ -69,6 +69,22 @@ func ApprovalPrompt(portalKey networkid.PortalKey, sender networkid.UserID, ctx
 	}
 }
 
+func FinalEditExtra(extra map[string]any) map[string]any {
+	out := make(map[string]any, len(extra)+1)
+	for key, value := range extra {
+		out[key] = value
+	}
+	out["com.beeper.stream"] = nil
+	return out
+}
+
+func FinalEditTopLevelExtra() map[string]any {
+	return map[string]any{
+		"com.beeper.dont_render_edited": true,
+		"com.beeper.stream":             nil,
+	}
+}
+
 func FinalMetadataEdit(portalKey networkid.PortalKey, sender networkid.UserID, messageID networkid.MessageID, run aistream.Run, timestamp time.Time) *simplevent.Message[*aistream.Run] {
 	finalContent, finalExtra := aimatrix.FinalContent(run)
 	return FinalMetadataEditWithContent(portalKey, sender, messageID, run, finalContent, finalExtra, timestamp)
@@ -86,13 +102,11 @@ func FinalMetadataEditWithContent(portalKey networkid.PortalKey, sender networki
 			}
 			return &bridgev2.ConvertedEdit{
 				ModifiedParts: []*bridgev2.ConvertedEditPart{{
-					Part:    existing[0],
-					Type:    event.EventMessage,
-					Content: finalContent,
-					Extra:   finalExtra,
-					TopLevelExtra: map[string]any{
-						"com.beeper.dont_render_edited": true,
-					},
+					Part:          existing[0],
+					Type:          event.EventMessage,
+					Content:       finalContent,
+					Extra:         FinalEditExtra(finalExtra),
+					TopLevelExtra: FinalEditTopLevelExtra(),
 				}},
 			}, nil
 		},
diff --git a/pkg/ai-stream/bridgev2/events_test.go b/pkg/ai-stream/bridgev2/events_test.go
index aaf9f77a..ae461e5c 100644
--- a/pkg/ai-stream/bridgev2/events_test.go
+++ b/pkg/ai-stream/bridgev2/events_test.go
@@ -104,9 +104,19 @@ func TestFinalMetadataEditUsesCompactAnchorContent(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	ai, ok := converted.ModifiedParts[0].Extra[aistream.BeeperAIKey].(aistream.BeeperAI)
+	part := converted.ModifiedParts[0]
+	ai, ok := part.Extra[aistream.BeeperAIKey].(aistream.BeeperAI)
 	if !ok || ai.Kind != aistream.AIKindFinal {
-		t.Fatalf("final metadata edit missing final AI payload: %#v", converted.ModifiedParts[0].Extra)
+		t.Fatalf("final metadata edit missing final AI payload: %#v", part.Extra)
+	}
+	if stream, ok := part.Extra["com.beeper.stream"]; !ok || stream != nil {
+		t.Fatalf("final metadata edit must clear stream in m.new_content: %#v", part.Extra)
+	}
+	if stream, ok := part.TopLevelExtra["com.beeper.stream"]; !ok || stream != nil {
+		t.Fatalf("final metadata edit must clear stream at top level: %#v", part.TopLevelExtra)
+	}
+	if part.TopLevelExtra["com.beeper.dont_render_edited"] != true {
+		t.Fatalf("final metadata edit missing no-render-edited marker: %#v", part.TopLevelExtra)
 	}
 }
 
diff --git a/pkg/ai-stream/run.go b/pkg/ai-stream/run.go
index 991f5032..335dc803 100644
--- a/pkg/ai-stream/run.go
+++ b/pkg/ai-stream/run.go
@@ -182,6 +182,7 @@ type ArtifactSummary struct {
 type Writer struct {
 	Run                       *Run
 	builder                   agui.EventBuilder
+	now                       func() time.Time
 	textMessages              map[int]string
 	textOpen                  map[int]bool
 	textContentWritten        bool
@@ -237,6 +238,7 @@ func NewWriter(run *Run, now func() time.Time) *Writer {
 	writer := &Writer{
 		Run:                  run,
 		builder:              agui.NewEventBuilder(run.Model, now),
+		now:                  now,
 		textMessages:         map[int]string{},
 		textOpen:             map[int]bool{},
 		textIndexOffset:      textIndexOffset,
@@ -252,6 +254,15 @@ func NewWriter(run *Run, now func() time.Time) *Writer {
 	return writer
 }
 
+func (w *Writer) SetModel(model string) {
+	model = strings.TrimSpace(model)
+	if w == nil || w.Run == nil || model == "" {
+		return
+	}
+	w.Run.Model = model
+	w.builder = agui.NewEventBuilder(model, w.now)
+}
+
 func (w *Writer) Add(evt agui.Event) {
 	if w == nil || w.Run == nil || evt.Len() == 0 {
 		return
diff --git a/pkg/ai-stream/stream_test.go b/pkg/ai-stream/stream_test.go
index 9a26db12..09fd06fb 100644
--- a/pkg/ai-stream/stream_test.go
+++ b/pkg/ai-stream/stream_test.go
@@ -30,6 +30,21 @@ func TestPackRunDoesNotSplitOrTruncateBySize(t *testing.T) {
 	}
 }
 
+func TestWriterSetModelUpdatesRunAndFutureEventEnvelopes(t *testing.T) {
+	run := NewRun("run-1", "thread-1", "old/model", "ai", "AI", time.Unix(10, 0))
+	writer := NewWriter(run, func() time.Time { return time.Unix(10, 0) })
+	writer.Start()
+	writer.SetModel("new/model")
+	writer.Text("hello")
+
+	if run.Model != "new/model" {
+		t.Fatalf("run model = %q, want new/model", run.Model)
+	}
+	if got := run.Events[len(run.Events)-1].Get("model"); got != "new/model" {
+		t.Fatalf("future event model = %#v, want new/model", got)
+	}
+}
+
 func TestPackRunDoesNotPutFinalizationTotalsOnStreamEnvelopes(t *testing.T) {
 	run := NewRun("run-1", "thread-1", DefaultModel, "ai", "AI", time.Unix(10, 0))
 	writer := NewWriter(run, func() time.Time { return time.Unix(10, 0) })
diff --git a/pkg/connector/client.go b/pkg/connector/client.go
index 8dd82adc..0d8f3cfb 100644
--- a/pkg/connector/client.go
+++ b/pkg/connector/client.go
@@ -988,13 +988,11 @@ func (cl *Client) assistantFinalEditWithProjection(portalKey networkid.PortalKey
 		}
 		return &bridgev2.ConvertedEdit{
 			ModifiedParts: []*bridgev2.ConvertedEditPart{{
-				Part:    existing[0],
-				Type:    event.EventMessage,
-				Content: projection.Content,
-				Extra:   projection.Extra,
-				TopLevelExtra: map[string]any{
-					"com.beeper.dont_render_edited": true,
-				},
+				Part:          existing[0],
+				Type:          event.EventMessage,
+				Content:       projection.Content,
+				Extra:         aibridgev2.FinalEditExtra(projection.Extra),
+				TopLevelExtra: aibridgev2.FinalEditTopLevelExtra(),
 			}},
 		}, nil
 	}
diff --git a/pkg/connector/stream_test.go b/pkg/connector/stream_test.go
index 305c9d93..88952098 100644
--- a/pkg/connector/stream_test.go
+++ b/pkg/connector/stream_test.go
@@ -1008,6 +1008,13 @@ func TestAssistantEventMetadataCanBeFinalizedBeforeInsert(t *testing.T) {
 	if profile == nil || profile.ID != string(aiid.ModelContactID("beeper", "gpt-5")) || profile.Displayname != "gpt-5" || !profile.HasFallback {
 		t.Fatalf("assistant final edit missing model profile: %#v", profile)
 	}
+	part := converted.ModifiedParts[0]
+	if stream, ok := part.Extra["com.beeper.stream"]; !ok || stream != nil {
+		t.Fatalf("assistant final edit must clear stream in m.new_content: %#v", part.Extra)
+	}
+	if stream, ok := part.TopLevelExtra["com.beeper.stream"]; !ok || stream != nil {
+		t.Fatalf("assistant final edit must clear stream at top level: %#v", part.TopLevelExtra)
+	}
 }
 
 func TestAssistantFallbackEventsUseStrictMatrixOrder(t *testing.T) {