fix(coderd/x/chatd): keep quickgen out of chat sessions

coderd/x/chatd/model_routing_aibridge.go

@@ -27,6 +27,19 @@ const (
 	aibridgeDelegatedBYOKMarker = "delegated"
 )
 
+// Synthetic quickgen calls are still routed through AI Bridge, but they should
+// not become promptless root cards in the user's chat session timeline.
+type suppressAIBridgeSessionHeadersKey struct{}
+
+func contextWithoutAIBridgeSessionHeaders(ctx context.Context) context.Context {
+	return context.WithValue(ctx, suppressAIBridgeSessionHeadersKey{}, true)
+}
+
+func suppressAIBridgeSessionHeadersFromContext(ctx context.Context) bool {
+	suppress, _ := ctx.Value(suppressAIBridgeSessionHeadersKey{}).(bool)
+	return suppress
+}
+
 type aiGatewayModelRoute struct {
 	Provider          database.AIProvider
 	ModelProviderHint string
@@ -76,6 +89,10 @@ type aiGatewayRoundTripper struct {
 func (t *aiGatewayRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	ctx := aibridge.WithDelegatedAPIKeyID(req.Context(), t.apiKeyID)
 	cloned := req.Clone(ctx)
+	if suppressAIBridgeSessionHeadersFromContext(req.Context()) {
+		cloned.Header.Del(chatprovider.HeaderCoderChatID)
+		cloned.Header.Del(chatprovider.HeaderCoderSubchatID)
+	}
 	for name, value := range t.providerAuth.Headers {
 		cloned.Header.Set(name, value)
 	}

coderd/x/chatd/model_routing_internal_test.go

@@ -1,6 +1,7 @@
 package chatd
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
 	"io"
@@ -374,6 +375,66 @@ func TestAIGatewayModelForwardsProviderAuth(t *testing.T) {
 	})
 }
 
+func TestAIGatewayRoundTripperCanSuppressSessionHeaders(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name        string
+		ctx         func() context.Context
+		wantChatID  string
+		wantSubchat string
+	}{
+		{
+			name:        "preserves session headers by default",
+			ctx:         func() context.Context { return t.Context() },
+			wantChatID:  "chat-id",
+			wantSubchat: "subchat-id",
+		},
+		{
+			name: "suppresses session headers when marked",
+			ctx: func() context.Context {
+				return contextWithoutAIBridgeSessionHeaders(t.Context())
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			seen := make(chan http.Header, 1)
+			rt := &aiGatewayRoundTripper{
+				base: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+					seen <- req.Header.Clone()
+					return &http.Response{
+						StatusCode: http.StatusOK,
+						Header:     http.Header{},
+						Body:       io.NopCloser(strings.NewReader("")),
+						Request:    req,
+					}, nil
+				}),
+				apiKeyID: uuid.NewString(),
+			}
+			req, err := http.NewRequestWithContext(tt.ctx(), http.MethodPost, "http://coder-aibridge/v1/responses", nil)
+			require.NoError(t, err)
+			req.Header.Set(chatprovider.HeaderCoderOwnerID, "owner-id")
+			req.Header.Set(chatprovider.HeaderCoderChatID, "chat-id")
+			req.Header.Set(chatprovider.HeaderCoderSubchatID, "subchat-id")
+			req.Header.Set(chatprovider.HeaderCoderWorkspaceID, "workspace-id")
+
+			resp, err := rt.RoundTrip(req)
+			require.NoError(t, err)
+			require.NoError(t, resp.Body.Close())
+
+			got := <-seen
+			require.Equal(t, "owner-id", got.Get(chatprovider.HeaderCoderOwnerID))
+			require.Equal(t, tt.wantChatID, got.Get(chatprovider.HeaderCoderChatID))
+			require.Equal(t, tt.wantSubchat, got.Get(chatprovider.HeaderCoderSubchatID))
+			require.Equal(t, "workspace-id", got.Get(chatprovider.HeaderCoderWorkspaceID))
+		})
+	}
+}
+
 func TestActiveTurnAPIKeyIDFromMessages(t *testing.T) {
 	t.Parallel()
 

coderd/x/chatd/quickgen.go

@@ -495,6 +495,7 @@ func generateStructuredTitleWithUsage(
 		return "", fantasy.Usage{}, xerrors.New("title input was empty")
 	}
 
+	ctx = contextWithoutAIBridgeSessionHeaders(ctx)
 	prompt := syntheticObjectGenerationPrompt(systemPrompt, userInput)
 
 	var maxOutputTokens int64 = 256
@@ -922,6 +923,7 @@ func generateStructuredTurnStatusLabel(
 		return "", xerrors.New("turn status label input was empty")
 	}
 
+	ctx = contextWithoutAIBridgeSessionHeaders(ctx)
 	prompt := syntheticObjectGenerationPrompt(systemPrompt, userInput)
 
 	var maxOutputTokens int64 = 64

coderd/x/chatd/quickgen_internal_test.go

@@ -415,8 +415,9 @@ func TestMaybeGenerateChatTitlePreservesUpdatedAt(t *testing.T) {
 
 	const wantTitle = "Failed workspace logs"
 	model := &chattest.FakeModel{
-		GenerateObjectFn: func(_ context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
+		GenerateObjectFn: func(ctx context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
 			require.Equal(t, "propose_title", call.SchemaName)
+			requireSyntheticQuickgenContext(ctx, t)
 			requireSyntheticQuickgenPrompt(t, call.Prompt, userPrompt)
 			return &fantasy.ObjectResponse{
 				Object: map[string]any{"title": wantTitle},
@@ -495,6 +496,7 @@ func Test_generateManualTitle_UsesTimeout(t *testing.T) {
 				deadline,
 				2*time.Second,
 			)
+			requireSyntheticQuickgenContext(ctx, t)
 			requireSyntheticQuickgenPrompt(t, call.Prompt, "refresh chat title")
 			require.Equal(t, "propose_title", call.SchemaName)
 			return &fantasy.ObjectResponse{Object: map[string]any{"title": "Refresh title"}}, nil
@@ -524,7 +526,8 @@ func Test_generateManualTitle_TruncatesFirstUserInput(t *testing.T) {
 	}
 
 	model := &chattest.FakeModel{
-		GenerateObjectFn: func(_ context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
+		GenerateObjectFn: func(ctx context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
+			requireSyntheticQuickgenContext(ctx, t)
 			requireSyntheticQuickgenPrompt(t, call.Prompt, truncateRunes(longFirstUserText, maxLatestUserMessageRunes))
 			// The manual title system prompt also includes the latest user excerpt.
 			systemText, ok := call.Prompt[0].Content[0].(fantasy.TextPart)
@@ -764,6 +767,12 @@ func openAICompatTestModel(t *testing.T, baseURL string) fantasy.LanguageModel {
 	return model
 }
 
+func requireSyntheticQuickgenContext(ctx context.Context, t *testing.T) {
+	t.Helper()
+
+	require.True(t, suppressAIBridgeSessionHeadersFromContext(ctx))
+}
+
 func requireSyntheticQuickgenPrompt(t *testing.T, prompt fantasy.Prompt, userInput string) {
 	t.Helper()
 
@@ -804,8 +813,9 @@ func TestGenerateStructuredTurnStatusLabel(t *testing.T) {
 		t.Parallel()
 
 		model := &chattest.FakeModel{
-			GenerateObjectFn: func(_ context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
+			GenerateObjectFn: func(ctx context.Context, call fantasy.ObjectCall) (*fantasy.ObjectResponse, error) {
 				require.Equal(t, "propose_turn_status_label", call.SchemaName)
+				requireSyntheticQuickgenContext(ctx, t)
 				requireSyntheticQuickgenPrompt(t, call.Prompt, "done")
 				return &fantasy.ObjectResponse{
 					Object: map[string]any{"label": "Submitted PR"},