fix(collaboration): preserve active artifact exchanges

internal/tools/delegate_tool.go

@@ -86,6 +86,9 @@ type DelegateTool struct {
 	sweeperStop    chan struct{}
 	sweeperDone    chan struct{}
 
+	activeArtifactMu sync.RWMutex
+	activeArtifacts  map[string]uint32
+
 	completionMu     sync.Mutex
 	completionClosed bool
 	completionWG     sync.WaitGroup
@@ -190,15 +193,16 @@ func NewDelegateToolWithAdmission(
 		admission = orchestration.NewChildRunAdmission(32, 128)
 	}
 	return &DelegateTool{
-		links:       links,
-		agents:      agents,
-		eventBus:    eb,
-		runFn:       runFn,
-		admission:   admission,
-		retained:    make(map[string]retainedDelegationArtifact),
-		sweeperStop: make(chan struct{}),
-		sweeperDone: make(chan struct{}),
-		closeDone:   make(chan struct{}),
+		links:           links,
+		agents:          agents,
+		eventBus:        eb,
+		runFn:           runFn,
+		admission:       admission,
+		retained:        make(map[string]retainedDelegationArtifact),
+		sweeperStop:     make(chan struct{}),
+		sweeperDone:     make(chan struct{}),
+		activeArtifacts: make(map[string]uint32),
+		closeDone:       make(chan struct{}),
 	}
 }
 
@@ -717,6 +721,9 @@ func collectDelegateInputs(callerWorkspace string, explicitInputs, currentMedia
 }
 
 func (t *DelegateTool) runArtifactExchange(ctx context.Context, job *delegateArtifactJob) (dr DelegateResult, returnErr error) {
+	t.beginDelegationArtifactExchange(job.tenantWorkspace, job.delegationID)
+	defer t.endDelegationArtifactExchange(job.tenantWorkspace, job.delegationID)
+
 	exchange, err := NewDelegationArtifactExchange(
 		job.tenantWorkspace,
 		job.tenantID,

internal/tools/delegate_tool_hooks_test.go

@@ -1800,6 +1800,178 @@ func TestDelegateTool_RecoversStaleArtifactLifecycleStates(t *testing.T) {
 	}
 }
 
+func TestDelegateTool_PeriodicArtifactMaintenancePreservesActiveExchange(t *testing.T) {
+	tenantWorkspace := t.TempDir()
+	callerWorkspace := filepath.Join(tenantWorkspace, "agents", "caller")
+	if err := os.MkdirAll(callerWorkspace, 0o750); err != nil {
+		t.Fatal(err)
+	}
+	callerRoot, err := OpenDelegationArtifactRoot(callerWorkspace)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer callerRoot.Close()
+
+	delegationID := uuid.New()
+	runStarted := make(chan struct{})
+	resumeRun := make(chan struct{})
+	var tool *DelegateTool
+	tool = NewDelegateTool(
+		noopAgentLink{},
+		noopAgentCRUD{},
+		nil,
+		func(_ context.Context, req DelegateRequest) (DelegateResult, error) {
+			close(runStarted)
+			<-resumeRun
+			if !tool.delegationArtifactExchangeActive(tenantWorkspace, delegationID) {
+				return DelegateResult{}, errors.New("delegation artifact exchange became inactive during run")
+			}
+			if err := os.WriteFile(
+				filepath.Join(req.DelegateOutputsPath, "result.txt"),
+				[]byte("active result"),
+				0o600,
+			); err != nil {
+				return DelegateResult{}, err
+			}
+			return DelegateResult{Content: "done"}, nil
+		},
+	)
+	tool.workspace = tenantWorkspace
+	defer tool.Close()
+
+	job := &delegateArtifactJob{
+		req:             DelegateRequest{DelegationID: delegationID.String()},
+		callerRoot:      callerRoot,
+		callerWorkspace: callerWorkspace,
+		tenantWorkspace: tenantWorkspace,
+		tenantID:        store.MasterTenantID,
+		delegationID:    delegationID,
+	}
+	job.callerLocation = tool.resolveDelegationCallerLocation(job)
+
+	runDone := make(chan error, 1)
+	go func() {
+		_, err := tool.runArtifactExchange(context.Background(), job)
+		runDone <- err
+	}()
+	select {
+	case <-runStarted:
+	case <-time.After(2 * time.Second):
+		close(resumeRun)
+		t.Fatal("delegated run did not start")
+	}
+	tool.addRetainedDelegationArtifact(retainedDelegationArtifact{
+		tenantWorkspace: tenantWorkspace,
+		tenantID:        store.MasterTenantID,
+		delegationID:    uuid.New(),
+		retainUntil:     time.Now().Add(time.Hour),
+	})
+	tool.maintainDelegationArtifacts(time.Now())
+
+	lifecyclePath := filepath.Join(
+		tenantWorkspace,
+		"collaboration",
+		"delegations",
+		delegationID.String(),
+		delegationArtifactLifecycleFile,
+	)
+	stateBytes, stateErr := os.ReadFile(lifecyclePath)
+	var state delegationArtifactLifecycleState
+	if stateErr == nil {
+		stateErr = json.Unmarshal(stateBytes, &state)
+	}
+	close(resumeRun)
+	runErr := <-runDone
+	if stateErr != nil {
+		t.Fatal(stateErr)
+	}
+	if state.Status != artifactLifecycleRunning {
+		t.Fatalf("active lifecycle status = %q, want %q", state.Status, artifactLifecycleRunning)
+	}
+	if runErr != nil {
+		t.Fatalf("active exchange run after maintenance: %v", runErr)
+	}
+	if tool.delegationArtifactExchangeActive(tenantWorkspace, delegationID) {
+		t.Fatal("completed delegation artifact exchange remained active")
+	}
+	publishedOutput := filepath.Join(
+		callerWorkspace,
+		".delegations",
+		delegationID.String(),
+		"outputs",
+		"result.txt",
+	)
+	if got, err := os.ReadFile(publishedOutput); err != nil || string(got) != "active result" {
+		t.Fatalf("published output = %q, %v", got, err)
+	}
+}
+
+func TestDelegateTool_PeriodicArtifactMaintenanceRecoversUnregisteredExchange(t *testing.T) {
+	tenantWorkspace := t.TempDir()
+	callerWorkspace := filepath.Join(tenantWorkspace, "agents", "caller")
+	if err := os.MkdirAll(callerWorkspace, 0o750); err != nil {
+		t.Fatal(err)
+	}
+	callerRoot, err := OpenDelegationArtifactRoot(callerWorkspace)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer callerRoot.Close()
+
+	delegationID := uuid.New()
+	exchange, err := NewDelegationArtifactExchange(
+		tenantWorkspace,
+		store.MasterTenantID,
+		delegationID,
+		DelegationArtifactLimits{},
+		time.Minute,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer exchange.Close()
+
+	tool := NewDelegateTool(
+		noopAgentLink{},
+		noopAgentCRUD{},
+		nil,
+		func(_ context.Context, _ DelegateRequest) (DelegateResult, error) {
+			return DelegateResult{}, nil
+		},
+	)
+	tool.workspace = tenantWorkspace
+	defer tool.Close()
+
+	job := &delegateArtifactJob{
+		req:             DelegateRequest{DelegationID: delegationID.String()},
+		callerRoot:      callerRoot,
+		callerWorkspace: callerWorkspace,
+		tenantWorkspace: tenantWorkspace,
+		tenantID:        store.MasterTenantID,
+		delegationID:    delegationID,
+	}
+	job.callerLocation = tool.resolveDelegationCallerLocation(job)
+	if err := tool.updateActiveDelegationLifecycle(exchange, job); err != nil {
+		t.Fatalf("update active lifecycle: %v", err)
+	}
+	if err := tool.markDelegationRunning(exchange, job, time.Now()); err != nil {
+		t.Fatalf("mark running: %v", err)
+	}
+
+	tool.maintainDelegationArtifacts(time.Now())
+
+	state, err := readDelegationArtifactLifecycleState(exchange.root, delegationID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if state.Status != artifactLifecycleFailed || state.ReasonCode != "artifact_recovered_stale" {
+		t.Fatalf("unregistered lifecycle = %#v, want recovered stale failure", state)
+	}
+	if _, ok := tool.retained[retainedDelegationArtifactKey(tenantWorkspace, delegationID)]; !ok {
+		t.Fatalf("unregistered exchange was not added to retained registry: %#v", tool.retained)
+	}
+}
+
 func TestDelegateTool_RecoveryPromotesDurablePublishingState(t *testing.T) {
 	tenantWorkspace := t.TempDir()
 	callerWorkspace := filepath.Join(tenantWorkspace, "agents", "caller")

internal/tools/delegation_artifact_janitor.go

@@ -263,6 +263,43 @@ func retainedDelegationArtifactKey(tenantWorkspace string, delegationID uuid.UUI
 	return tenantWorkspace + "\x00" + delegationID.String()
 }
 
+func (t *DelegateTool) beginDelegationArtifactExchange(
+	tenantWorkspace string,
+	delegationID uuid.UUID,
+) {
+	key := retainedDelegationArtifactKey(tenantWorkspace, delegationID)
+	t.activeArtifactMu.Lock()
+	defer t.activeArtifactMu.Unlock()
+	if t.activeArtifacts == nil {
+		t.activeArtifacts = make(map[string]uint32)
+	}
+	t.activeArtifacts[key]++
+}
+
+func (t *DelegateTool) endDelegationArtifactExchange(
+	tenantWorkspace string,
+	delegationID uuid.UUID,
+) {
+	key := retainedDelegationArtifactKey(tenantWorkspace, delegationID)
+	t.activeArtifactMu.Lock()
+	defer t.activeArtifactMu.Unlock()
+	if t.activeArtifacts[key] <= 1 {
+		delete(t.activeArtifacts, key)
+		return
+	}
+	t.activeArtifacts[key]--
+}
+
+func (t *DelegateTool) delegationArtifactExchangeActive(
+	tenantWorkspace string,
+	delegationID uuid.UUID,
+) bool {
+	key := retainedDelegationArtifactKey(tenantWorkspace, delegationID)
+	t.activeArtifactMu.RLock()
+	defer t.activeArtifactMu.RUnlock()
+	return t.activeArtifacts[key] > 0
+}
+
 func (t *DelegateTool) runDelegationArtifactSweeper() {
 	ticker := time.NewTicker(delegationArtifactSweepInterval)
 	defer func() {
@@ -272,14 +309,18 @@ func (t *DelegateTool) runDelegationArtifactSweeper() {
 	for {
 		select {
 		case now := <-ticker.C:
-			t.recoverRetainedDelegationExchanges()
-			t.sweepRetainedDelegationExchanges(now)
+			t.maintainDelegationArtifacts(now)
 		case <-t.sweeperStop:
 			return
 		}
 	}
 }
 
+func (t *DelegateTool) maintainDelegationArtifacts(now time.Time) {
+	t.recoverRetainedDelegationExchanges()
+	t.sweepRetainedDelegationExchanges(now)
+}
+
 func (t *DelegateTool) recoverRetainedDelegationExchanges() {
 	for _, tenantWorkspace := range t.delegationTenantWorkspaces() {
 		if err := t.recoverTenantDelegationExchanges(tenantWorkspace); err != nil {
@@ -350,6 +391,9 @@ func (t *DelegateTool) recoverTenantDelegationExchanges(tenantWorkspace string)
 			}
 			continue
 		}
+		if t.delegationArtifactExchangeActive(tenantWorkspace, delegationID) {
+			continue
+		}
 		exchangeRoot, err := delegationsRoot.openSubroot(name)
 		if err != nil {
 			slog.Warn("delegate.artifact_exchange_recovery_open_failed",