diff --git a/internal/drivers/api_gateway.go b/internal/drivers/api_gateway.go
index 0282daf..5abbf6e 100644
--- a/internal/drivers/api_gateway.go
+++ b/internal/drivers/api_gateway.go
@@ -89,8 +89,7 @@ func (d *APIGatewayDriver) HealthCheck(ctx context.Context, ref interfaces.Resou
 	if err != nil {
 		return &interfaces.HealthResult{Healthy: false, Message: err.Error()}, nil
 	}
-	healthy := app.ActiveDeployment != nil && app.ActiveDeployment.Phase == godo.DeploymentPhase_Active
-	return &interfaces.HealthResult{Healthy: healthy}, nil
+	return appHealthResult(app), nil
 }
 
 func (d *APIGatewayDriver) Scale(_ context.Context, _ interfaces.ResourceRef, _ int) (*interfaces.ResourceOutput, error) {
diff --git a/internal/drivers/api_gateway_test.go b/internal/drivers/api_gateway_test.go
index 49b06c0..ebede1e 100644
--- a/internal/drivers/api_gateway_test.go
+++ b/internal/drivers/api_gateway_test.go
@@ -3,6 +3,7 @@ package drivers_test
 import (
 	"context"
 	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/GoCodeAlone/workflow-plugin-digitalocean/internal/drivers"
@@ -208,3 +209,89 @@ func TestAPIGatewayDriver_HealthCheck_Unhealthy(t *testing.T) {
 		t.Errorf("expected unhealthy when no active deployment")
 	}
 }
+
+// ── APIGateway HealthCheck deployment-phase tests ────────────────────────────
+
+func gwAppWithPhases(active, inProgress, pending *godo.DeploymentPhase) *godo.App {
+	app := &godo.App{ID: "app-gw-999", Spec: &godo.AppSpec{Name: "phased-gw"}}
+	if active != nil {
+		app.ActiveDeployment = &godo.Deployment{Phase: *active}
+	}
+	if inProgress != nil {
+		app.InProgressDeployment = &godo.Deployment{Phase: *inProgress}
+	}
+	if pending != nil {
+		app.PendingDeployment = &godo.Deployment{Phase: *pending}
+	}
+	return app
+}
+
+func gwPhasePtr(p godo.DeploymentPhase) *godo.DeploymentPhase { return &p }
+
+func TestAPIGatewayDriver_HealthCheck_InProgress_Building(t *testing.T) {
+	d := drivers.NewAPIGatewayDriverWithClient(&mockAPIGatewayClient{
+		app: gwAppWithPhases(nil, gwPhasePtr(godo.DeploymentPhase_Building), nil),
+	}, "nyc3")
+	result, err := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-gw", ProviderID: "app-gw-999"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.Healthy {
+		t.Error("expected Healthy=false while BUILDING")
+	}
+	if !strings.Contains(result.Message, "in progress") {
+		t.Errorf("message should contain 'in progress', got: %q", result.Message)
+	}
+}
+
+func TestAPIGatewayDriver_HealthCheck_InProgress_Deploying(t *testing.T) {
+	d := drivers.NewAPIGatewayDriverWithClient(&mockAPIGatewayClient{
+		app: gwAppWithPhases(nil, gwPhasePtr(godo.DeploymentPhase_Deploying), nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-gw", ProviderID: "app-gw-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false while DEPLOYING")
+	}
+	if !strings.Contains(result.Message, "in progress") {
+		t.Errorf("message should contain 'in progress', got: %q", result.Message)
+	}
+}
+
+func TestAPIGatewayDriver_HealthCheck_InProgress_Failed(t *testing.T) {
+	d := drivers.NewAPIGatewayDriverWithClient(&mockAPIGatewayClient{
+		app: gwAppWithPhases(nil, gwPhasePtr(godo.DeploymentPhase_Error), nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-gw", ProviderID: "app-gw-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false for ERROR phase")
+	}
+	if !strings.Contains(result.Message, "failed") {
+		t.Errorf("message should contain 'failed', got: %q", result.Message)
+	}
+}
+
+func TestAPIGatewayDriver_HealthCheck_PendingDeployment(t *testing.T) {
+	d := drivers.NewAPIGatewayDriverWithClient(&mockAPIGatewayClient{
+		app: gwAppWithPhases(nil, nil, gwPhasePtr(godo.DeploymentPhase_PendingBuild)),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-gw", ProviderID: "app-gw-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false with only a pending deployment")
+	}
+	if !strings.Contains(result.Message, "queued") {
+		t.Errorf("message should contain 'queued', got: %q", result.Message)
+	}
+}
+
+func TestAPIGatewayDriver_HealthCheck_NoDeployment(t *testing.T) {
+	d := drivers.NewAPIGatewayDriverWithClient(&mockAPIGatewayClient{
+		app: gwAppWithPhases(nil, nil, nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-gw", ProviderID: "app-gw-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false with no deployments")
+	}
+	if !strings.Contains(result.Message, "no deployment") {
+		t.Errorf("message should contain 'no deployment', got: %q", result.Message)
+	}
+}
diff --git a/internal/drivers/app_platform.go b/internal/drivers/app_platform.go
index 7b52abc..527716d 100644
--- a/internal/drivers/app_platform.go
+++ b/internal/drivers/app_platform.go
@@ -170,12 +170,50 @@ func (d *AppPlatformDriver) HealthCheck(ctx context.Context, ref interfaces.Reso
 	if err != nil {
 		return &interfaces.HealthResult{Healthy: false, Message: err.Error()}, nil
 	}
-	healthy := app.ActiveDeployment != nil && app.ActiveDeployment.Phase == godo.DeploymentPhase_Active
-	msg := ""
-	if !healthy {
-		msg = fmt.Sprintf("phase: %v", app.ActiveDeployment)
+	return appHealthResult(app), nil
+}
+
+// appHealthResult evaluates all three DO deployment slots in priority order and
+// returns an accurate HealthResult:
+//
+//   - ActiveDeployment ACTIVE         → Healthy=true
+//   - InProgressDeployment (building) → Healthy=false, "deployment in progress: <phase>"
+//   - InProgressDeployment (failed)   → Healthy=false, "deployment failed: <phase>"
+//   - PendingDeployment               → Healthy=false, "deployment queued"
+//   - none of the above               → Healthy=false, "no deployment found"
+func appHealthResult(app *godo.App) *interfaces.HealthResult {
+	// 1. Active and healthy.
+	if app.ActiveDeployment != nil && app.ActiveDeployment.Phase == godo.DeploymentPhase_Active {
+		return &interfaces.HealthResult{Healthy: true}
 	}
-	return &interfaces.HealthResult{Healthy: healthy, Message: msg}, nil
+
+	// 2. Deployment currently in progress — inspect its phase.
+	if dep := app.InProgressDeployment; dep != nil {
+		switch dep.Phase {
+		case godo.DeploymentPhase_PendingBuild,
+			godo.DeploymentPhase_Building,
+			godo.DeploymentPhase_PendingDeploy,
+			godo.DeploymentPhase_Deploying:
+			return &interfaces.HealthResult{
+				Healthy: false,
+				Message: fmt.Sprintf("deployment in progress: %s", dep.Phase),
+			}
+		default:
+			// ERROR, CANCELED, SUPERSEDED, etc.
+			return &interfaces.HealthResult{
+				Healthy: false,
+				Message: fmt.Sprintf("deployment failed: %s", dep.Phase),
+			}
+		}
+	}
+
+	// 3. Deployment queued but not yet started.
+	if app.PendingDeployment != nil {
+		return &interfaces.HealthResult{Healthy: false, Message: "deployment queued"}
+	}
+
+	// 4. No deployment at all (first-deploy not yet kicked off, or app never deployed).
+	return &interfaces.HealthResult{Healthy: false, Message: "no deployment found"}
 }
 
 func (d *AppPlatformDriver) Scale(ctx context.Context, ref interfaces.ResourceRef, replicas int) (*interfaces.ResourceOutput, error) {
diff --git a/internal/drivers/app_platform_test.go b/internal/drivers/app_platform_test.go
index 22af4f2..23826fe 100644
--- a/internal/drivers/app_platform_test.go
+++ b/internal/drivers/app_platform_test.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/GoCodeAlone/workflow-plugin-digitalocean/internal/drivers"
@@ -334,6 +335,105 @@ func TestAppPlatformDriver_HealthCheck_Unhealthy(t *testing.T) {
 	}
 }
 
+// ── HealthCheck deployment-phase tests ───────────────────────────────────────
+
+func appWithPhases(active, inProgress, pending *godo.DeploymentPhase) *godo.App {
+	app := &godo.App{ID: "app-999", Spec: &godo.AppSpec{Name: "phased-app"}}
+	if active != nil {
+		app.ActiveDeployment = &godo.Deployment{Phase: *active}
+	}
+	if inProgress != nil {
+		app.InProgressDeployment = &godo.Deployment{Phase: *inProgress}
+	}
+	if pending != nil {
+		app.PendingDeployment = &godo.Deployment{Phase: *pending}
+	}
+	return app
+}
+
+func phasePtr(p godo.DeploymentPhase) *godo.DeploymentPhase { return &p }
+
+func TestAppPlatformDriver_HealthCheck_Active(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(phasePtr(godo.DeploymentPhase_Active), nil, nil),
+	}, "nyc3")
+	result, err := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !result.Healthy {
+		t.Errorf("expected Healthy=true for ACTIVE phase, got message: %q", result.Message)
+	}
+}
+
+func TestAppPlatformDriver_HealthCheck_InProgress_Building(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(nil, phasePtr(godo.DeploymentPhase_Building), nil),
+	}, "nyc3")
+	result, err := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.Healthy {
+		t.Error("expected Healthy=false while BUILDING")
+	}
+	if !strings.Contains(result.Message, "in progress") {
+		t.Errorf("message should contain 'in progress', got: %q", result.Message)
+	}
+}
+
+func TestAppPlatformDriver_HealthCheck_InProgress_Deploying(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(nil, phasePtr(godo.DeploymentPhase_Deploying), nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false while DEPLOYING")
+	}
+	if !strings.Contains(result.Message, "in progress") {
+		t.Errorf("message should contain 'in progress', got: %q", result.Message)
+	}
+}
+
+func TestAppPlatformDriver_HealthCheck_InProgress_Failed(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(nil, phasePtr(godo.DeploymentPhase_Error), nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false for ERROR phase")
+	}
+	if !strings.Contains(result.Message, "failed") {
+		t.Errorf("message should contain 'failed', got: %q", result.Message)
+	}
+}
+
+func TestAppPlatformDriver_HealthCheck_PendingDeployment(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(nil, nil, phasePtr(godo.DeploymentPhase_PendingBuild)),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false with only a pending deployment")
+	}
+	if !strings.Contains(result.Message, "queued") {
+		t.Errorf("message should contain 'queued', got: %q", result.Message)
+	}
+}
+
+func TestAppPlatformDriver_HealthCheck_NoDeployment(t *testing.T) {
+	d := drivers.NewAppPlatformDriverWithClient(&mockAppClient{
+		app: appWithPhases(nil, nil, nil),
+	}, "nyc3")
+	result, _ := d.HealthCheck(context.Background(), interfaces.ResourceRef{Name: "phased-app", ProviderID: "app-999"})
+	if result.Healthy {
+		t.Error("expected Healthy=false with no deployments")
+	}
+	if !strings.Contains(result.Message, "no deployment") {
+		t.Errorf("message should contain 'no deployment', got: %q", result.Message)
+	}
+}
+
 // ── ParseImageRef unit tests ──────────────────────────────────────────────────
 
 func TestParseImageRef_DOCR(t *testing.T) {