Fix TypeScript SDK driver: resolve ts-node from workspace-local node_modules/.bin

pkg/workflow/copilot_engine_execution.go

@@ -133,11 +133,11 @@ const copilotSDKPythonPathExpression = "${{ github.workspace }}/.gh-aw/copilot-s
 // SetupActionDestinationShell). For bare command names (no extension), the driver is treated
 // as an arbitrary executable in PATH: runtimeCmd is the command itself and driverArg is empty.
 //
-//   - .js/.cjs/.mjs → ("$GH_AW_NODE_EXEC", "driver.cjs")
-//   - .py           → ("python3",           "driver.py")
-//   - .ts/.mts      → ("ts-node",           "driver.ts")
-//   - .rb           → ("ruby",              "driver.rb")
-//   - (no ext)      → ("my-driver",         "")
+//   - .js/.cjs/.mjs → ("$GH_AW_NODE_EXEC",  "driver.cjs")
+//   - .py           → ("python3",             "driver.py")
+//   - .ts/.mts      → ("$GH_AW_NODE_EXEC",   "driver.ts")
+//   - .rb           → ("ruby",                "driver.rb")
+//   - (no ext)      → ("my-driver",           "")
 func copilotSDKDriverExecArgs(driverName string) (runtimeCmd, driverArg string) {
 	ext := strings.ToLower(filepath.Ext(driverName))
 	switch ext {
@@ -146,7 +146,8 @@ func copilotSDKDriverExecArgs(driverName string) (runtimeCmd, driverArg string)
 	case ".py":
 		return "python3", driverName
 	case ".ts", ".mts":
-		return "ts-node", driverName
+		// Node 24 runs TypeScript natively; use the same node executor as .js drivers.
+		return `"$GH_AW_NODE_EXEC"`, driverName
 	case ".rb":
 		return "ruby", driverName
 	default:

pkg/workflow/copilot_engine_installation.go

@@ -234,19 +234,18 @@ func specToInstallStep(spec copilotSDKInstallSpec) GitHubActionStep {
 
 // sdkDriverInstallCommand returns a synthetic command string for the given driver filename
 // that can be passed to getCopilotSDKInstallSpec/detectRuntimeFromCopilotCommand to select
-// the correct SDK package manager. Python, Ruby, and TypeScript extensions need special
-// handling; JS drivers and arbitrary commands (no extension) fall back to the Node.js default.
+// the correct SDK package manager. Python and Ruby extensions need special handling;
+// JS, TypeScript, and arbitrary commands (no extension) fall back to the Node.js default.
+// TypeScript uses Node.js native support (Node 24+) so no extra toolchain install is needed.
 func sdkDriverInstallCommand(driverName string) string {
 	ext := strings.ToLower(filepath.Ext(driverName))
 	switch ext {
 	case ".py":
 		return "python3 " + driverName
 	case ".rb":
 		return "ruby " + driverName
-	case ".ts", ".mts":
-		return "ts-node " + driverName
 	default:
-		// .js/.cjs/.mjs and no-extension (arbitrary commands) default to Node.js.
+		// .js/.cjs/.mjs, .ts/.mts, and no-extension (arbitrary commands) default to Node.js.
 		return ""
 	}
 }

pkg/workflow/copilot_engine_test.go

@@ -545,14 +545,54 @@ func TestCopilotEngineExecutionStepsWithCopilotSDKTypeScriptDriver(t *testing.T)
 	}
 
 	stepContent := strings.Join([]string(steps[0]), "\n")
-	if !strings.Contains(stepContent, "ts-node") {
-		t.Fatalf("Expected TypeScript SDK driver mode to use ts-node runtime, got:\n%s", stepContent)
+	// The harness is invoked as: <outer-node> copilot_harness.cjs <runtime-cmd> <driver> <copilot-binary>
+	// Verify the runtime argument passed to the harness is GH_AW_NODE_EXEC (native Node, not ts-node).
+	if !strings.Contains(stepContent, `copilot_harness.cjs "$GH_AW_NODE_EXEC"`) {
+		t.Fatalf("Expected TypeScript SDK driver to pass GH_AW_NODE_EXEC as runtime to harness, got:\n%s", stepContent)
+	}
+	if strings.Contains(stepContent, "ts-node") {
+		t.Fatalf("Expected TypeScript SDK driver to NOT use ts-node (Node 24 runs TS natively), got:\n%s", stepContent)
 	}
 	if !strings.Contains(stepContent, "my_driver.ts") {
 		t.Fatalf("Expected SDK driver mode to include my_driver.ts, got:\n%s", stepContent)
 	}
 }
 
+// TestCopilotSDKDriverExecArgs directly verifies the runtime command returned for each
+// driver file extension, ensuring TypeScript uses native Node.js (not ts-node).
+func TestCopilotSDKDriverExecArgs(t *testing.T) {
+	tests := []struct {
+		driver         string
+		wantRuntime    string
+		wantDriverArg  string
+		wantNotRuntime string
+	}{
+		{driver: "agent.js", wantRuntime: `"$GH_AW_NODE_EXEC"`, wantDriverArg: "agent.js"},
+		{driver: "agent.cjs", wantRuntime: `"$GH_AW_NODE_EXEC"`, wantDriverArg: "agent.cjs"},
+		{driver: "agent.mjs", wantRuntime: `"$GH_AW_NODE_EXEC"`, wantDriverArg: "agent.mjs"},
+		{driver: "agent.ts", wantRuntime: `"$GH_AW_NODE_EXEC"`, wantDriverArg: "agent.ts", wantNotRuntime: "ts-node"},
+		{driver: "agent.mts", wantRuntime: `"$GH_AW_NODE_EXEC"`, wantDriverArg: "agent.mts", wantNotRuntime: "ts-node"},
+		{driver: "agent.py", wantRuntime: "python3", wantDriverArg: "agent.py"},
+		{driver: "agent.rb", wantRuntime: "ruby", wantDriverArg: "agent.rb"},
+		{driver: "my-driver", wantRuntime: "my-driver", wantDriverArg: ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.driver, func(t *testing.T) {
+			runtime, driverArg := copilotSDKDriverExecArgs(tt.driver)
+			if runtime != tt.wantRuntime {
+				t.Errorf("copilotSDKDriverExecArgs(%q) runtime = %q, want %q", tt.driver, runtime, tt.wantRuntime)
+			}
+			if driverArg != tt.wantDriverArg {
+				t.Errorf("copilotSDKDriverExecArgs(%q) driverArg = %q, want %q", tt.driver, driverArg, tt.wantDriverArg)
+			}
+			if tt.wantNotRuntime != "" && runtime == tt.wantNotRuntime {
+				t.Errorf("copilotSDKDriverExecArgs(%q) runtime = %q, must NOT be %q", tt.driver, runtime, tt.wantNotRuntime)
+			}
+		})
+	}
+}
+
 func TestCopilotEngineExecutionStepsWithCopilotSDKRubyDriver(t *testing.T) {
 	engine := NewCopilotEngine()
 	workflowData := &WorkflowData{
@@ -2236,6 +2276,13 @@ func TestCopilotEngineInstallationWithCommandAndCopilotSDK(t *testing.T) {
 			expectedRun:   "npm install --ignore-scripts --no-save @github/copilot-sdk@" + string(constants.DefaultCopilotSDKVersion),
 			expectedSteps: 1,
 		},
+		{
+			name:          "ts-node command installs ts-node and typescript alongside sdk",
+			command:       "ts-node driver.ts",
+			expectedName:  "name: Install GitHub Copilot SDK (TypeScript)",
+			expectedRun:   "npm install --ignore-scripts --no-save @github/copilot-sdk@" + string(constants.DefaultCopilotSDKVersion) + " ts-node typescript",
+			expectedSteps: 1,
+		},
 		{
 			name:          "env wrapper command is detected",
 			command:       "env FOO=bar python script.py",
@@ -2314,10 +2361,10 @@ func TestCopilotEngineInstallationWithCopilotSDKDriver(t *testing.T) {
 			expectedRun:  "python3 -m pip install --disable-pip-version-check --target \"${GITHUB_WORKSPACE}/.gh-aw/copilot-sdk/python\" github-copilot-sdk==" + string(constants.DefaultCopilotSDKVersion),
 		},
 		{
-			name:         "typescript driver installs ts-node toolchain and sdk",
+			name:         "typescript driver uses node sdk install (node 24 native ts support)",
 			driver:       "my_driver.ts",
-			expectedName: "name: Install GitHub Copilot SDK (TypeScript)",
-			expectedRun:  "npm install --ignore-scripts --no-save @github/copilot-sdk@" + string(constants.DefaultCopilotSDKVersion) + " ts-node typescript",
+			expectedName: "name: Install GitHub Copilot SDK (Node.js)",
+			expectedRun:  "npm install --ignore-scripts --no-save @github/copilot-sdk@" + string(constants.DefaultCopilotSDKVersion),
 		},
 		{
 			name:         "ruby driver uses npm sdk install fallback",

pkg/workflow/runtime_detection.go

@@ -2,6 +2,7 @@ package workflow
 
 import (
 	"maps"
+	"path/filepath"
 	"strings"
 
 	"github.com/github/gh-aw/pkg/constants"
@@ -84,6 +85,17 @@ func DetectRuntimeRequirements(workflowData *WorkflowData) []RuntimeRequirement
 		}
 	}
 
+	// When using a TypeScript Copilot SDK driver (.ts/.mts extension), require Node 24.
+	// Node 24 runs TypeScript natively; earlier versions do not support this.
+	// This only applies to file-extension-based driver detection, not to engine.command
+	// configurations (e.g. "ts-node driver.ts") which manage their own toolchain.
+	if requiresNode24ForTypeScriptSDKDriver(workflowData) {
+		nodeRuntime := findRuntimeByID("node")
+		if nodeRuntime != nil {
+			updateRequiredRuntime(nodeRuntime, string(constants.DefaultNodeVersion), requirements)
+		}
+	}
+
 	// Detect runtimes required by LSP server configurations.
 	// Each known LSP server declares the runtime it needs (e.g. "go" for gopls,
 	// "ruby" for solargraph). Feeding these through the runtime manager ensures
@@ -150,6 +162,27 @@ func requiresNodeForEngineHarness(workflowData *WorkflowData) bool {
 	return strings.EqualFold(engineID, string(constants.CopilotEngine))
 }
 
+// requiresNode24ForTypeScriptSDKDriver returns true when a Copilot SDK driver is a TypeScript
+// file (.ts or .mts) detected by extension. Node 24 runs TypeScript natively; the runtime
+// setup ensures the correct version is provisioned.
+//
+// This does not apply when engine.command is set (e.g., "ts-node driver.ts"), since those
+// configurations manage their own TypeScript toolchain independently.
+func requiresNode24ForTypeScriptSDKDriver(workflowData *WorkflowData) bool {
+	if workflowData == nil || workflowData.EngineConfig == nil {
+		return false
+	}
+	if !workflowData.EngineConfig.CopilotSDK {
+		return false
+	}
+	// engine.command takes precedence; the user manages the toolchain explicitly.
+	if workflowData.EngineConfig.Command != "" {
+		return false
+	}
+	ext := filepath.Ext(workflowData.EngineConfig.Driver)
+	return strings.EqualFold(ext, ".ts") || strings.EqualFold(ext, ".mts")
+}
+
 func detectFromInlineEngineDriver(workflowData *WorkflowData, requirements map[string]*RuntimeRequirement) {
 	if workflowData == nil || workflowData.EngineConfig == nil || workflowData.EngineConfig.InlineDriver == nil {
 		return

pkg/workflow/runtime_setup_test.go

@@ -1251,3 +1251,62 @@ func TestDetectRuntimeRequirements_CustomDriverDoesNotAddNodeForNonCopilotEngine
 		}
 	}
 }
+
+// TestDetectRuntimeRequirements_TypeScriptSDKDriverAddsNode24 verifies that a Copilot SDK
+// workflow with a .ts/.mts driver requires Node 24 for native TypeScript execution.
+func TestDetectRuntimeRequirements_TypeScriptSDKDriverAddsNode24(t *testing.T) {
+	tests := []struct {
+		name   string
+		driver string
+	}{
+		{name: ".ts driver", driver: "my_driver.ts"},
+		{name: ".mts driver", driver: "my_driver.mts"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			data := &WorkflowData{
+				RunsOn: "runs-on: ubuntu-latest",
+				EngineConfig: &EngineConfig{
+					CopilotSDK: true,
+					Driver:     tt.driver,
+				},
+			}
+
+			requirements := DetectRuntimeRequirements(data)
+
+			var nodeReq *RuntimeRequirement
+			for i := range requirements {
+				if requirements[i].Runtime != nil && requirements[i].Runtime.ID == "node" {
+					nodeReq = &requirements[i]
+					break
+				}
+			}
+
+			require.NotNil(t, nodeReq, "Expected Node.js 24 runtime requirement for TypeScript SDK driver %q", tt.driver)
+			assert.Equal(t, string(constants.DefaultNodeVersion), nodeReq.Version,
+				"TypeScript SDK driver %q should require Node.js %s for native TypeScript support", tt.driver, constants.DefaultNodeVersion)
+		})
+	}
+}
+
+// TestDetectRuntimeRequirements_TypeScriptSDKCommandDoesNotAddNode24 verifies that when
+// engine.command is set (e.g., ts-node driver.ts), no automatic Node 24 requirement is added,
+// since the user manages the toolchain via engine.command.
+func TestDetectRuntimeRequirements_TypeScriptSDKCommandDoesNotAddNode24(t *testing.T) {
+	data := &WorkflowData{
+		RunsOn: "runs-on: ubuntu-latest",
+		EngineConfig: &EngineConfig{
+			CopilotSDK: true,
+			Command:    "ts-node driver.ts",
+		},
+	}
+
+	requirements := DetectRuntimeRequirements(data)
+
+	for _, req := range requirements {
+		if req.Runtime != nil && req.Runtime.ID == "node" && req.Version == string(constants.DefaultNodeVersion) {
+			t.Fatalf("Expected no explicit Node 24 requirement when engine.command is set (ts-node manages its own toolchain), got Node version %q", req.Version)
+		}
+	}
+}