diff --git a/cli/clitest/clitest.go b/cli/clitest/clitest.go
index 5a7160ffd8..b1fb85e473 100644
--- a/cli/clitest/clitest.go
+++ b/cli/clitest/clitest.go
@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"errors"
 	"io"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -52,6 +53,9 @@ func SetupConfig(t *testing.T, client *codersdk.Client, root config.Root) {
 // new temporary testing directory.
 func CreateTemplateVersionSource(t *testing.T, responses *echo.Responses) string {
 	directory := t.TempDir()
+	f, err := ioutil.TempFile(directory, "*.tf")
+	require.NoError(t, err)
+	f.Close()
 	data, err := echo.Tar(responses)
 	require.NoError(t, err)
 	extractTar(t, data, directory)
diff --git a/provisionersdk/archive.go b/provisionersdk/archive.go
index 941b144bfc..17df9be844 100644
--- a/provisionersdk/archive.go
+++ b/provisionersdk/archive.go
@@ -16,12 +16,47 @@ const (
 	TemplateArchiveLimit = 1 << 20
 )
 
-// Tar archives a directory.
+func dirHasExt(dir string, ext string) (bool, error) {
+	dirEnts, err := os.ReadDir(dir)
+	if err != nil {
+		return false, err
+	}
+
+	for _, fi := range dirEnts {
+		if strings.HasSuffix(fi.Name(), ext) {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
+// Tar archives a Terraform directory.
 func Tar(directory string, limit int64) ([]byte, error) {
 	var buffer bytes.Buffer
 	tarWriter := tar.NewWriter(&buffer)
 	totalSize := int64(0)
-	err := filepath.Walk(directory, func(file string, fileInfo os.FileInfo, err error) error {
+
+	const tfExt = ".tf"
+	hasTf, err := dirHasExt(directory, tfExt)
+	if err != nil {
+		return nil, err
+	}
+	if !hasTf {
+		absPath, err := filepath.Abs(directory)
+		if err != nil {
+			return nil, err
+		}
+
+		// Show absolute path to aid in debugging. E.g. showing "." is
+		// useless.
+		return nil, xerrors.Errorf(
+			"%s is not a valid template since it has no %s files",
+			absPath, tfExt,
+		)
+	}
+
+	err = filepath.Walk(directory, func(file string, fileInfo os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}
diff --git a/provisionersdk/archive_test.go b/provisionersdk/archive_test.go
index 7abe9ce47b..4fb80ff296 100644
--- a/provisionersdk/archive_test.go
+++ b/provisionersdk/archive_test.go
@@ -12,18 +12,30 @@ import (
 
 func TestTar(t *testing.T) {
 	t.Parallel()
-	dir := t.TempDir()
-	file, err := os.CreateTemp(dir, "")
-	require.NoError(t, err)
-	_ = file.Close()
-	_, err = provisionersdk.Tar(dir, 1024)
-	require.NoError(t, err)
+	t.Run("NoTF", func(t *testing.T) {
+		t.Parallel()
+		dir := t.TempDir()
+		file, err := os.CreateTemp(dir, "")
+		require.NoError(t, err)
+		_ = file.Close()
+		_, err = provisionersdk.Tar(dir, 1024)
+		require.Error(t, err)
+	})
+	t.Run("Valid", func(t *testing.T) {
+		t.Parallel()
+		dir := t.TempDir()
+		file, err := os.CreateTemp(dir, "*.tf")
+		require.NoError(t, err)
+		_ = file.Close()
+		_, err = provisionersdk.Tar(dir, 1024)
+		require.NoError(t, err)
+	})
 }
 
 func TestUntar(t *testing.T) {
 	t.Parallel()
 	dir := t.TempDir()
-	file, err := os.CreateTemp(dir, "")
+	file, err := os.CreateTemp(dir, "*.tf")
 	require.NoError(t, err)
 	_ = file.Close()
 	archive, err := provisionersdk.Tar(dir, 1024)
diff --git a/pty/ptytest/ptytest.go b/pty/ptytest/ptytest.go
index 4f67568c8f..a6d6d8ab46 100644
--- a/pty/ptytest/ptytest.go
+++ b/pty/ptytest/ptytest.go
@@ -133,7 +133,7 @@ func (p *PTY) ExpectMatch(str string) string {
 		p.logf("matched %q = %q", str, buffer.String())
 		return buffer.String()
 	case <-timeout.Done():
-		// Ensure goroutine is cleaned up before test exit.
+		// Ensure gorouine is cleaned up before test exit.
 		_ = p.out.closeErr(p.Close())
 		<-match