diff --git a/agents/services/base_runtime.go b/agents/services/base_runtime.go
index d870ccc9..1cf009f2 100644
--- a/agents/services/base_runtime.go
+++ b/agents/services/base_runtime.go
@@ -226,8 +226,9 @@ func (s *RuntimeWrapper) TestResponseWithResults(run, passed, failed, skipped in
 func (s *RuntimeWrapper) TestError(err error) (*runtimev0.TestResponse, error) {
 	s.Lock()
 	defer s.Unlock()
-	s.TestStatus = &runtimev0.TestStatus{State: runtimev0.TestStatus_ERROR, Message: err.Error(), Failure: operationFailure("runtime.test", err, err.Error())}
-	return &runtimev0.TestResponse{Status: s.TestStatus}, nil
+	message := err.Error()
+	s.TestStatus = &runtimev0.TestStatus{State: runtimev0.TestStatus_ERROR, Message: message, Failure: operationFailure("runtime.test", err, message)}
+	return typedTestErrorResponse(s.TestStatus, message), nil
 }
 
 func (s *RuntimeWrapper) TestErrorf(err error, msg string, args ...any) (*runtimev0.TestResponse, error) {
@@ -235,7 +236,18 @@ func (s *RuntimeWrapper) TestErrorf(err error, msg string, args ...any) (*runtim
 	defer s.Unlock()
 	message := ErrorMessage(err, msg, args...)
 	s.TestStatus = &runtimev0.TestStatus{State: runtimev0.TestStatus_ERROR, Message: message, Failure: operationFailure("runtime.test", err, message)}
-	return &runtimev0.TestResponse{Status: s.TestStatus}, nil
+	return typedTestErrorResponse(s.TestStatus, message), nil
+}
+
+// typedTestErrorResponse makes pre-execution failures terminal and explicit.
+// A status-only response decodes as TestRunResult_UNKNOWN and loses the
+// distinction between a failed test and an environment that never ran tests.
+func typedTestErrorResponse(status *runtimev0.TestStatus, message string) *runtimev0.TestResponse {
+	return &runtimev0.TestResponse{
+		Status: status,
+		Result: &runtimev0.TestRunResult{State: runtimev0.TestRunResult_ERRORED, Message: message},
+		Counts: &runtimev0.TestCounts{},
+	}
 }
 
 // ── Build ─────────────────────────────────────────────────
diff --git a/agents/services/error_contract_test.go b/agents/services/error_contract_test.go
index 70923ca8..4b7715b9 100644
--- a/agents/services/error_contract_test.go
+++ b/agents/services/error_contract_test.go
@@ -22,6 +22,22 @@ func TestRuntimeErrorHelperReturnsStructuredResponseWithoutTransportError(t *tes
 	}
 }
 
+func TestRuntimeTestErrorIsTypedTerminalResponse(t *testing.T) {
+	wrapper := &RuntimeWrapper{}
+	response, err := wrapper.TestError(errors.New("module preparation failed"))
+	if err != nil {
+		t.Fatalf("TestError returned transport error: %v", err)
+	}
+	if response.GetStatus().GetState() != runtimev0.TestStatus_ERROR ||
+		response.GetResult().GetState() != runtimev0.TestRunResult_ERRORED ||
+		response.GetResult().GetMessage() != "module preparation failed" || response.GetCounts() == nil {
+		t.Fatalf("TestError response = %+v, want ERROR/ERRORED with explicit zero counts", response)
+	}
+	if response.GetStatus().GetFailure().GetOperation() != "runtime.test" {
+		t.Fatalf("TestError failure = %+v", response.GetStatus().GetFailure())
+	}
+}
+
 func TestRuntimeLintErrorPreservesFailureOutput(t *testing.T) {
 	wrapper := &RuntimeWrapper{}
 	response, err := wrapper.LintErrorf(errors.New("main.go:4:2: undefined: value"), "lint failed")
diff --git a/runners/golang/formula.go b/runners/golang/formula.go
index d26dd9f9..14e612de 100644
--- a/runners/golang/formula.go
+++ b/runners/golang/formula.go
@@ -105,6 +105,10 @@ func ClassifyEnvError(raw string, runErr error) (reason, detail string) {
 			return EnvErrorToolchainMissing, execErr.Error()
 		}
 	}
+	classificationText := raw
+	if runErr != nil {
+		classificationText = strings.TrimSpace(strings.Join([]string{classificationText, runErr.Error()}, "\n"))
+	}
 	for _, marker := range []string{
 		"errors parsing go.mod",
 		"unknown directive:",
@@ -116,8 +120,8 @@ func ClassifyEnvError(raw string, runErr error) (reason, detail string) {
 		"cannot load module",
 		"unsupported toolchain",
 	} {
-		if idx := strings.Index(raw, marker); idx >= 0 {
-			rest := raw[idx:]
+		if idx := strings.Index(classificationText, marker); idx >= 0 {
+			rest := classificationText[idx:]
 			line := rest
 			if nl := strings.IndexByte(rest, '\n'); nl >= 0 {
 				line = rest[:nl]
diff --git a/runners/golang/formula_test.go b/runners/golang/formula_test.go
index ed21a892..b5aa2293 100644
--- a/runners/golang/formula_test.go
+++ b/runners/golang/formula_test.go
@@ -2,6 +2,7 @@ package golang
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
@@ -236,6 +237,13 @@ func TestRunFormula_BrokenGoModIsEnvBlocked(t *testing.T) {
 	}
 }
 
+func TestClassifyEnvErrorReadsPreExecutionError(t *testing.T) {
+	reason, detail := ClassifyEnvError("", errors.New("prepare Go dependencies: go: errors parsing go.mod:\ngo.mod:1: unknown directive: modle"))
+	if reason != EnvErrorModuleBroken || !strings.Contains(detail, "unknown directive") {
+		t.Fatalf("ClassifyEnvError = %q/%q, want module-broken with parser detail", reason, detail)
+	}
+}
+
 func TestRunFormula_CompileErrorIsNotEnvBlocked(t *testing.T) {
 	dir := writeModule(t, map[string]string{
 		"go.mod":           "module example.com/stringsx\n\ngo 1.21\n",
diff --git a/runners/golang/runner.go b/runners/golang/runner.go
index 2bd822c5..b2e9c3cd 100644
--- a/runners/golang/runner.go
+++ b/runners/golang/runner.go
@@ -1,6 +1,7 @@
 package golang
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"io"
@@ -8,6 +9,7 @@ import (
 	"os/exec"
 	"path"
 	"path/filepath"
+	"strings"
 
 	"github.com/codefly-dev/core/builders"
 	"github.com/codefly-dev/core/resources"
@@ -436,9 +438,12 @@ func (r *GoRunnerEnvironment) GoModuleHandling(ctx context.Context) error {
 		if err != nil {
 			return w.Wrapf(err, "cannot create go mod download process for %s", dir)
 		}
+		var output bytes.Buffer
+		writer := io.Writer(&output)
 		if r.out != nil {
-			proc.WithOutput(r.out)
+			writer = io.MultiWriter(r.out, &output)
 		}
+		proc.WithOutput(writer)
 		proc.WithDir(dir)
 		// Ambient parent workspaces are disabled; a workspace owned by the
 		// attached source root remains authoritative for all module work.
@@ -446,6 +451,9 @@ func (r *GoRunnerEnvironment) GoModuleHandling(ctx context.Context) error {
 			proc.WithEnvironmentVariables(ctx, resources.Env("GOWORK", "off"))
 		}
 		if err := proc.Run(ctx); err != nil {
+			if detail := strings.TrimSpace(output.String()); detail != "" {
+				return w.Wrapf(err, "cannot run go mod download in %s: %s", dir, detail)
+			}
 			return w.Wrapf(err, "cannot run go mod download in %s", dir)
 		}
 	}
diff --git a/runners/golang/runner_test.go b/runners/golang/runner_test.go
index b2a51ccd..942b055c 100644
--- a/runners/golang/runner_test.go
+++ b/runners/golang/runner_test.go
@@ -140,6 +140,21 @@ func TestGoModuleHandlingCacheAdvancesOnlyOnDownloadSuccess(t *testing.T) {
 	})
 }
 
+func TestGoModuleHandlingPreservesParserDiagnostics(t *testing.T) {
+	ctx := context.Background()
+	root := t.TempDir()
+	require.NoError(t, os.WriteFile(filepath.Join(root, "go.mod"), []byte("modle example.com/broken\n\ngo 1.21\n"), 0o644))
+	env, err := golang.NewNativeGoRunner(ctx, root, ".")
+	require.NoError(t, err)
+	env.WithLocalCacheDir(t.TempDir())
+	t.Cleanup(func() { require.NoError(t, env.Shutdown(context.Background())) })
+
+	err = env.GoModuleHandling(ctx)
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "errors parsing go.mod")
+	require.Contains(t, err.Error(), "unknown directive: modle")
+}
+
 func TestGoRunnerInitDoesNotResolveOrMutateProjectDependencies(t *testing.T) {
 	ctx := context.Background()
 	t.Setenv("GOPROXY", "off")