diff --git a/internal/adapter/codeagent/claudecode/adapter.go b/internal/adapter/codeagent/claudecode/adapter.go
index ec7841f..3347c1c 100644
--- a/internal/adapter/codeagent/claudecode/adapter.go
+++ b/internal/adapter/codeagent/claudecode/adapter.go
@@ -162,6 +162,8 @@ func (a *Adapter) Execute(ctx context.Context, req *domain.AgentRequest, handler
 	}
 
 	// Determine exit code and error
+	stdoutStr := finalOutput.String()
+	stderrStr := stderrOutput.String()
 	if cmdErr != nil {
 		if exitErr, ok := cmdErr.(*exec.ExitError); ok {
 			result.ExitCode = exitErr.ExitCode()
@@ -169,17 +171,17 @@ func (a *Adapter) Execute(ctx context.Context, req *domain.AgentRequest, handler
 			result.ExitCode = 1
 			result.Error = cmdErr
 		}
-		// Include stderr and troubleshooting help in error
-		result.Error = a.buildErrorWithHelp(result.Error, stderrOutput.String(), namespace, podName)
+		// Include stdout, stderr, and troubleshooting help in error
+		result.Error = a.buildErrorWithHelp(result.Error, stderrStr, stdoutStr, namespace, podName)
 	} else if parseErr != nil {
 		result.ExitCode = 1
-		result.Error = a.buildErrorWithHelp(parseErr, stderrOutput.String(), namespace, podName)
+		result.Error = a.buildErrorWithHelp(parseErr, stderrStr, stdoutStr, namespace, podName)
 	} else if resultMsg != nil && !resultMsg.IsSuccess() {
 		result.ExitCode = 1
 		if resultMsg.Error != "" {
-			result.Error = a.buildErrorWithHelp(fmt.Errorf("%s", resultMsg.Error), stderrOutput.String(), namespace, podName)
+			result.Error = a.buildErrorWithHelp(fmt.Errorf("%s", resultMsg.Error), stderrStr, stdoutStr, namespace, podName)
 		} else {
-			result.Error = a.buildErrorWithHelp(nil, stderrOutput.String(), namespace, podName)
+			result.Error = a.buildErrorWithHelp(nil, stderrStr, stdoutStr, namespace, podName)
 		}
 	}
 
@@ -320,8 +322,8 @@ func (a *Adapter) streamStderrCapture(r io.Reader, handler domain.AgentEventHand
 	}
 }
 
-// buildErrorWithHelp creates an error message with stderr output and troubleshooting help.
-func (a *Adapter) buildErrorWithHelp(err error, stderr, namespace, podName string) error {
+// buildErrorWithHelp creates an error message with captured output and troubleshooting help.
+func (a *Adapter) buildErrorWithHelp(err error, stderr, stdout, namespace, podName string) error {
 	var msg strings.Builder
 
 	if err != nil {
@@ -330,6 +332,12 @@ func (a *Adapter) buildErrorWithHelp(err error, stderr, namespace, podName strin
 		msg.WriteString("claude command failed")
 	}
 
+	// Include stdout if it contains useful output (e.g. auth errors that Claude writes to stdout)
+	if stdout != "" {
+		msg.WriteString("\n\noutput:\n")
+		msg.WriteString(stdout)
+	}
+
 	// Include stderr if available
 	if stderr != "" {
 		msg.WriteString("\n\nstderr:\n")
diff --git a/internal/worker/build_executor.go b/internal/worker/build_executor.go
index 7754d6a..8d9f0a0 100644
--- a/internal/worker/build_executor.go
+++ b/internal/worker/build_executor.go
@@ -221,9 +221,15 @@ func (b *BuildExecutor) Execute(ctx context.Context, task *domain.WorkTask) *dom
 		}
 	}
 
+	// Use streamed output, but fall back to agent's captured output if streaming missed it
+	output := outputBuilder.String()
+	if output == "" && agentResult.FinalOutput != "" {
+		output = agentResult.FinalOutput
+	}
+
 	result := &domain.BuildResult{
 		Success:    agentResult.Success(),
-		Output:     outputBuilder.String(),
+		Output:     output,
 		DurationMs: time.Since(start).Milliseconds(),
 		Artifacts:  make(map[string]string),
 	}