Fix goalless auto-restart: handle placeholder goal and headless EOFError

_resolve_goal now recognizes the hook placeholder "(no goal set...)" and
continues with a fallback instead of using it as a real goal. Also catches
EOFError/KeyboardInterrupt from input() so headless mode exits cleanly
instead of crashing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: jvalin17

scripts/auto_continue.py

@@ -83,7 +83,12 @@ def run(self) -> int:
             )
 
     def _resolve_goal(self) -> str:
-        """Goal from: arg > HANDOFF.md > interactive prompt."""
+        """Goal from: arg > HANDOFF.md > interactive prompt > empty string.
+
+        When HANDOFF.md exists (auto-restart), a missing goal is acceptable —
+        the agent reads HANDOFF.md itself. When no HANDOFF.md and no arg,
+        try interactive prompt but handle headless (EOFError) gracefully.
+        """
         if self.goal:
             return self.goal
 
@@ -96,10 +101,18 @@ def _resolve_goal(self) -> str:
                 re.DOTALL,
             )
             if goal_match:
-                return goal_match.group(1).strip()
-
-        # Interactive prompt
-        return input("What's the goal? ")
+                extracted = goal_match.group(1).strip()
+                # Ignore hook placeholder — treat as "no goal" but continue
+                if not extracted.startswith("(no goal"):
+                    return extracted
+            # HANDOFF.md exists but no real goal — continue anyway
+            return "(continued from HANDOFF.md)"
+
+        # Interactive prompt — handle headless mode
+        try:
+            return input("What's the goal? ")
+        except (EOFError, KeyboardInterrupt):
+            return ""
 
     def _build_prompt(self) -> str:
         """Build the prompt for the Claude session."""

tests/test_auto_continue.py

@@ -297,6 +297,32 @@ def mock_launch(prompt):
 # --- CLI parsing ---
 
 
+class TestGoallessRestart:
+    """Bug: auto-restart without goal arg should work when HANDOFF.md exists."""
+
+    def test_no_goal_arg_with_handoff_continues(self, project_dir):
+        """When HANDOFF.md exists but no goal arg, wrapper should continue (not block on input)."""
+        handoff = (
+            "# HANDOFF\n\n## Goal\n\n"
+            "(no goal set — check project-state.md)\n\n"
+            "## Session\n\nNumber: 3\n"
+        )
+        (project_dir / "HANDOFF.md").write_text(handoff)
+
+        runner = AutoContinue(goal=None, max_budget=None, project_dir=project_dir, dry_run=True)
+        # Should NOT call input() — should resolve goal from handoff or use fallback
+        result = runner.run()
+        assert result == 0
+
+    def test_no_goal_no_handoff_returns_error_in_headless(self, project_dir):
+        """No goal + no HANDOFF.md + non-interactive = exit 1, not hang on input()."""
+        runner = AutoContinue(goal=None, max_budget=None, project_dir=project_dir)
+        # Simulate non-interactive (stdin closed)
+        with patch("builtins.input", side_effect=EOFError):
+            result = runner.run()
+        assert result == 1
+
+
 class TestParseArgs:
     def test_goal_positional(self):
         args = parse_args(["Build auth system"])