fix(kanban): judge unachievable goals as blocked, never done

hermes_cli/kanban.py

@@ -2311,18 +2311,23 @@ def _worker_run_id_for(task_id: str) -> Optional[int]:
         return None
 
 
-def _goal_mode_handoff_rejection(task: Optional[kb.Task], evidence: str) -> Optional[str]:
-    """Apply the goal judge to every terminal worker handoff, including review."""
+def _goal_mode_handoff_rejection(task: Optional[kb.Task], evidence: str):
+    """Apply the goal judge to every terminal worker handoff, including review.
+
+    Returns ``(verdict, reason_or_None)`` — ``"done"`` allows the handoff;
+    ``"blocked"`` means the judge ruled the goal unachievable (#100954);
+    ``"continue"``/``"wait"`` reject with the judge's reason.
+    """
     if task is None or not task.goal_mode:
-        return None
+        return ("done", None)
     try:
         from agent.auxiliary_client import get_text_auxiliary_client
 
         client, model = get_text_auxiliary_client("goal_judge")
     except Exception:
-        return None
+        return ("done", None)
     if client is None or not model:
-        return None
+        return ("done", None)
 
     from hermes_cli.goals import judge_goal
 
@@ -2341,7 +2346,7 @@ def _goal_mode_handoff_rejection(task: Optional[kb.Task], evidence: str) -> Opti
             judge_exc,
             exc_info=True,
         )
-    return reason if verdict != "done" else None
+    return (verdict, None if verdict == "done" else reason)
 
 
 def _cmd_complete(args: argparse.Namespace) -> int:
@@ -2379,11 +2384,21 @@ def _cmd_complete(args: argparse.Namespace) -> int:
             # to every terminal handoff so request-review cannot bypass the
             # acceptance contract that protects complete.
             task = kb.get_task(conn, tid)
-            rejection = _goal_mode_handoff_rejection(
+            gate_verdict, rejection = _goal_mode_handoff_rejection(
                 task,
                 (summary or args.result or "").strip(),
             )
-            if rejection is not None:
+            if gate_verdict == "blocked":
+                print(
+                    f"kanban: goal completion of {tid} rejected: judge ruled "
+                    f"the goal unachievable — {rejection}. Re-scope with "
+                    f"kanban edit, or record the block with kanban block "
+                    f"instead of completing.",
+                    file=sys.stderr,
+                )
+                failed.append(tid)
+                continue
+            if gate_verdict == "continue" or rejection is not None:
                 print(
                     f"kanban: goal completion of {tid} rejected by judge: {rejection}. "
                     f"Provide evidence matching the task's acceptance criteria.",
@@ -2532,11 +2547,19 @@ def _cmd_request_review(args: argparse.Namespace) -> int:
             return 2
     reviewer = getattr(args, "reviewer", None)
     with kb.connect_closing() as conn:
-        rejection = _goal_mode_handoff_rejection(
+        gate_verdict, rejection = _goal_mode_handoff_rejection(
             kb.get_task(conn, tid),
             summary or "",
         )
-        if rejection is not None:
+        if gate_verdict == "blocked":
+            print(
+                f"kanban: goal review handoff of {tid} rejected: judge ruled "
+                f"the goal unachievable — {rejection}. Record the block with "
+                f"kanban block instead of requesting review.",
+                file=sys.stderr,
+            )
+            return 1
+        if gate_verdict == "continue" or rejection is not None:
             print(
                 f"kanban: goal review handoff of {tid} rejected by judge: "
                 f"{rejection}. Provide acceptance evidence matching the task.",