Include elimination info in debate prompts so remaining debaters stop referencing eliminated participants

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/backend/app/services/debate.py b/backend/app/services/debate.py
index 086dde1..fa63985 100644
--- a/backend/app/services/debate.py
+++ b/backend/app/services/debate.py
@@ -24,6 +24,12 @@ def _format_history(debate_history: List[Dict[str, Any]]) -> str:
         text += f"\n--- Round {rn} ---\n"
         for resp in past_round["responses"]:
             text += f"\n[{resp['model']}]:\n{resp['response']}\n"
+        for elim in past_round.get("eliminated", []):
+            convinced_by = elim.get("convinced_by")
+            if convinced_by:
+                text += f"\n[{elim['model']} was convinced by {convinced_by} and left the debate]\n"
+            else:
+                text += f"\n[{elim['model']} conceded and left the debate]\n"
     return text
 
 
@@ -496,9 +502,14 @@ async def debate_event_stream(
 
                 # Process eliminations
                 eliminated_this_round = []
+                eliminated_details = []
                 for cfg, result in zip(active_configs, results):
                     if result["convinced"]:
                         eliminated_this_round.append(cfg.model_name)
+                        eliminated_details.append({
+                            "model": cfg.model_name,
+                            "convinced_by": result.get("convinced_by"),
+                        })
                         yield _sse_event({
                             "type": "model_eliminated",
                             "data": {
@@ -509,6 +520,10 @@ async def debate_event_stream(
                             },
                         })
 
+                # Store elimination info in debate history so prompts include it
+                if eliminated_details:
+                    debate_history[-1]["eliminated"] = eliminated_details
+
                 # Remove eliminated models from active list
                 if eliminated_this_round:
                     active_indices = [