audit: make oral B development gate immutable

2 files changed, 9 insertions, 2 deletions

diff --git a/ORAL_B_RECOVERY.md b/ORAL_B_RECOVERY.md
index da018dd..abfcffc 100644
--- a/ORAL_B_RECOVERY.md
+++ b/ORAL_B_RECOVERY.md
@@ -117,7 +117,9 @@ necessity, innovation identification, and a causal plasticity lesion.
 
 The executable runner, complete-grid analyzer, and shell entry point are
 `experiments/bci_td_run.py`, `experiments/analyze_bci_td_development.py`, and
-`experiments/bci_td_development_screen.sh`. None may run before D4 closes.
+`experiments/bci_td_development_screen.sh`. None may run before D4 closes. Once
+the deterministic R1 gate exists, later invocations may only verify exact
+equality and cannot overwrite it.
 
 ## R2 frozen untouched confirmation
 
diff --git a/experiments/analyze_bci_td_development.py b/experiments/analyze_bci_td_development.py
index 78dbceb..5d97c9d 100644
--- a/experiments/analyze_bci_td_development.py
+++ b/experiments/analyze_bci_td_development.py
@@ -206,7 +206,12 @@ def main():
             "R1 is development evidence and cannot change the paper score"),
     }
     if os.path.exists(args.out):
-        raise FileExistsError(f"refusing to overwrite {args.out}")
+        with open(args.out) as handle:
+            existing = json.load(handle)
+        require(existing == output,
+                "existing R1 gate differs from deterministic re-audit")
+        print(json.dumps(output, indent=2))
+        return
     with open(args.out, "w") as handle:
         json.dump(output, handle, indent=2, sort_keys=True)
         handle.write("\n")