Remove unconditional stateful-turn truncation

README.md

@@ -219,11 +219,12 @@ Training use is tracked separately as `SFT_FULL`, `SFT_STEP_ONLY`,
    score.
 
 For a complete trajectory, the quality call also sees its final model patch. A
-truncated prefix never receives that suffix-derived patch. Every non-success
-trajectory (`resolved=0` or `-1`) is capped before its first statically detected
-state-changing assistant turn. The effective boundary is the earlier of this
-local cap and the GLM boundary. This intentionally prefers a shorter, safer
-investigation trace.
+truncated prefix never receives that suffix-derived patch. State-changing turns
+are recorded as audit telemetry but are not automatic boundaries: writing code
+is not itself an error, and recovered experiments are useful process data. The
+effective boundary is the earliest unrecovered major or critical behavior found
+by the boundary stage. The isolated quality stage rejects a retained prefix that
+still contains an unrecovered severe problem.
 
 Successful trajectories skip boundary selection and are scored as complete
 trajectories. The command remains simple:

changelog.md

@@ -4,6 +4,19 @@ This file records strategy changes that materially affect dataset decisions or
 training-data semantics. Generated audit manifests are not treated as stable API
 contracts.
 
+## Unreleased
+
+### Strategy correction
+
+- Removed the unconditional cutoff before the first state-changing turn for
+  failed and unverified trajectories. A write or edit is not evidence of an
+  error by itself, and this cap discarded normal implementation, recovery, and
+  verification work.
+- The semantic boundary now remains the earliest unrecovered major or critical
+  assistant behavior selected by the boundary stage. The isolated prefix-quality
+  stage remains the safety gate. The first stateful turn is retained as telemetry
+  for paired evaluation against the former policy.
+
 ## 2.0.0 - 2026-08-07
 
 ### Strategy

src/swe_data_processing/audit.py

@@ -72,30 +72,23 @@ def materialize_prefix(
 def effective_boundary_policy(
     record: dict[str, Any], model_result: dict[str, Any]
 ) -> dict[str, Any]:
-    """Choose a conservative effective boundary for one trajectory.
+    """Use the semantic boundary while retaining the old cap as telemetry.
 
-    A failed or unverified record may not retain a statically detected
-    state-changing assistant turn. This deliberately favors a shorter
-    investigation prefix over a late semantic boundary that could retain a bad
-    implementation.
+    A state-changing turn is not evidence of an error by itself. Normal coding,
+    failed experiments, recovery, and verification are useful process data, so
+    the first stateful turn must not become an unconditional cutoff. Prefix
+    safety is enforced independently by the isolated quality stage.
     """
 
     model_boundary = model_result["truncate_before_turn"]
     first_stateful = min(
         extract_static_signals(record)["stateful_turns"], default=None
     )
-    candidates = []
     if model_result["decision"] == "TRUNCATE":
-        candidates.append((model_boundary, "MODEL_BOUNDARY"))
-    if int(record.get("resolved", -1)) != 1 and first_stateful is not None:
-        candidates.append((first_stateful, "NON_SUCCESS_FIRST_STATEFUL_CAP"))
-
-    if candidates:
-        boundary, source = min(candidates, key=lambda item: item[0])
         return {
             "decision": "TRUNCATE",
-            "truncate_before_turn": boundary,
-            "source": source,
+            "truncate_before_turn": model_boundary,
+            "source": "MODEL_BOUNDARY",
             "model_truncate_before_turn": model_boundary,
             "first_stateful_turn": first_stateful,
         }

tests/test_audit.py

@@ -140,7 +140,7 @@ def test_unrecovered_major_issue_is_locally_invalid() -> None:
 
 
 @pytest.mark.parametrize("resolved", [0, -1])
-def test_non_success_outcome_is_capped_before_first_stateful_turn(resolved: int) -> None:
+def test_non_success_outcome_is_not_capped_at_first_stateful_turn(resolved: int) -> None:
     record = _record()
     record["resolved"] = resolved
     record["tools"] = [
@@ -159,9 +159,34 @@ def test_non_success_outcome_is_capped_before_first_stateful_turn(resolved: int)
     result = _boundary()
     result.update(decision="KEEP_FULL", truncate_before_turn=None)
     policy = effective_boundary_policy(record, result)
+    assert policy["decision"] == "KEEP_FULL"
+    assert policy["truncate_before_turn"] is None
+    assert policy["source"] == "MODEL_DECISION"
+    assert policy["first_stateful_turn"] == 3
+
+
+def test_semantic_boundary_is_not_replaced_by_earlier_stateful_turn() -> None:
+    record = _record()
+    record["resolved"] = 0
+    record["tools"] = [
+        {"type": "function", "function": {"name": "str_replace_editor"}}
+    ]
+    record["trajectory"][2]["tool_calls"] = [
+        {
+            "id": "call-1",
+            "type": "function",
+            "function": {
+                "name": "str_replace_editor",
+                "arguments": '{"command":"str_replace","path":"src/a.py"}',
+            },
+        }
+    ]
+    result = _boundary()
+    policy = effective_boundary_policy(record, result)
     assert policy["decision"] == "TRUNCATE"
-    assert policy["truncate_before_turn"] == 3
-    assert policy["source"] == "NON_SUCCESS_FIRST_STATEFUL_CAP"
+    assert policy["truncate_before_turn"] == 5
+    assert policy["source"] == "MODEL_BOUNDARY"
+    assert policy["first_stateful_turn"] == 3
 
 
 def test_boundary_payload_hides_outcome_and_patch_metadata() -> None: