--- R9 before e34067edef2eba03c1e40bca7d2b2d933ae12b85
+++ R9 after dd3b029f5325ae8e67ca89f37c426bdbe92449e6
@@ -23,14 +23,13 @@
 {"ordinal": 1, "status": "running", "turn": "ROOT_TURN_1", "type": "provider_turn.updated"}
 {"lastError": null, "status": "running", "type": "provider_session.updated"}
 {"ordinal": 1, "status": "running", "turn": "ROOT_TURN_1", "type": "provider_turn.updated"}
-{"lastError": "Synthetic overflow O1", "status": "error", "type": "provider_session.updated"}
+{"lastError": "Synthetic ordinary failure", "status": "error", "type": "provider_session.updated"}
 {"ordinal": 1, "status": "failed", "turn": "ROOT_TURN_1", "type": "provider_turn.updated"}
-{"lastError": "Synthetic overflow O1", "status": "error", "type": "provider_session.updated"}
-{"failure": {"class": "provider_error", "code": "ContextOverflowError", "message": "Synthetic overflow O1", "retryable": null}, "failureItemOrdinal": 101, "runOrdinal": 1, "status": "failed", "threadDisposition": "reusable", "turn": "ROOT_TURN_1", "type": "turn.terminal"}
 {"lastError": "Synthetic ordinary failure", "status": "error", "type": "provider_session.updated"}
+{"failure": {"class": "provider_error", "code": "APIError", "message": "Synthetic ordinary failure", "retryable": null}, "failureItemOrdinal": 101, "runOrdinal": 1, "status": "failed", "threadDisposition": "reusable", "turn": "ROOT_TURN_1", "type": "turn.terminal"}
 {"label": "ordinary-error-is-immediate", "session": {"lastError": "Synthetic ordinary failure", "status": "error"}, "terminalCount": 1, "turns": [{"status": "running", "turn": "ROOT_TURN_1"}, {"status": "running", "turn": "ROOT_TURN_1"}, {"status": "failed", "turn": "ROOT_TURN_1"}], "type": "checkpoint"}
 {"label": "capture-end", "session": {"lastError": "Synthetic ordinary failure", "status": "error"}, "terminalCount": 1, "turns": [{"status": "running", "turn": "ROOT_TURN_1"}, {"status": "running", "turn": "ROOT_TURN_1"}, {"status": "failed", "turn": "ROOT_TURN_1"}], "type": "checkpoint"}
-{"terminalCount": 1, "terminals": [{"failure": {"class": "provider_error", "code": "ContextOverflowError", "message": "Synthetic overflow O1", "retryable": null}, "status": "failed", "threadDisposition": "reusable", "turn": "ROOT_TURN_1"}], "type": "capture-outcome"}
+{"terminalCount": 1, "terminals": [{"failure": {"class": "provider_error", "code": "APIError", "message": "Synthetic ordinary failure", "retryable": null}, "status": "failed", "threadDisposition": "reusable", "turn": "ROOT_TURN_1"}], "type": "capture-outcome"}
 {"fixture": "UNIT R9-name-fallback"}
 {"ordinal": 1, "status": "running", "turn": "ROOT_TURN_1", "type": "provider_turn.updated"}
 {"lastError": null, "status": "running", "type": "provider_session.updated"}