diff --git a/internal/runtime/executor/codex_websockets_executor.go b/internal/runtime/executor/codex_websockets_executor.go
index 87ae0efe4..d6f1de86b 100644
--- a/internal/runtime/executor/codex_websockets_executor.go
+++ b/internal/runtime/executor/codex_websockets_executor.go
@@ -868,7 +868,7 @@ func applyCodexWebsocketHeaders(ctx context.Context, headers http.Header, auth *
 		if auth != nil && auth.Metadata != nil {
 			if accountID, ok := auth.Metadata["account_id"].(string); ok {
 				if trimmed := strings.TrimSpace(accountID); trimmed != "" {
-					headers.Set("ChatGPT-Account-ID", trimmed)
+					setHeaderCasePreserved(headers, "ChatGPT-Account-ID", trimmed)
 				}
 			}
 		}
@@ -1040,7 +1040,9 @@ func parseCodexWebsocketError(payload []byte) (error, bool) {
 	out := buildCodexWebsocketErrorPayload(payload, status)
 	headers := parseCodexWebsocketErrorHeaders(payload)
 	statusError := statusErr{code: status, msg: string(out)}
-	if isCodexWebsocketConnectionLimitError(payload) {
+	if retryAfter := parseCodexRetryAfter(status, out, time.Now()); retryAfter != nil {
+		statusError.retryAfter = retryAfter
+	} else if isCodexWebsocketConnectionLimitError(payload) {
 		retryAfter := time.Duration(0)
 		statusError.retryAfter = &retryAfter
 	}
diff --git a/internal/runtime/executor/codex_websockets_executor_test.go b/internal/runtime/executor/codex_websockets_executor_test.go
index 0b7a546e9..bf12ef786 100644
--- a/internal/runtime/executor/codex_websockets_executor_test.go
+++ b/internal/runtime/executor/codex_websockets_executor_test.go
@@ -296,9 +296,16 @@ func TestApplyCodexWebsocketHeadersUsesCanonicalAccountHeader(t *testing.T) {
 
 	headers := applyCodexWebsocketHeaders(context.Background(), http.Header{}, auth, "", nil)
 
-	if got := headers.Get("ChatGPT-Account-ID"); got != "acct-1" {
+	if got := headerValueCaseInsensitive(headers, "ChatGPT-Account-ID"); got != "acct-1" {
 		t.Fatalf("ChatGPT-Account-ID = %s, want acct-1", got)
 	}
+	values, ok := headers["ChatGPT-Account-ID"]
+	if !ok {
+		t.Fatalf("expected exact ChatGPT-Account-ID key, got %#v", headers)
+	}
+	if len(values) != 1 || values[0] != "acct-1" {
+		t.Fatalf("ChatGPT-Account-ID values = %#v, want [acct-1]", values)
+	}
 }
 
 func TestBuildCodexResponsesWebsocketURLRequiresHTTPURL(t *testing.T) {
@@ -326,12 +333,30 @@ func TestParseCodexWebsocketErrorMarksConnectionLimitRetryable(t *testing.T) {
 	if !ok || retryable.RetryAfter() == nil {
 		t.Fatalf("expected retryable websocket connection limit error")
 	}
+	if got := *retryable.RetryAfter(); got != 0 {
+		t.Fatalf("retryAfter = %v, want connection-limit fallback 0", got)
+	}
 	withHeaders, ok := err.(interface{ Headers() http.Header })
 	if !ok || withHeaders.Headers().Get("retry-after") != "1" {
 		t.Fatalf("headers = %#v, want retry-after", err)
 	}
 }
 
+func TestParseCodexWebsocketErrorUsesUsageLimitRetryMetadata(t *testing.T) {
+	err, ok := parseCodexWebsocketError([]byte(`{"type":"error","status":429,"body":{"error":{"type":"usage_limit_reached","message":"usage limit reached","resets_in_seconds":7}}}`))
+	if !ok {
+		t.Fatalf("expected websocket error")
+	}
+
+	retryable, ok := err.(interface{ RetryAfter() *time.Duration })
+	if !ok || retryable.RetryAfter() == nil {
+		t.Fatalf("expected retryable usage limit websocket error")
+	}
+	if got := *retryable.RetryAfter(); got != 7*time.Second {
+		t.Fatalf("retryAfter = %v, want 7s", got)
+	}
+}
+
 func TestParseCodexWebsocketErrorPreservesWrappedBodyAndHeaders(t *testing.T) {
 	err, ok := parseCodexWebsocketError([]byte(`{"type":"error","status":429,"body":{"error":{"code":"websocket_connection_limit_reached","type":"server_error","message":"too many websocket connections"}},"headers":{"x-request-id":"req-1"}}`))
 	if !ok {