} else {
            final String errorCode = UUID.randomUUID().toString();
            message = escapeJsonKeyValue("error_code:", errorCode);
            if (logger.isDebugEnabled()) {
                logger.debug("[{}] {}", errorCode, stacktraceString.get().replace("\n", "\\n"));
            } else if (status >= 500) {
                logger.warn("[{}] {}", errorCode, t.getMessage());
            }
        }

    if (streamId == 0) throw IOException("TYPE_RST_STREAM streamId == 0")
    val errorCodeInt = source.readInt()
    val errorCode =
      ErrorCode.fromHttp2(errorCodeInt) ?: throw IOException(
        "TYPE_RST_STREAM unexpected error code: $errorCodeInt",
      )
    handler.rstStream(streamId, errorCode)
  }

  @Throws(IOException::class)
  private fun readSettings(
    handler: Handler,
    length: Int,

                public void onError(final String phase, final String errorCode) {
                    try {
                        sendSseEvent(writer, "error", Map.of("phase", phase, "message", errorCode, "errorCode", errorCode));
                        if (logger.isDebugEnabled()) {
                            logger.debug("SSE error event sent. phase={}, error={}", phase, errorCode);
                        }

                    logger.warn("Failed to access Web API.", e);
                }
                message = e.getMessage();
            } else {
                final String errorCode = UUID.randomUUID().toString();
                message = "[" + errorCode + "] Failed to access to Web API.";
                if (statusCode >= 400 && statusCode < 500) {
                    if (logger.isDebugEnabled()) {

            var errorMessage = config.labels.error;
            try {
                var data = JSON.parse(e.data);
                if (data.errorCode && config.labels.errors && config.labels.errors[data.errorCode]) {
                    errorMessage = config.labels.errors[data.errorCode];
                } else if (data.message) {
                    errorMessage = data.message;
                }
            } catch (ex) {}

            return new ChatResult(session.getSessionId(), assistantMessage, sources);

        } catch (final LlmException e) {
            logger.warn("[RAG] LLM error during enhanced chat. sessionId={}, errorCode={}, error={}, elapsedTime={}ms",
                    session.getSessionId(), e.getErrorCode(), e.getMessage(), System.currentTimeMillis() - startTime, e);
            callback.onError("llm", e.getErrorCode());