diff --git a/scripts/src/hwlab-node-web-observe-runner-source.ts b/scripts/src/hwlab-node-web-observe-runner-source.ts
index e3429d81..6bf9d2f6 100644
--- a/scripts/src/hwlab-node-web-observe-runner-source.ts
+++ b/scripts/src/hwlab-node-web-observe-runner-source.ts
@@ -2023,7 +2023,7 @@ import { createInterface } from "node:readline";
 
 const stateDir = path.resolve(process.env.UNIDESK_WEB_OBSERVE_STATE_DIR || process.argv[2] || ".state/web-observe/manual");
 const archivePrefix = safeArchivePrefix(process.env.UNIDESK_WEB_OBSERVE_ANALYZE_ARCHIVE_PREFIX || "");
-const analyzeTailSamples = positiveInteger(process.env.UNIDESK_WEB_OBSERVE_ANALYZE_TAIL_SAMPLES, 360);
+const analyzeTailSamples = (() => { const parsed = Number(process.env.UNIDESK_WEB_OBSERVE_ANALYZE_TAIL_SAMPLES); return Number.isFinite(parsed) && parsed >= 0 ? Math.floor(parsed) : 360; })();
 const alertThresholds = parseAlertThresholds(process.env.UNIDESK_WEB_OBSERVE_ALERT_THRESHOLDS_JSON);
 const dataDir = archivePrefix ? path.join(stateDir, "archive") : stateDir;
 const dataFile = (name) => path.join(dataDir, archivePrefix ? archivePrefix + "-" + name : name);