diff --git a/scripts/android-app-i18n.ts b/scripts/android-app-i18n.ts
index f72c5e0a44c..588bf3b977b 100644
--- a/scripts/android-app-i18n.ts
+++ b/scripts/android-app-i18n.ts
@@ -1,6 +1,7 @@
 import { readdir, readFile } from "node:fs/promises";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { NATIVE_I18N_LOCALES } from "./native-app-i18n.ts";
 
 const HERE = path.dirname(fileURLToPath(import.meta.url));
@@ -63,7 +64,8 @@ export async function checkAndroidAppI18n() {
     readAndroidSource(),
     Promise.all(LOCALES.map(readStrings)),
   ]);
-  const [base, ...translations] = localeStrings;
+  const base = expectDefined(localeStrings[0], "English Android string resources");
+  const translations = localeStrings.slice(1);
   const baseKeys = new Set(base.keys());
   const problems: Array<readonly [string, string[]]> = translations.flatMap((strings, index) => {
     const locale = NATIVE_I18N_LOCALES[index];
diff --git a/scripts/apple-app-i18n.ts b/scripts/apple-app-i18n.ts
index 005e2c1f57c..628d7353fdc 100644
--- a/scripts/apple-app-i18n.ts
+++ b/scripts/apple-app-i18n.ts
@@ -1,6 +1,7 @@
 import { mkdir, readFile, writeFile } from "node:fs/promises";
 import path from "node:path";
 import { fileURLToPath, pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { NATIVE_I18N_LOCALES } from "./native-app-i18n.ts";
 
 const HERE = path.dirname(fileURLToPath(import.meta.url));
@@ -196,7 +197,7 @@ export async function checkAppleAppI18n() {
 
 export async function compileMacosLocalizations(outputDir: string) {
   await checkAppleAppI18n();
-  const spec = CATALOGS[1];
+  const spec = expectDefined(CATALOGS[1], "macOS localization catalog specification");
   const catalog = JSON.parse(await readFile(path.join(ROOT, spec.path), "utf8")) as Catalog;
   if (!catalog.strings) {
     throw new Error(`invalid Apple string catalog: ${spec.path}`);
diff --git a/scripts/bench-cli-startup.ts b/scripts/bench-cli-startup.ts
index 691a122495a..affb00029ac 100644
--- a/scripts/bench-cli-startup.ts
+++ b/scripts/bench-cli-startup.ts
@@ -4,6 +4,7 @@ import { mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "nod
 import os from "node:os";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { parseStrictIntegerOption } from "./lib/dev-tooling-safety.ts";
 
 type CommandCase = {
@@ -474,7 +475,7 @@ function parseRepeatableFlag(flag: string): string[] {
   for (let i = 0; i < process.argv.length; i += 1) {
     const value = process.argv[i + 1];
     if (process.argv[i] === flag && value && !value.startsWith("-")) {
-      values.push(process.argv[i + 1]);
+      values.push(value);
     }
   }
   return values;
@@ -483,7 +484,7 @@ function parseRepeatableFlag(flag: string): string[] {
 function validateCliArgs(argv: readonly string[] = process.argv.slice(2)): void {
   const seenSingleValueFlags = new Set<string>();
   for (let index = 0; index < argv.length; index += 1) {
-    const arg = argv[index];
+    const arg = expectDefined(argv[index], `CLI benchmark argument at index ${index}`);
     if (VALUE_FLAGS.has(arg)) {
       if (arg !== "--case") {
         if (seenSingleValueFlags.has(arg)) {
@@ -575,9 +576,13 @@ function median(values: number[]): number {
   const sorted = [...values].toSorted((a, b) => a - b);
   const mid = Math.floor(sorted.length / 2);
   if (sorted.length % 2 === 0) {
-    return (sorted[mid - 1] + sorted[mid]) / 2;
+    return (
+      (expectDefined(sorted[mid - 1], "lower middle CLI benchmark sample") +
+        expectDefined(sorted[mid], "upper middle CLI benchmark sample")) /
+      2
+    );
   }
-  return sorted[mid];
+  return expectDefined(sorted[mid], "middle CLI benchmark sample");
 }
 
 function percentile(values: number[], p: number): number {
diff --git a/scripts/bench-gateway-restart.ts b/scripts/bench-gateway-restart.ts
index 0354b2f401d..781b88b1a17 100644
--- a/scripts/bench-gateway-restart.ts
+++ b/scripts/bench-gateway-restart.ts
@@ -6,6 +6,7 @@ import { tmpdir } from "node:os";
 import path from "node:path";
 import { performance } from "node:perf_hooks";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { writeGatewayRestartIntentSync } from "../src/infra/restart.js";
 import { parseStrictIntegerOption } from "./lib/dev-tooling-safety.ts";
 import { delay, stopChild, type StopChildResult } from "./lib/gateway-bench-child.ts";
@@ -342,7 +343,7 @@ function resolveOutputPath(raw: string | undefined): string | undefined {
 
 function resolveCases(caseIds: string[]): GatewayBenchCase[] {
   if (caseIds.length === 0) {
-    return [GATEWAY_CASES[0]];
+    return [expectDefined(GATEWAY_CASES[0], "default gateway restart benchmark case")];
   }
   const seenIds = new Set<string>();
   const byId = new Map(GATEWAY_CASES.map((benchCase) => [benchCase.id, benchCase]));
@@ -412,7 +413,11 @@ function median(values: number[]): number {
   const sorted = [...values].toSorted((a, b) => a - b);
   const middle = Math.floor(sorted.length / 2);
   if (sorted.length % 2 === 0) {
-    return (sorted[middle - 1] + sorted[middle]) / 2;
+    return (
+      (expectDefined(sorted[middle - 1], "lower middle gateway restart sample") +
+        expectDefined(sorted[middle], "upper middle gateway restart sample")) /
+      2
+    );
   }
   return sorted[middle] ?? 0;
 }
@@ -510,8 +515,8 @@ function slope(values: Array<number | null>): number | null {
   if (points.length < 2) {
     return null;
   }
-  const first = points[0];
-  const last = points[points.length - 1];
+  const first = expectDefined(points[0], "first gateway restart slope point");
+  const last = expectDefined(points[points.length - 1], "last gateway restart slope point");
   const denominator = Math.max(1, last.index - first.index);
   return (last.value - first.value) / denominator;
 }
@@ -910,10 +915,11 @@ function collectTraceLine(
     "u",
   ).exec(line);
   if (phaseMatch) {
-    trace[phaseMatch[1]] = Number(phaseMatch[2]);
-    trace[`${phaseMatch[1]}.total`] = Number(phaseMatch[3]);
+    const phase = expectDefined(phaseMatch[1], `${prefix} phase name`);
+    trace[phase] = Number(expectDefined(phaseMatch[2], `${prefix} phase duration`));
+    trace[`${phase}.total`] = Number(expectDefined(phaseMatch[3], `${prefix} total duration`));
     for (const metric of parseTraceMetrics(phaseMatch[4] ?? "")) {
-      trace[`${phaseMatch[1]}.${metric.key}`] = metric.value;
+      trace[`${phase}.${metric.key}`] = metric.value;
     }
     return true;
   }
@@ -921,8 +927,10 @@ function collectTraceLine(
   if (!detailMatch) {
     return false;
   }
-  for (const metric of parseTraceMetrics(detailMatch[2])) {
-    trace[`${detailMatch[1]}.${metric.key}`] = metric.value;
+  const phase = expectDefined(detailMatch[1], `${prefix} detail phase name`);
+  const metrics = expectDefined(detailMatch[2], `${prefix} detail metrics`);
+  for (const metric of parseTraceMetrics(metrics)) {
+    trace[`${phase}.${metric.key}`] = metric.value;
   }
   return true;
 }
@@ -934,8 +942,8 @@ function parseTraceMetrics(raw: string): Array<{ key: string; value: number }> {
     if (!metricMatch) {
       continue;
     }
-    const key = metricMatch[1];
-    const value = Number(metricMatch[2]);
+    const key = expectDefined(metricMatch[1], "gateway restart trace metric key");
+    const value = Number(expectDefined(metricMatch[2], `gateway restart ${key} metric value`));
     if (!Number.isFinite(value)) {
       continue;
     }
diff --git a/scripts/bench-gateway-startup.ts b/scripts/bench-gateway-startup.ts
index 56fbea9fefe..89efc9f179c 100644
--- a/scripts/bench-gateway-startup.ts
+++ b/scripts/bench-gateway-startup.ts
@@ -5,6 +5,7 @@ import { tmpdir } from "node:os";
 import path from "node:path";
 import { performance } from "node:perf_hooks";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { parseStrictIntegerOption } from "./lib/dev-tooling-safety.ts";
 import { delay, stopChild } from "./lib/gateway-bench-child.ts";
 import {
@@ -351,7 +352,11 @@ function median(values: number[]): number {
   const sorted = [...values].toSorted((a, b) => a - b);
   const middle = Math.floor(sorted.length / 2);
   if (sorted.length % 2 === 0) {
-    return (sorted[middle - 1] + sorted[middle]) / 2;
+    return (
+      (expectDefined(sorted[middle - 1], "lower middle gateway startup sample") +
+        expectDefined(sorted[middle], "upper middle gateway startup sample")) /
+      2
+    );
   }
   return sorted[middle] ?? 0;
 }
@@ -694,10 +699,13 @@ function sanitizedEnv(
 function collectStartupTrace(line: string, startupTrace: Record<string, number>): void {
   const phaseMatch = /startup trace: ([^ ]+) ([0-9.]+)ms total=([0-9.]+)ms(?: (.*))?/u.exec(line);
   if (phaseMatch) {
-    startupTrace[phaseMatch[1]] = Number(phaseMatch[2]);
-    startupTrace[`${phaseMatch[1]}.total`] = Number(phaseMatch[3]);
+    const phase = expectDefined(phaseMatch[1], "gateway startup trace phase name");
+    startupTrace[phase] = Number(expectDefined(phaseMatch[2], `${phase} startup duration`));
+    startupTrace[`${phase}.total`] = Number(
+      expectDefined(phaseMatch[3], `${phase} total startup duration`),
+    );
     for (const metric of parseStartupTraceMetrics(phaseMatch[4] ?? "")) {
-      startupTrace[`${phaseMatch[1]}.${metric.key}`] = metric.value;
+      startupTrace[`${phase}.${metric.key}`] = metric.value;
     }
     return;
   }
@@ -705,8 +713,10 @@ function collectStartupTrace(line: string, startupTrace: Record<string, number>)
   if (!detailMatch) {
     return;
   }
-  for (const metric of parseStartupTraceMetrics(detailMatch[2])) {
-    startupTrace[`${detailMatch[1]}.${metric.key}`] = metric.value;
+  const phase = expectDefined(detailMatch[1], "gateway startup detail phase name");
+  const detail = expectDefined(detailMatch[2], `${phase} startup detail metrics`);
+  for (const metric of parseStartupTraceMetrics(detail)) {
+    startupTrace[`${phase}.${metric.key}`] = metric.value;
   }
 }
 
@@ -727,8 +737,8 @@ function parseStartupTraceMetrics(raw: string): Array<{ key: string; value: numb
     if (!metricMatch) {
       continue;
     }
-    const key = metricMatch[1];
-    const value = Number(metricMatch[2]);
+    const key = expectDefined(metricMatch[1], "gateway startup trace metric key");
+    const value = Number(expectDefined(metricMatch[2], `${key} startup trace metric value`));
     if (
       !Number.isFinite(value) ||
       (key !== "eventLoopMax" &&
diff --git a/scripts/bench-model.ts b/scripts/bench-model.ts
index a1d79e2cdf1..3809aa2e1e2 100644
--- a/scripts/bench-model.ts
+++ b/scripts/bench-model.ts
@@ -1,6 +1,7 @@
 // Bench Model script supports OpenClaw repository automation.
 import { pathToFileURL } from "node:url";
 import { completeSimple, type Model } from "openclaw/plugin-sdk/llm";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { parseStrictIntegerOption } from "./lib/dev-tooling-safety.ts";
 
 type Usage = {
@@ -111,9 +112,13 @@ function median(values: number[]): number {
   const sorted = [...values].toSorted((a, b) => a - b);
   const mid = Math.floor(sorted.length / 2);
   if (sorted.length % 2 === 0) {
-    return Math.round((sorted[mid - 1] + sorted[mid]) / 2);
+    return Math.round(
+      (expectDefined(sorted[mid - 1], "lower middle model benchmark sample") +
+        expectDefined(sorted[mid], "upper middle model benchmark sample")) /
+        2,
+    );
   }
-  return sorted[mid];
+  return expectDefined(sorted[mid], "middle model benchmark sample");
 }
 
 async function runModel(opts: {
diff --git a/scripts/bench-sqlite-state.ts b/scripts/bench-sqlite-state.ts
index 29361c34c53..1a7d1862f29 100644
--- a/scripts/bench-sqlite-state.ts
+++ b/scripts/bench-sqlite-state.ts
@@ -4,6 +4,7 @@ import os from "node:os";
 import path from "node:path";
 import type { DatabaseSync, SQLInputValue } from "node:sqlite";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import {
   openOpenClawAgentDatabase,
   closeOpenClawAgentDatabasesForTest,
@@ -459,7 +460,7 @@ function percentile(values: number[], pct: number): number {
   }
   const sorted = values.toSorted((left, right) => left - right);
   const index = Math.min(sorted.length - 1, Math.ceil((pct / 100) * sorted.length) - 1);
-  return Number(sorted[index].toFixed(3));
+  return Number(expectDefined(sorted[index], `SQLite benchmark percentile ${pct}`).toFixed(3));
 }
 
 function runTimedQuery(
diff --git a/scripts/check-temp-path-guardrails.ts b/scripts/check-temp-path-guardrails.ts
index 0750d403e6c..1d4f98e73a7 100644
--- a/scripts/check-temp-path-guardrails.ts
+++ b/scripts/check-temp-path-guardrails.ts
@@ -74,7 +74,7 @@ function findMatchingParen(source: string, openIndex: number): number {
   let depth = 1;
   const quoteState: QuoteScanState = { quote: null, escaped: false };
   for (let i = openIndex + 1; i < source.length; i += 1) {
-    const ch = source[i];
+    const ch = source.charAt(i);
     if (consumeQuotedChar(quoteState, ch)) {
       continue;
     }
@@ -192,7 +192,8 @@ function hasDynamicTmpdirJoin(source: string): boolean {
       if (closeParenIndex !== -1) {
         const argsSource = scanSource.slice(openParenIndex + 1, closeParenIndex);
         const args = splitTopLevelArguments(argsSource);
-        if (args.length >= 2 && isOsTmpdirExpression(args[0])) {
+        const firstArg = args[0];
+        if (firstArg && isOsTmpdirExpression(firstArg)) {
           for (const arg of args.slice(1)) {
             const trimmed = arg.trim();
             if (trimmed.startsWith("`") && trimmed.includes("${")) {
diff --git a/scripts/control-ui-i18n.ts b/scripts/control-ui-i18n.ts
index 80c42cbc00f..778a7f5ed36 100644
--- a/scripts/control-ui-i18n.ts
+++ b/scripts/control-ui-i18n.ts
@@ -7,6 +7,7 @@ import path from "node:path";
 import { fileURLToPath, pathToFileURL } from "node:url";
 import { completeSimple, type AssistantMessage, type Model } from "openclaw/plugin-sdk/llm";
 import * as ts from "typescript";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { formatErrorMessage } from "../src/infra/errors.ts";
 import {
   compareStringArrays,
@@ -1322,7 +1323,8 @@ function extractTranslationResult(message: AssistantMessage): string {
 function parseTranslationReply(raw: string): Record<string, unknown> {
   const trimmed = raw.trim();
   const fenced = /^```(?:json)?\s*\n([\s\S]*?)\n```\s*$/.exec(trimmed);
-  return JSON.parse(fenced ? fenced[1] : trimmed) as Record<string, unknown>;
+  const json = fenced ? expectDefined(fenced[1], "fenced translation JSON body") : trimmed;
+  return JSON.parse(json);
 }
 
 export function parseTranslationBatchReply(
diff --git a/scripts/control-ui-mock-dev.ts b/scripts/control-ui-mock-dev.ts
index c1d25e0cba6..f5c27816f40 100644
--- a/scripts/control-ui-mock-dev.ts
+++ b/scripts/control-ui-mock-dev.ts
@@ -4,6 +4,7 @@ import path from "node:path";
 import { fileURLToPath } from "node:url";
 import qrcode from "qrcode";
 import { createServer, type Plugin, type ViteDevServer } from "vite";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { CONTROL_UI_BOOTSTRAP_CONFIG_PATH } from "../src/gateway/control-ui-contract.js";
 import {
   createControlUiMockBootstrapConfig,
@@ -43,7 +44,7 @@ function mockFileHash(value: string): string {
 function parseArgs(args: string[]): CliOptions {
   const options: CliOptions = { allowedHosts: [], host: "127.0.0.1", port: 5187 };
   for (let i = 0; i < args.length; i += 1) {
-    const arg = args[i];
+    const arg = expectDefined(args[i], `control UI mock argument at index ${i}`);
     if (arg === "--allowed-host") {
       const allowedHost = args[++i]?.trim();
       if (allowedHost) {
diff --git a/scripts/debug-claude-usage.ts b/scripts/debug-claude-usage.ts
index a6a6f84975e..d31a213ea37 100644
--- a/scripts/debug-claude-usage.ts
+++ b/scripts/debug-claude-usage.ts
@@ -5,6 +5,7 @@ import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { normalizeOptionalString } from "../packages/normalization-core/src/string-coerce.js";
 import { readBoundedResponseText as readBoundedResponseTextWithLimit } from "./lib/bounded-response.ts";
 import {
@@ -44,7 +45,7 @@ const parseArgs = (args = process.argv.slice(2)): Args => {
   let sessionKey: string | undefined;
 
   for (let i = 0; i < args.length; i++) {
-    const arg = args[i];
+    const arg = expectDefined(args[i], `Claude usage argument at index ${i}`);
     if (arg === "--agent") {
       agentId = parseNonBlankArgValue(parseRequiredArgValue(args, i, "--agent"), "--agent");
       i += 1;
diff --git a/scripts/dev/discord-acp-plain-language-smoke.ts b/scripts/dev/discord-acp-plain-language-smoke.ts
index 9044324b2ff..24223f1567f 100644
--- a/scripts/dev/discord-acp-plain-language-smoke.ts
+++ b/scripts/dev/discord-acp-plain-language-smoke.ts
@@ -283,7 +283,7 @@ function validateCliArgs(argv: string[]): void {
       continue;
     }
     if (arg.startsWith("--") && arg.includes("=")) {
-      const [flag] = arg.split("=", 1);
+      const flag = arg.slice(0, arg.indexOf("="));
       if (VALUE_OPTIONS.has(flag)) {
         continue;
       }
diff --git a/scripts/e2e/lib/session-log-mentions.ts b/scripts/e2e/lib/session-log-mentions.ts
index bcb8c24af34..23512ad9f36 100644
--- a/scripts/e2e/lib/session-log-mentions.ts
+++ b/scripts/e2e/lib/session-log-mentions.ts
@@ -176,7 +176,7 @@ export async function countSessionLogMentions(params: {
         continue;
       }
       for (const [key, needle] of Object.entries(params.needles)) {
-        counts[key] += countOccurrences(scanText, needle);
+        counts[key] = (counts[key] ?? 0) + countOccurrences(scanText, needle);
       }
     }
   }
@@ -246,7 +246,7 @@ async function countSqliteTranscriptMentions(params: {
         continue;
       }
       for (const [key, needle] of Object.entries(params.needles)) {
-        counts[key] += countOccurrences(scanText, needle);
+        counts[key] = (counts[key] ?? 0) + countOccurrences(scanText, needle);
       }
     }
     return counts;
diff --git a/scripts/embedded-run-abort-leak.ts b/scripts/embedded-run-abort-leak.ts
index 76d3062cb0c..c534a8cf910 100644
--- a/scripts/embedded-run-abort-leak.ts
+++ b/scripts/embedded-run-abort-leak.ts
@@ -19,6 +19,7 @@
 import * as fs from "node:fs";
 import * as path from "node:path";
 import * as v8 from "node:v8";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 
 type Mode = "production" | "closure-extracted" | "closure-inline" | "synthetic-leak";
 type Abortable = <T>(signal: AbortSignal, promise: Promise<T>) => Promise<T>;
@@ -65,7 +66,7 @@ function parseArgs(argv: string[]): Options {
   };
   const seenValueFlags = new Set<string>();
   for (let i = 0; i < argv.length; i += 1) {
-    const arg = argv[i];
+    const arg = expectDefined(argv[i], `embedded abort benchmark argument at index ${i}`);
     const next = argv[i + 1];
     if (VALUE_FLAGS.has(arg)) {
       if (seenValueFlags.has(arg)) {
diff --git a/scripts/gh-read.ts b/scripts/gh-read.ts
index 6f774d91be1..060ccd23ed5 100644
--- a/scripts/gh-read.ts
+++ b/scripts/gh-read.ts
@@ -3,6 +3,7 @@ import { execFileSync, spawnSync } from "node:child_process";
 import { createPrivateKey, createSign } from "node:crypto";
 import { readFileSync } from "node:fs";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { readBoundedResponseText } from "./lib/bounded-response.ts";
 import { parseStrictIntegerOption } from "./lib/dev-tooling-safety.ts";
 
@@ -50,7 +51,7 @@ type GitHubBodyReadOptions = {
 
 export function parseRepoArg(args: string[]): string | null {
   for (let i = 0; i < args.length; i += 1) {
-    const arg = args[i];
+    const arg = expectDefined(args[i], `GitHub CLI argument at index ${i}`);
     if (arg === "-R" || arg === "--repo") {
       return normalizeRepo(args[i + 1] ?? null);
     }
diff --git a/scripts/lib/codex-app-server-protocol-source.ts b/scripts/lib/codex-app-server-protocol-source.ts
index b8883744e2f..1ef75aaf1f2 100644
--- a/scripts/lib/codex-app-server-protocol-source.ts
+++ b/scripts/lib/codex-app-server-protocol-source.ts
@@ -2,6 +2,7 @@
 import { spawnSync } from "node:child_process";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "../../packages/normalization-core/src/expect.js";
 import { resolvePnpmRunner } from "../pnpm-runner.mjs";
 import { stageCodexAppServerProtocolArtifacts } from "./codex-app-server-protocol-artifacts.js";
 
@@ -246,7 +247,7 @@ async function resolvePrimaryWorktreeSiblingCodex(repoRoot: string): Promise<str
     return undefined;
   }
 
-  const gitDir = path.resolve(repoRoot, match[1].trim());
+  const gitDir = path.resolve(repoRoot, expectDefined(match[1], "gitdir target").trim());
   const worktreeMarker = `${path.sep}.git${path.sep}worktrees${path.sep}`;
   const markerIndex = gitDir.indexOf(worktreeMarker);
   if (markerIndex < 0) {
diff --git a/scripts/lib/control-ui-i18n-sync-plan.ts b/scripts/lib/control-ui-i18n-sync-plan.ts
index ec4a0695afb..0e3a32f11d2 100644
--- a/scripts/lib/control-ui-i18n-sync-plan.ts
+++ b/scripts/lib/control-ui-i18n-sync-plan.ts
@@ -1,3 +1,5 @@
+import { expectDefined } from "../../packages/normalization-core/src/expect.js";
+
 export interface TranslationMap {
   [key: string]: string | TranslationMap;
 }
@@ -266,7 +268,7 @@ function setNestedValue(root: TranslationMap, dottedKey: string, value: string):
   const parts = dottedKey.split(".");
   let cursor: TranslationMap = root;
   for (let index = 0; index < parts.length - 1; index += 1) {
-    const key = parts[index];
+    const key = expectDefined(parts[index], `translation key segment at index ${index}`);
     const next = cursor[key];
     if (!next || typeof next === "string") {
       const replacement: TranslationMap = {};
@@ -276,7 +278,7 @@ function setNestedValue(root: TranslationMap, dottedKey: string, value: string):
     }
     cursor = next;
   }
-  cursor[parts.at(-1)!] = value;
+  cursor[expectDefined(parts.at(-1), "translation leaf key")] = value;
 }
 
 function renderTranslationValue(value: string | TranslationMap, indent = 0): string {
diff --git a/scripts/lib/gateway-bench-probes.ts b/scripts/lib/gateway-bench-probes.ts
index 37c709ae5a6..5fa7aa7962c 100644
--- a/scripts/lib/gateway-bench-probes.ts
+++ b/scripts/lib/gateway-bench-probes.ts
@@ -2,6 +2,7 @@
 import { spawnSync } from "node:child_process";
 import { request } from "node:http";
 import { createServer } from "node:net";
+import { expectDefined } from "../../packages/normalization-core/src/expect.js";
 
 export async function getFreePort(): Promise<number> {
   return new Promise((resolve, reject) => {
@@ -98,9 +99,9 @@ export function readProcessTreeCpuMs(rootPid: number | undefined): number | null
     if (!match) {
       continue;
     }
-    const pid = Number(match[1]);
-    const ppid = Number(match[2]);
-    const cpuMs = parsePsCpuTimeMs(match[3]);
+    const pid = Number(expectDefined(match[1], "process id from ps output"));
+    const ppid = Number(expectDefined(match[2], "parent process id from ps output"));
+    const cpuMs = parsePsCpuTimeMs(expectDefined(match[3], "CPU time from ps output"));
     if (!Number.isInteger(pid) || !Number.isInteger(ppid) || cpuMs === null) {
       continue;
     }
@@ -153,10 +154,21 @@ function parsePsCpuTimeMs(raw: string): number | null {
     return null;
   }
   if (parts.length === 2) {
-    return Math.round((parts[0] * 60 + parts[1]) * 1000);
+    const [minutes, seconds] = parts;
+    return Math.round(
+      (expectDefined(minutes, "process CPU minutes") * 60 +
+        expectDefined(seconds, "process CPU seconds")) *
+        1000,
+    );
   }
   if (parts.length === 3) {
-    return Math.round((parts[0] * 60 * 60 + parts[1] * 60 + parts[2]) * 1000);
+    const [hours, minutes, seconds] = parts;
+    return Math.round(
+      (expectDefined(hours, "process CPU hours") * 60 * 60 +
+        expectDefined(minutes, "process CPU minutes") * 60 +
+        expectDefined(seconds, "process CPU seconds")) *
+        1000,
+    );
   }
   return null;
 }
diff --git a/scripts/lib/plugin-npm-release.ts b/scripts/lib/plugin-npm-release.ts
index ae2773a6f99..053b9affe31 100644
--- a/scripts/lib/plugin-npm-release.ts
+++ b/scripts/lib/plugin-npm-release.ts
@@ -3,6 +3,7 @@ import { execFileSync } from "node:child_process";
 import { mkdtempSync, readdirSync, readFileSync, rmSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join, resolve } from "node:path";
+import { expectDefined } from "../../packages/normalization-core/src/expect.js";
 import { normalizeOptionalString } from "../../packages/normalization-core/src/string-coerce.js";
 import { validateExternalCodePluginPackageJson } from "../../packages/plugin-package-contract/src/index.ts";
 import {
@@ -259,7 +260,7 @@ export function parsePluginReleaseArgs(argv: string[]): ParsedPluginReleaseArgs
   let headRef: string | undefined;
 
   for (let index = 0; index < argv.length; index += 1) {
-    const arg = argv[index];
+    const arg = expectDefined(argv[index], `plugin release argument at index ${index}`);
     if (arg === "--") {
       continue;
     }
@@ -312,7 +313,7 @@ export function parsePluginNpmReleaseArgs(argv: string[]): ParsedPluginNpmReleas
   const baseArgs: string[] = [];
   let npmDistTag: "extended-stable" | undefined;
   for (let index = 0; index < argv.length; index += 1) {
-    const arg = argv[index];
+    const arg = expectDefined(argv[index], `plugin npm release argument at index ${index}`);
     if (arg !== "--npm-dist-tag") {
       baseArgs.push(arg);
       continue;
diff --git a/scripts/lib/sqlite-session-schema-baseline.ts b/scripts/lib/sqlite-session-schema-baseline.ts
index afb371ce7d6..b1fbed87151 100644
--- a/scripts/lib/sqlite-session-schema-baseline.ts
+++ b/scripts/lib/sqlite-session-schema-baseline.ts
@@ -2,6 +2,7 @@
 import { createHash } from "node:crypto";
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "../../packages/normalization-core/src/expect.js";
 
 /** Rendered baseline artifact for the sessions/transcripts SQLite schema. */
 export type SqliteSessionSchemaBaselineRender = {
@@ -62,14 +63,14 @@ function readCreatedTableName(statement: string): string | null {
   const match = statement.match(
     /^CREATE\s+TABLE\s+IF\s+NOT\s+EXISTS\s+("[^"]+"|[A-Za-z_][A-Za-z0-9_]*)\b/iu,
   );
-  return match ? normalizeIdentifier(match[1]) : null;
+  return match ? normalizeIdentifier(expectDefined(match[1], "created table name")) : null;
 }
 
 function readIndexedTableName(statement: string): string | null {
   const match = statement.match(
     /^CREATE\s+(?:UNIQUE\s+)?INDEX\s+IF\s+NOT\s+EXISTS\s+("[^"]+"|[A-Za-z_][A-Za-z0-9_]*)\s+ON\s+("[^"]+"|[A-Za-z_][A-Za-z0-9_]*)\b/isu,
   );
-  return match ? normalizeIdentifier(match[2]) : null;
+  return match ? normalizeIdentifier(expectDefined(match[2], "indexed table name")) : null;
 }
 
 function isTargetSessionSchemaStatement(statement: string): boolean {
diff --git a/scripts/lib/ts-topology/analyze.ts b/scripts/lib/ts-topology/analyze.ts
index 1279a84e139..350fc042ac0 100644
--- a/scripts/lib/ts-topology/analyze.ts
+++ b/scripts/lib/ts-topology/analyze.ts
@@ -1,6 +1,7 @@
 // Analyze script supports OpenClaw repository automation.
 import path from "node:path";
 import ts from "typescript";
+import { expectDefined } from "../../../packages/normalization-core/src/expect.js";
 import {
   canonicalSymbolInfo,
   countIdentifierUsages,
@@ -298,8 +299,12 @@ function finalizeRecords(records: TopologyRecord[]) {
       return byRefs;
     }
     return (
-      left.publicSpecifiers[0].localeCompare(right.publicSpecifiers[0]) ||
-      left.exportNames[0].localeCompare(right.exportNames[0])
+      expectDefined(left.publicSpecifiers[0], "left topology public specifier").localeCompare(
+        expectDefined(right.publicSpecifiers[0], "right topology public specifier"),
+      ) ||
+      expectDefined(left.exportNames[0], "left topology export name").localeCompare(
+        expectDefined(right.exportNames[0], "right topology export name"),
+      )
     );
   });
 }
diff --git a/scripts/native-app-i18n.ts b/scripts/native-app-i18n.ts
index 27eb080b394..28f0b1c1014 100644
--- a/scripts/native-app-i18n.ts
+++ b/scripts/native-app-i18n.ts
@@ -2,6 +2,7 @@ import { createHash } from "node:crypto";
 import { mkdir, readdir, readFile, writeFile } from "node:fs/promises";
 import path from "node:path";
 import { fileURLToPath, pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { translateNativeEntries } from "./control-ui-i18n.ts";
 
 type NativeI18nSurface = "android" | "apple";
@@ -211,18 +212,18 @@ function isAsciiAlphaNumeric(character: string): boolean {
 
 export function isConditionalBranchIdentifier(source: string): boolean {
   let index = 0;
-  while (index < source.length && isAsciiLowercaseLetter(source[index])) {
+  while (index < source.length && isAsciiLowercaseLetter(source.charAt(index))) {
     index += 1;
   }
 
   // Keep this scanner linear: PR-controlled native source passes through CI,
   // so a backtracking regex here can become a cheap native-i18n DoS trigger.
-  if (index === 0 || index >= source.length || !isAsciiUppercaseLetter(source[index])) {
+  if (index === 0 || index >= source.length || !isAsciiUppercaseLetter(source.charAt(index))) {
     return false;
   }
 
   for (index += 1; index < source.length; index += 1) {
-    if (!isAsciiAlphaNumeric(source[index])) {
+    if (!isAsciiAlphaNumeric(source.charAt(index))) {
       return false;
     }
   }
@@ -622,15 +623,18 @@ function identifierBefore(source: string, offset: number): string | null {
     cursor -= 1;
   }
   const end = cursor + 1;
-  while (cursor >= 0 && (isAsciiAlphaNumeric(source[cursor]) || source[cursor] === "_")) {
+  while (
+    cursor >= 0 &&
+    (isAsciiAlphaNumeric(source.charAt(cursor)) || source.charAt(cursor) === "_")
+  ) {
     cursor -= 1;
   }
   const start = cursor + 1;
   if (
     start === end ||
-    (!isAsciiLowercaseLetter(source[start]) &&
-      !isAsciiUppercaseLetter(source[start]) &&
-      source[start] !== "_")
+    (!isAsciiLowercaseLetter(source.charAt(start)) &&
+      !isAsciiUppercaseLetter(source.charAt(start)) &&
+      source.charAt(start) !== "_")
   ) {
     return null;
   }
@@ -739,18 +743,18 @@ function addCapturedLiteralCandidates(
 
 function skipWhitespaceAndBrace(source: string, offset: number): number {
   let cursor = offset;
-  while (cursor < source.length && /\s/u.test(source[cursor])) {
+  while (cursor < source.length && /\s/u.test(source.charAt(cursor))) {
     cursor += 1;
   }
-  if (source[cursor] === "{") {
+  if (source.charAt(cursor) === "{") {
     cursor += 1;
-    while (cursor < source.length && /\s/u.test(source[cursor])) {
+    while (cursor < source.length && /\s/u.test(source.charAt(cursor))) {
       cursor += 1;
     }
   }
   if (source.startsWith("return", cursor) && !isAsciiAlphaNumeric(source[cursor + 6] ?? "")) {
     cursor += 6;
-    while (cursor < source.length && /\s/u.test(source[cursor])) {
+    while (cursor < source.length && /\s/u.test(source.charAt(cursor))) {
       cursor += 1;
     }
   }
@@ -1189,7 +1193,9 @@ async function mapWithConcurrency<T, R>(
         if (index >= values.length) {
           return;
         }
-        results[index] = await run(values[index]);
+        results[index] = await run(
+          expectDefined(values[index], `native i18n concurrency input at index ${index}`),
+        );
       }
     }),
   );
@@ -1306,10 +1312,14 @@ function adjacentDuplicateWords(value: string, locale: string): string[] {
   const duplicates = new Set<string>();
   for (let index = 1; index < words.length; index += 1) {
     if (
-      words[index - 1].normalize("NFKC").toLocaleLowerCase(locale) ===
-      words[index].normalize("NFKC").toLocaleLowerCase(locale)
+      expectDefined(words[index - 1], `native i18n word before index ${index}`)
+        .normalize("NFKC")
+        .toLocaleLowerCase(locale) ===
+      expectDefined(words[index], `native i18n word at index ${index}`)
+        .normalize("NFKC")
+        .toLocaleLowerCase(locale)
     ) {
-      duplicates.add(words[index]);
+      duplicates.add(expectDefined(words[index], `duplicate native i18n word at index ${index}`));
     }
   }
   return [...duplicates].toSorted(compareCodePoints);
@@ -1443,8 +1453,8 @@ export function validateNativeLocaleArtifact(
     errors.push(`entry count must be ${inventory.length}, got ${rawEntries.length}`);
   }
   for (let index = 0; index < Math.min(entries.length, inventory.length); index += 1) {
-    const actual = entries[index];
-    const expected = inventory[index];
+    const actual = expectDefined(entries[index], `native locale entry at index ${index}`);
+    const expected = expectDefined(inventory[index], `native inventory entry at index ${index}`);
     if (actual.id !== expected.id) {
       errors.push(
         `entries[${index}].id must be ${JSON.stringify(expected.id)}, got ${JSON.stringify(actual.id)}`,
diff --git a/scripts/openclaw-cross-os-release-checks.ts b/scripts/openclaw-cross-os-release-checks.ts
index f79687b06ab..201c64e43b6 100644
--- a/scripts/openclaw-cross-os-release-checks.ts
+++ b/scripts/openclaw-cross-os-release-checks.ts
@@ -349,6 +349,9 @@ export function parseArgs(argv: string[]): ParsedArgs {
   const parsed: ParsedArgs = {};
   for (let index = 0; index < argv.length; index += 1) {
     const token = argv[index];
+    if (token === undefined) {
+      throw new Error(`Missing cross-OS release argument at index ${index}`);
+    }
     if (!token.startsWith("--")) {
       continue;
     }
@@ -4081,16 +4084,16 @@ function parseAgentPayloadTexts(stdout: string) {
       : Array.isArray(payload?.result?.payloads)
         ? payload.result.payloads
         : [];
-    const payloadTexts = Array.isArray(entries)
-      ? entries.flatMap((entry) => (typeof entry?.text === "string" ? [entry.text] : []))
-      : [];
+    const payloadTexts = entries.flatMap((entry) =>
+      typeof entry?.text === "string" ? [entry.text] : [],
+    );
     return [...directTexts, ...payloadTexts];
   } catch {
     const finalTextMatches = [
       ...stdout.matchAll(
         /"(?:finalAssistantVisibleText|finalAssistantRawText|text)"\s*:\s*"([^"]*)"/gu,
       ),
-    ].map((match) => match[1]);
+    ].flatMap((match) => (match[1] === undefined ? [] : [match[1]]));
     return finalTextMatches.length > 0 ? finalTextMatches : stdout.trim() ? [stdout] : [];
   }
 }
diff --git a/scripts/openclaw-npm-postpublish-verify.ts b/scripts/openclaw-npm-postpublish-verify.ts
index 097fcdbffe0..59b46f3b507 100644
--- a/scripts/openclaw-npm-postpublish-verify.ts
+++ b/scripts/openclaw-npm-postpublish-verify.ts
@@ -24,6 +24,7 @@ import {
   win32 as pathWin32,
 } from "node:path";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { formatErrorMessage } from "../src/infra/errors.ts";
 import { ALWAYS_ALLOWED_RUNTIME_DIR_NAMES } from "../src/plugin-sdk/facade-activation-contract.ts";
 import { BUNDLED_RUNTIME_SIDECAR_PATHS } from "../src/plugins/runtime-sidecar-paths.ts";
@@ -459,7 +460,10 @@ export function collectInstalledBundledRuntimeSidecarPaths(packageRoot: string):
   const installedExtensionIds = collectInstalledBundledExtensionIds(packageRoot);
   return PUBLISHED_BUNDLED_RUNTIME_SIDECAR_PATHS.filter((relativePath) => {
     const match = /^dist\/extensions\/([^/]+)\//u.exec(relativePath);
-    return match !== null && installedExtensionIds.has(match[1]);
+    return (
+      match !== null &&
+      installedExtensionIds.has(expectDefined(match[1], "bundled runtime extension id"))
+    );
   });
 }
 
@@ -896,7 +900,7 @@ function collectExpectedBundledExtensionPackageIds(): ReadonlySet<string> {
   for (const relativePath of listBundledPluginPackArtifacts()) {
     const match = /^dist\/extensions\/([^/]+)\/package\.json$/u.exec(relativePath);
     if (match) {
-      ids.add(match[1]);
+      ids.add(expectDefined(match[1], "bundled package extension id"));
     }
   }
   return ids;
diff --git a/scripts/openclaw-npm-prepublish-verify.ts b/scripts/openclaw-npm-prepublish-verify.ts
index 09d05d0ffcd..9ef88ae8383 100644
--- a/scripts/openclaw-npm-prepublish-verify.ts
+++ b/scripts/openclaw-npm-prepublish-verify.ts
@@ -5,6 +5,7 @@ import { mkdirSync, mkdtempSync, readFileSync, realpathSync, rmSync, writeFileSy
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { formatErrorMessage } from "../src/infra/errors.ts";
 import { type NpmVerifyCommandInvocation, runNpmVerifyCommand } from "./lib/npm-verify-exec.ts";
 import { runInstalledWorkspaceBootstrapSmoke } from "./lib/workspace-bootstrap-smoke.mjs";
@@ -105,7 +106,11 @@ function main(argv = process.argv.slice(2)): void {
           {
             private: true,
             dependencies: {
-              "@openclaw/ai": pathToFileURL(realpathSync(args.dependencyTarballPaths[0])).href,
+              "@openclaw/ai": pathToFileURL(
+                realpathSync(
+                  expectDefined(args.dependencyTarballPaths[0], "prepared dependency tarball"),
+                ),
+              ).href,
               openclaw: pathToFileURL(realpathSync(args.tarballPath)).href,
             },
           },
diff --git a/scripts/openclaw-npm-release-check.ts b/scripts/openclaw-npm-release-check.ts
index 4b670446cd7..deede407d8f 100644
--- a/scripts/openclaw-npm-release-check.ts
+++ b/scripts/openclaw-npm-release-check.ts
@@ -163,7 +163,7 @@ function isNodeModulesPackageRoot(segments: string[], index: number): boolean {
   if (parent === "node_modules") {
     return true;
   }
-  return parent?.startsWith("@") && segments[index - 2] === "node_modules";
+  return parent !== undefined && parent.startsWith("@") && segments[index - 2] === "node_modules";
 }
 
 function pathContainsPackedTestCargo(packedPath: string): boolean {
diff --git a/scripts/prepare-codex-ci-config.ts b/scripts/prepare-codex-ci-config.ts
index 3eaac1bd66a..c2412da4c73 100644
--- a/scripts/prepare-codex-ci-config.ts
+++ b/scripts/prepare-codex-ci-config.ts
@@ -1,6 +1,7 @@
 // Prepare Codex Ci Config script supports OpenClaw repository automation.
 import fs from "node:fs/promises";
 import path from "node:path";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 
 function tomlString(value: string): string {
   return JSON.stringify(value);
@@ -50,7 +51,7 @@ export async function writeCiSafeCodexConfig(params: {
 }
 
 if (path.basename(process.argv[1] ?? "") === "prepare-codex-ci-config.ts") {
-  const outputPath = process.argv[2];
+  const outputPath = expectDefined(process.argv[2], "Codex CI config output path");
   const projectPath = process.argv[3] ?? process.cwd();
   await writeCiSafeCodexConfig({ outputPath, projectPath });
 }
diff --git a/scripts/protocol-gen-swift.ts b/scripts/protocol-gen-swift.ts
index 6f1d3049280..11d7a92821a 100644
--- a/scripts/protocol-gen-swift.ts
+++ b/scripts/protocol-gen-swift.ts
@@ -84,7 +84,7 @@ function camelCase(input: string) {
     .trim()
     .toLowerCase()
     .split(/\s+/)
-    .map((p, i) => (i === 0 ? p : p[0].toUpperCase() + p.slice(1)))
+    .map((p, i) => (i === 0 ? p : p.charAt(0).toUpperCase() + p.slice(1)))
     .join("");
 }
 
diff --git a/scripts/qa-e2e.ts b/scripts/qa-e2e.ts
index 41e5240e2b0..3cc2b763241 100644
--- a/scripts/qa-e2e.ts
+++ b/scripts/qa-e2e.ts
@@ -118,7 +118,7 @@ export async function main(
 
 function isMainModule() {
   const entry = process.argv[1];
-  return Boolean(entry) && import.meta.url === pathToFileURL(entry).href;
+  return entry !== undefined && import.meta.url === pathToFileURL(entry).href;
 }
 
 if (isMainModule()) {
diff --git a/scripts/qa/render-maturity-docs.ts b/scripts/qa/render-maturity-docs.ts
index b4f7eca7a50..1a1ad292f86 100644
--- a/scripts/qa/render-maturity-docs.ts
+++ b/scripts/qa/render-maturity-docs.ts
@@ -841,7 +841,7 @@ function copyStaticSourceAssets({
   taxonomyPath: string;
 }): string[] {
   fs.mkdirSync(staticAssetsDir, { recursive: true });
-  const copied = [
+  const copied: Array<[string, string]> = [
     [taxonomyPath, path.join(staticAssetsDir, "taxonomy.yaml")],
     [scoresPath, path.join(staticAssetsDir, "maturity-scores.yaml")],
   ];
diff --git a/scripts/release-check.ts b/scripts/release-check.ts
index 84baf2a1bee..51cc8314e9c 100755
--- a/scripts/release-check.ts
+++ b/scripts/release-check.ts
@@ -18,6 +18,7 @@ import type { Dirent } from "node:fs";
 import { tmpdir } from "node:os";
 import { basename, dirname, join, resolve, win32 } from "node:path";
 import { pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { COMPLETION_SKIP_PLUGIN_COMMANDS_ENV } from "../src/cli/completion-runtime.ts";
 import {
   isLegacyPluginDependencyInstallStagePath,
@@ -89,7 +90,12 @@ const requiredPathGroups = [
   ...listBundledPluginPackArtifacts(),
   ...listStaticExtensionAssetOutputs().filter((relativePath) => {
     const match = /^dist\/extensions\/([^/]+)\//u.exec(relativePath);
-    return !match || !rootPackageExcludedExtensionDirs.has(match[1]);
+    return (
+      !match ||
+      !rootPackageExcludedExtensionDirs.has(
+        expectDefined(match[1], "release-check extension artifact id"),
+      )
+    );
   }),
   ...WORKSPACE_TEMPLATE_PACK_PATHS,
   "scripts/npm-runner.mjs",
@@ -422,7 +428,7 @@ export function resolvePackedTarballPath(packDestination: string, results: PackR
       `release-check: npm pack produced ${filenames.length} tarballs; expected exactly one.`,
     );
   }
-  const filename = filenames[0];
+  const filename = expectDefined(filenames[0], "npm pack tarball filename");
   const filenameBasename = basename(filename);
   const resolvedDestination = resolve(packDestination);
   const resolvedTarball = resolve(resolvedDestination, filenameBasename);
@@ -1112,7 +1118,8 @@ export function collectAppcastSparkleVersionErrors(xml: string): string[] {
     errors.push("appcast.xml contains no <item> entries.");
   }
 
-  for (const [, item] of itemMatches) {
+  for (const [index, match] of itemMatches.entries()) {
+    const item = expectDefined(match[1], `appcast item body at index ${index}`);
     const title = extractTag(item, "title") ?? "unknown";
     const shortVersion = extractTag(item, "sparkle:shortVersionString");
     const sparkleVersion = extractTag(item, "sparkle:version");
diff --git a/scripts/release-version.ts b/scripts/release-version.ts
index 8eea9213699..5b1c9af3092 100644
--- a/scripts/release-version.ts
+++ b/scripts/release-version.ts
@@ -1,6 +1,7 @@
 // Release Version keeps the core and explicitly selected native release trains aligned.
 import fs from "node:fs";
 import path from "node:path";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import {
   canonicalAndroidVersionCode,
   normalizeAndroidVersionCode,
@@ -131,7 +132,10 @@ export function applyReleaseVersionPlan(plan: ReleaseVersionPlan): void {
       tempPaths.push(tempPath);
     }
     for (const [index, change] of plan.changes.entries()) {
-      fs.renameSync(tempPaths[index], change.path);
+      fs.renameSync(
+        expectDefined(tempPaths[index], `release temp path at index ${index}`),
+        change.path,
+      );
     }
   } finally {
     for (const tempPath of tempPaths) {
diff --git a/scripts/sync-labels.ts b/scripts/sync-labels.ts
index 4a574fadb8a..968429c8122 100644
--- a/scripts/sync-labels.ts
+++ b/scripts/sync-labels.ts
@@ -109,7 +109,7 @@ function resolveLabelMetadata(label: string): { color: string; description?: str
   if (extraMetadata) {
     return extraMetadata;
   }
-  const prefix = label.includes(":") ? label.split(":", 1)[0].trim() : label.trim();
+  const prefix = label.includes(":") ? label.slice(0, label.indexOf(":")).trim() : label.trim();
   return { color: COLOR_BY_PREFIX.get(prefix) ?? "ededed" };
 }
 
diff --git a/scripts/test-shell-completion.ts b/scripts/test-shell-completion.ts
index d229dd52848..680119ea093 100644
--- a/scripts/test-shell-completion.ts
+++ b/scripts/test-shell-completion.ts
@@ -27,6 +27,7 @@ import os from "node:os";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
 import { confirm, isCancel } from "@clack/prompts";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { stylePromptMessage } from "../packages/terminal-core/src/prompt-style.js";
 import { theme } from "../packages/terminal-core/src/theme.js";
 import {
@@ -58,7 +59,7 @@ function parseArgs(args: string[]): Options {
   };
 
   for (let index = 0; index < args.length; index += 1) {
-    const arg = args[index];
+    const arg = expectDefined(args[index], `shell completion argument at index ${index}`);
     if (arg === "--check-only") {
       options.checkOnly = true;
     } else if (arg === "--force") {
diff --git a/scripts/ts-topology.ts b/scripts/ts-topology.ts
index 87e9d208003..47968ec2fc1 100644
--- a/scripts/ts-topology.ts
+++ b/scripts/ts-topology.ts
@@ -1,6 +1,7 @@
 #!/usr/bin/env node
 // Ts Topology script supports OpenClaw repository automation.
 import path from "node:path";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import { formatErrorMessage } from "../src/infra/errors.ts";
 import { parsePositiveInt } from "./lib/numeric-options.mjs";
 import { analyzeTopology } from "./lib/ts-topology/analyze.js";
@@ -88,7 +89,7 @@ function parseArgs(argv: string[]): CliOptions {
         options.report = (value as TopologyReportName | undefined) ?? options.report;
         break;
       case "--limit":
-        options.limit = parsePositiveInt(value, "--limit");
+        options.limit = parsePositiveInt(expectDefined(value, "--limit value"), "--limit");
         break;
       case "--repo-root":
         options.repoRoot = path.resolve(value ?? options.repoRoot);
diff --git a/scripts/update-clawtributors.ts b/scripts/update-clawtributors.ts
index fc7c6aede3e..e8392e5cc1a 100644
--- a/scripts/update-clawtributors.ts
+++ b/scripts/update-clawtributors.ts
@@ -2,6 +2,7 @@
 import { execFileSync, execSync } from "node:child_process";
 import { readFileSync, writeFileSync } from "node:fs";
 import { resolve } from "node:path";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import type { ApiContributor, Entry, MapConfig, User } from "./update-clawtributors.types.js";
 
 const REPO = "openclaw/openclaw";
@@ -99,13 +100,13 @@ for (const line of log.split("\n")) {
   }
 
   // Skip docs paths so bulk-generated i18n scaffolds don't inflate rankings
-  const filePath = parts[2];
+  const filePath = expectDefined(parts[2], "git numstat file path");
   if (filePath.startsWith("docs/")) {
     continue;
   }
 
-  const adds = parseCount(parts[0]);
-  const dels = parseCount(parts[1]);
+  const adds = parseCount(expectDefined(parts[0], "git numstat additions"));
+  const dels = parseCount(expectDefined(parts[1], "git numstat deletions"));
   const total = adds + dels;
   if (!total) {
     continue;
@@ -649,7 +650,10 @@ async function mapConcurrent<T, R>(
   const workers = Array.from({ length: Math.max(1, Math.min(limit, items.length)) }, async () => {
     while (nextIndex < items.length) {
       const index = nextIndex++;
-      results[index] = await mapper(items[index], index);
+      results[index] = await mapper(
+        expectDefined(items[index], `clawtributor concurrency input at index ${index}`),
+        index,
+      );
     }
   });
   await Promise.all(workers);
@@ -702,7 +706,7 @@ function readJpegDimensions(buffer: Buffer): { width: number; height: number } |
       continue;
     }
 
-    const marker = buffer[offset + 1];
+    const marker = expectDefined(buffer[offset + 1], `JPEG marker at byte ${offset + 1}`);
     offset += 2;
 
     if (marker === 0xd8 || marker === 0xd9) {
@@ -759,13 +763,15 @@ function resolveLogin(
   }
 
   if (email && email.endsWith("@users.noreply.github.com")) {
-    const local = email.split("@", 1)[0];
-    const login = local.includes("+") ? local.split("+")[1] : local;
+    const local = expectDefined(email.split("@", 1)[0], "GitHub noreply email local part");
+    const login = local.includes("+")
+      ? expectDefined(local.split("+")[1], "GitHub noreply email login suffix")
+      : local;
     return normalizeLogin(login);
   }
 
   if (email && email.endsWith("@github.com")) {
-    const login = email.split("@", 1)[0];
+    const login = expectDefined(email.split("@", 1)[0], "GitHub email local part");
     if (apiByLoginValue.has(login.toLowerCase())) {
       return normalizeLogin(login);
     }
diff --git a/scripts/write-cli-startup-metadata.ts b/scripts/write-cli-startup-metadata.ts
index 2bfd7f3606b..871676d8966 100644
--- a/scripts/write-cli-startup-metadata.ts
+++ b/scripts/write-cli-startup-metadata.ts
@@ -4,6 +4,7 @@ import { createHash } from "node:crypto";
 import { existsSync, mkdirSync, readdirSync, readFileSync, writeFileSync } from "node:fs";
 import path from "node:path";
 import { fileURLToPath, pathToFileURL } from "node:url";
+import { expectDefined } from "../packages/normalization-core/src/expect.js";
 import type { RootHelpRenderOptions } from "../src/cli/program/root-help.js";
 import type { OpenClawConfig } from "../src/config/config.js";
 import { resolveWindowsTaskkillPath } from "./lib/windows-taskkill.mjs";
@@ -364,7 +365,9 @@ async function mapWithConcurrency<T, R>(
         if (index >= values.length) {
           return;
         }
-        results[index] = await run(values[index]);
+        results[index] = await run(
+          expectDefined(values[index], `CLI metadata concurrency input at index ${index}`),
+        );
       }
     }),
   );
diff --git a/tsconfig.scripts.json b/tsconfig.scripts.json
index c253fa9a762..2639e794702 100644
--- a/tsconfig.scripts.json
+++ b/tsconfig.scripts.json
@@ -1,6 +1,7 @@
 {
   "extends": "./tsconfig.json",
   "compilerOptions": {
+    "noUncheckedIndexedAccess": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "tsBuildInfoFile": ".artifacts/tsgo-cache/scripts.tsbuildinfo"