diff --git a/gitnexus/src/cli/wiki.ts b/gitnexus/src/cli/wiki.ts
index 84aeb87bf..ef968b6fa 100644
--- a/gitnexus/src/cli/wiki.ts
+++ b/gitnexus/src/cli/wiki.ts
@@ -37,13 +37,21 @@ export interface WikiCommandOptions {
   retries?: string;
 }
 
-function parsePositiveIntegerOption(value: string | undefined, flag: string): number | undefined {
+function parsePositiveIntegerOption(
+  value: string | undefined,
+  flag: string,
+  multiplier = 1,
+): number | undefined {
   if (value === undefined) return undefined;
   const trimmed = value.trim();
   if (!/^[1-9]\d*$/.test(trimmed)) {
     throw new Error(`${flag} must be a positive integer`);
   }
-  return parseInt(trimmed, 10);
+  const parsed = parseInt(trimmed, 10);
+  if (parsed > Math.floor(Number.MAX_SAFE_INTEGER / multiplier)) {
+    throw new Error(`${flag} is too large`);
+  }
+  return parsed;
 }
 
 /**
@@ -138,7 +146,7 @@ export const wikiCommand = async (inputPath?: string, options?: WikiCommandOptio
 
   let timeoutSeconds: number | undefined;
   try {
-    timeoutSeconds = parsePositiveIntegerOption(options?.timeout, '--timeout');
+    timeoutSeconds = parsePositiveIntegerOption(options?.timeout, '--timeout', 1000);
   } catch (error) {
     console.log(`  Error: ${(error as Error).message}\n`);
     process.exitCode = 1;
diff --git a/gitnexus/test/unit/wiki-flags.test.ts b/gitnexus/test/unit/wiki-flags.test.ts
index 780b475c0..ff4b5eaa0 100644
--- a/gitnexus/test/unit/wiki-flags.test.ts
+++ b/gitnexus/test/unit/wiki-flags.test.ts
@@ -266,6 +266,7 @@ describe('WikiGenerator --review mode', () => {
 
 describe('wikiCommand --timeout validation', () => {
   const originalExitCode = process.exitCode;
+  const tooLargeTimeout = String(Math.floor(Number.MAX_SAFE_INTEGER / 1000) + 1);
 
   beforeEach(() => {
     vi.resetModules();
@@ -282,7 +283,7 @@ describe('wikiCommand --timeout validation', () => {
     process.exitCode = originalExitCode;
   });
 
-  it.each(['', '   ', '0', '-1', 'abc', '3.14'])(
+  it.each(['', '   ', '0', '-1', 'abc', '3.14', tooLargeTimeout])(
     'rejects invalid --timeout value %s before starting generation',
     async (timeout) => {
       const generatorCtor = vi.fn().mockImplementation(() => ({
@@ -343,7 +344,11 @@ describe('wikiCommand --timeout validation', () => {
 
       expect(process.exitCode).toBe(1);
       expect(generatorCtor).not.toHaveBeenCalled();
-      expect(consoleSpy).toHaveBeenCalledWith('  Error: --timeout must be a positive integer\n');
+      const expectedMessage =
+        timeout === tooLargeTimeout
+          ? '  Error: --timeout is too large\n'
+          : '  Error: --timeout must be a positive integer\n';
+      expect(consoleSpy).toHaveBeenCalledWith(expectedMessage);
     },
   );
 });