diff --git a/extensions/google-meet/src/cli.test.ts b/extensions/google-meet/src/cli.test.ts
index 5a638aecce07..d8097255b081 100644
--- a/extensions/google-meet/src/cli.test.ts
+++ b/extensions/google-meet/src/cli.test.ts
@@ -832,6 +832,50 @@ describe("google-meet CLI", () => {
     }
   });
 
+  it.each([
+    ["0", 0],
+    ["3", 3],
+    ["+3", 3],
+    [" 3 ", 3],
+    [String(Number.MAX_SAFE_INTEGER), Number.MAX_SAFE_INTEGER],
+  ] as const)("accepts base-10 safe transcript cursors: %s", async (since, expected) => {
+    const callGatewayFromCli = vi.fn(async () => ({
+      found: true,
+      sessionId: "meet_gateway",
+      startIndex: expected,
+      nextIndex: expected,
+      lines: [],
+    }));
+
+    await setupCli({ callGatewayFromCli }).parseAsync(
+      ["googlemeet", "transcript", "meet_gateway", "--since", since],
+      { from: "user" },
+    );
+
+    expect(callGatewayFromCli).toHaveBeenCalledWith(
+      "googlemeet.transcript",
+      { json: true, timeout: "5000" },
+      { sessionId: "meet_gateway", sinceIndex: expected },
+      { progress: false },
+    );
+  });
+
+  it.each(["", " ", "-1", "0x10", "0o10", "0b10", "1e0", "1.5", "9007199254740992"])(
+    "rejects non-decimal transcript cursors before gateway delegation: %s",
+    async (since) => {
+      const callGatewayFromCli = vi.fn();
+
+      await expect(
+        setupCli({ callGatewayFromCli }).parseAsync(
+          ["googlemeet", "transcript", "meet_gateway", "--since", since],
+          { from: "user" },
+        ),
+      ).rejects.toThrow("--since must be a non-negative safe integer");
+
+      expect(callGatewayFromCli).not.toHaveBeenCalled();
+    },
+  );
+
   it("delegates join to the gateway-owned runtime when available", async () => {
     const callGatewayFromCli = vi.fn(async () => ({
       session: {
diff --git a/extensions/google-meet/src/cli.ts b/extensions/google-meet/src/cli.ts
index efac5d9499e0..1f5a091aceee 100644
--- a/extensions/google-meet/src/cli.ts
+++ b/extensions/google-meet/src/cli.ts
@@ -1,4 +1,3 @@
-// Google Meet plugin module implements cli behavior.
 import { mkdir, writeFile } from "node:fs/promises";
 import path from "node:path";
 import { createInterface } from "node:readline/promises";
@@ -9,6 +8,7 @@ import { expectDefined } from "openclaw/plugin-sdk/expect-runtime";
 import { callGatewayFromCli } from "openclaw/plugin-sdk/gateway-runtime";
 import {
   clampTimerTimeoutMs,
+  parseStrictNonNegativeInteger,
   parseStrictPositiveInteger,
 } from "openclaw/plugin-sdk/number-runtime";
 import prettyMilliseconds from "pretty-ms";
@@ -2263,8 +2263,8 @@ export function registerGoogleMeetCli(params: {
     .option("--since <index>", "Resume from the previous response's nextIndex")
     .option("--json", "Print JSON output", false)
     .action(async (sessionId: string, options: { since?: string; json?: boolean }) => {
-      const sinceIndex = options.since === undefined ? undefined : Number(options.since);
-      if (sinceIndex !== undefined && (!Number.isSafeInteger(sinceIndex) || sinceIndex < 0)) {
+      const sinceIndex = parseStrictNonNegativeInteger(options.since);
+      if (options.since !== undefined && sinceIndex === undefined) {
         throw new Error("--since must be a non-negative safe integer");
       }
       const delegated = await callGoogleMeetGateway({