diff --git a/extensions/matrix/src/matrix/actions/limits.ts b/extensions/matrix/src/matrix/actions/limits.ts
index f18d9e2c059..7a6512eba39 100644
--- a/extensions/matrix/src/matrix/actions/limits.ts
+++ b/extensions/matrix/src/matrix/actions/limits.ts
@@ -1,6 +1,5 @@
+import { resolveIntegerOption } from "openclaw/plugin-sdk/number-runtime";
+
 export function resolveMatrixActionLimit(raw: unknown, fallback: number): number {
-  if (typeof raw !== "number" || !Number.isFinite(raw)) {
-    return fallback;
-  }
-  return Math.max(1, Math.floor(raw));
+  return resolveIntegerOption(raw, fallback, { min: 1 });
 }
diff --git a/extensions/matrix/src/matrix/client/config.test.ts b/extensions/matrix/src/matrix/client/config.test.ts
index b803bab0f94..37d21ee21f7 100644
--- a/extensions/matrix/src/matrix/client/config.test.ts
+++ b/extensions/matrix/src/matrix/client/config.test.ts
@@ -85,6 +85,24 @@ describe("Matrix auth/config live surfaces", () => {
     expect(resolved.encryption).toBe(false);
   });
 
+  it("ignores non-finite initial sync limits", () => {
+    const cfg = {
+      channels: {
+        matrix: {
+          initialSyncLimit: Number.NaN,
+          accounts: {
+            ops: {
+              initialSyncLimit: Number.POSITIVE_INFINITY,
+            },
+          },
+        },
+      },
+    } as unknown as CoreConfig;
+
+    const resolved = resolveMatrixConfigForAccount(cfg, "ops", {} as NodeJS.ProcessEnv);
+    expect(resolved.initialSyncLimit).toBeUndefined();
+  });
+
   it("resolves accessToken SecretRef against the provided env", () => {
     const cfg = {
       channels: {
diff --git a/extensions/matrix/src/matrix/client/config.ts b/extensions/matrix/src/matrix/client/config.ts
index 9f6b1245868..22da548d8b4 100644
--- a/extensions/matrix/src/matrix/client/config.ts
+++ b/extensions/matrix/src/matrix/client/config.ts
@@ -1,4 +1,5 @@
 import { formatErrorMessage } from "openclaw/plugin-sdk/error-runtime";
+import { resolveOptionalIntegerOption } from "openclaw/plugin-sdk/number-runtime";
 import { requireRuntimeConfig } from "openclaw/plugin-sdk/plugin-config-runtime";
 import { retryAsync } from "openclaw/plugin-sdk/retry-runtime";
 import {
@@ -412,7 +413,7 @@ function readMatrixAccountConfigField(
 }
 
 function clampMatrixInitialSyncLimit(value: unknown): number | undefined {
-  return typeof value === "number" ? Math.max(0, Math.floor(value)) : undefined;
+  return resolveOptionalIntegerOption(value, { min: 0 });
 }
 
 function buildMatrixNetworkFields(params: {
diff --git a/extensions/matrix/src/matrix/config-update.test.ts b/extensions/matrix/src/matrix/config-update.test.ts
index aaa9eeb5ce8..735e552a0c2 100644
--- a/extensions/matrix/src/matrix/config-update.test.ts
+++ b/extensions/matrix/src/matrix/config-update.test.ts
@@ -54,6 +54,27 @@ describe("updateMatrixAccountConfig", () => {
     expect(account?.userId).toBeUndefined();
   });
 
+  it("does not store non-finite initial sync limits", () => {
+    const cfg = {
+      channels: {
+        matrix: {
+          accounts: {
+            default: {
+              initialSyncLimit: 20,
+            },
+          },
+        },
+      },
+    } as CoreConfig;
+
+    const updated = updateMatrixAccountConfig(cfg, "default", {
+      initialSyncLimit: Number.NaN,
+    });
+
+    expect(updated.channels?.matrix?.initialSyncLimit).toBeUndefined();
+    expect(updated.channels?.matrix?.accounts?.default?.initialSyncLimit).toBeUndefined();
+  });
+
   it("preserves SecretRef auth inputs when updating config", () => {
     const updated = updateMatrixAccountConfig({} as CoreConfig, "default", {
       accessToken: { source: "env", provider: "default", id: "MATRIX_ACCESS_TOKEN" },
diff --git a/extensions/matrix/src/matrix/config-update.ts b/extensions/matrix/src/matrix/config-update.ts
index 69eed293c04..f5b92af1652 100644
--- a/extensions/matrix/src/matrix/config-update.ts
+++ b/extensions/matrix/src/matrix/config-update.ts
@@ -1,4 +1,5 @@
 import { DEFAULT_ACCOUNT_ID, normalizeAccountId } from "openclaw/plugin-sdk/account-id";
+import { resolveOptionalIntegerOption } from "openclaw/plugin-sdk/number-runtime";
 import { coerceSecretRef } from "openclaw/plugin-sdk/secret-ref-runtime";
 import { normalizeSecretInputString } from "openclaw/plugin-sdk/setup";
 import type { CoreConfig, MatrixConfig } from "../types.js";
@@ -188,7 +189,12 @@ export function updateMatrixAccountConfig(
     if (patch.initialSyncLimit === null) {
       delete nextAccount.initialSyncLimit;
     } else {
-      nextAccount.initialSyncLimit = Math.max(0, Math.floor(patch.initialSyncLimit));
+      const initialSyncLimit = resolveOptionalIntegerOption(patch.initialSyncLimit, { min: 0 });
+      if (initialSyncLimit === undefined) {
+        delete nextAccount.initialSyncLimit;
+      } else {
+        nextAccount.initialSyncLimit = initialSyncLimit;
+      }
     }
   }
 
diff --git a/extensions/matrix/src/matrix/monitor/index.ts b/extensions/matrix/src/matrix/monitor/index.ts
index 7411319fffc..25a66ea8c3c 100644
--- a/extensions/matrix/src/matrix/monitor/index.ts
+++ b/extensions/matrix/src/matrix/monitor/index.ts
@@ -3,6 +3,7 @@ import { CHANNEL_APPROVAL_NATIVE_RUNTIME_CONTEXT_CAPABILITY } from "openclaw/plu
 import type { ChannelRuntimeSurface } from "openclaw/plugin-sdk/channel-contract";
 import { waitUntilAbort } from "openclaw/plugin-sdk/channel-outbound";
 import { registerChannelRuntimeContext } from "openclaw/plugin-sdk/channel-runtime-context";
+import { resolveOptionalIntegerOption } from "openclaw/plugin-sdk/number-runtime";
 import {
   GROUP_POLICY_BLOCKED_LABEL,
   resolveThreadBindingIdleTimeoutMsForChannel,
@@ -214,9 +215,7 @@ export async function monitorMatrixProvider(opts: MonitorMatrixOpts = {}): Promi
 
   const auth = await resolveMatrixAuth({ cfg, accountId: effectiveAccountId });
   const resolvedInitialSyncLimit =
-    typeof opts.initialSyncLimit === "number"
-      ? Math.max(0, Math.floor(opts.initialSyncLimit))
-      : auth.initialSyncLimit;
+    resolveOptionalIntegerOption(opts.initialSyncLimit, { min: 0 }) ?? auth.initialSyncLimit;
   const authWithLimit =
     resolvedInitialSyncLimit === auth.initialSyncLimit
       ? auth
diff --git a/src/plugin-sdk/number-runtime.ts b/src/plugin-sdk/number-runtime.ts
index 3fcf4a44e4c..bd5e5921f6c 100644
--- a/src/plugin-sdk/number-runtime.ts
+++ b/src/plugin-sdk/number-runtime.ts
@@ -4,6 +4,7 @@ export {
   parseFiniteNumber,
   resolveIntegerOption,
   resolveNonNegativeIntegerOption,
+  resolveOptionalIntegerOption,
   parseStrictInteger,
   parseStrictFiniteNumber,
   parseStrictNonNegativeInteger,
diff --git a/src/shared/number-coercion.test.ts b/src/shared/number-coercion.test.ts
index 26188c8929a..b72c81551ff 100644
--- a/src/shared/number-coercion.test.ts
+++ b/src/shared/number-coercion.test.ts
@@ -6,6 +6,7 @@ import {
   parseFiniteNumber,
   resolveIntegerOption,
   resolveNonNegativeIntegerOption,
+  resolveOptionalIntegerOption,
   parseStrictFiniteNumber,
   parseStrictInteger,
   parseStrictNonNegativeInteger,
@@ -76,4 +77,12 @@ describe("number-coercion", () => {
     expect(resolveIntegerOption(40, 1, { max: 10 })).toBe(10);
     expect(resolveNonNegativeIntegerOption(Number.NaN, 3.9)).toBe(3);
   });
+
+  test("optional integer option helper rejects non-finite values", () => {
+    expect(resolveOptionalIntegerOption(7.9, { min: 1, max: 10 })).toBe(7);
+    expect(resolveOptionalIntegerOption(Number.NaN, { min: 1 })).toBeUndefined();
+    expect(resolveOptionalIntegerOption(Number.POSITIVE_INFINITY, { min: 1 })).toBeUndefined();
+    expect(resolveOptionalIntegerOption(-4, { min: 0 })).toBe(0);
+    expect(resolveOptionalIntegerOption(40, { max: 10 })).toBe(10);
+  });
 });
diff --git a/src/shared/number-coercion.ts b/src/shared/number-coercion.ts
index 0b77955b124..1840c6f0389 100644
--- a/src/shared/number-coercion.ts
+++ b/src/shared/number-coercion.ts
@@ -107,6 +107,19 @@ export function resolveIntegerOption(
   return range.max === undefined ? minBounded : Math.min(range.max, minBounded);
 }
 
+export function resolveOptionalIntegerOption(
+  value: unknown,
+  range: {
+    min?: number;
+    max?: number;
+  } = {},
+): number | undefined {
+  if (typeof value !== "number" || !Number.isFinite(value)) {
+    return undefined;
+  }
+  return resolveIntegerOption(value, value, range);
+}
+
 export function resolveNonNegativeIntegerOption(value: unknown, fallback: number): number {
   return resolveIntegerOption(value, fallback, { min: 0 });
 }