diff --git a/server/package.json b/server/package.json
index 62336f37..a702f5ad 100644
--- a/server/package.json
+++ b/server/package.json
@@ -32,6 +32,7 @@
         "export-frontend-graphics": "tsx src/scripts/exportFrontendOptimizedGraphics.ts",
         "export-frontend-maps": "tsx src/scripts/exportFrontendOptimizedMaps.ts",
         "export-client-objs": "tsx src/scripts/exportClientObjs.ts",
+        "test:client-activity": "tsx src/scripts/testClientActivityPolicy.ts",
         "start": "node dist/server.js",
         "lint": "eslint './src/**/*.ts'",
         "world-map": "node scripts/build-world-map.cjs",
diff --git a/server/src/scripts/testClientActivityPolicy.ts b/server/src/scripts/testClientActivityPolicy.ts
new file mode 100644
index 00000000..a8c65b10
--- /dev/null
+++ b/server/src/scripts/testClientActivityPolicy.ts
@@ -0,0 +1,51 @@
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import { resolve } from "node:path";
+
+const source = readFileSync(resolve(process.cwd(), "src/server.ts"), "utf8");
+const start = source.indexOf("function trackClientActivity");
+const end = source.indexOf("\n}\n\n(async () => {", start);
+
+assert.ok(start >= 0 && end > start, "trackClientActivity must remain present");
+
+const fn = source.slice(start, end + 2);
+const pingMatch = fn.match(/if \(isPingPacket\) \{([\s\S]*?)\n    \}/);
+assert.ok(pingMatch, "ping branch must remain explicit");
+
+const pingBranch = pingMatch[1];
+assert.match(fn, /ws\.packetCount = Number\(ws\.packetCount \?\? 0\) \+ 1;/, "all packets increment packetCount");
+assert.match(pingBranch, /ws\.lastPingAt = now;/, "ping must refresh transport liveness");
+assert.ok(!pingBranch.includes("lastActivityAt"), "ping must not reset real player activity");
+assert.match(pingBranch, /return;/, "ping must return before non-ping accounting");
+
+for (const forbidden of [
+    "lastPacketAt",
+    "packetCountNonPing",
+    "recentPacketTimestamps",
+    "recentPacketIntervalsMs",
+    "packetTypeCounts",
+]) {
+    assert.ok(!pingBranch.includes(forbidden), `ping must not mutate non-ping metric: ${forbidden}`);
+}
+
+const pingBlockEnd = fn.indexOf("}", fn.indexOf("if (isPingPacket)"));
+const nonPingTail = fn.slice(pingBlockEnd + 1);
+assert.match(nonPingTail, /ws\.lastPacketAt = now;/, "non-ping packets still refresh lastPacketAt");
+assert.match(nonPingTail, /ws\.lastActivityAt = now;/, "non-ping packets still refresh real activity");
+
+const helperStart = source.indexOf("function getClientLivenessReferenceAt");
+const helperEnd = source.indexOf("\n}\n\nfunction getScoutIdleReferenceAt", helperStart);
+assert.ok(helperStart >= 0 && helperEnd > helperStart, "liveness helper must remain present");
+const helperFn = source.slice(helperStart, helperEnd + 2);
+assert.match(helperFn, /client\.lastActivityAt/, "real activity contributes to liveness");
+assert.match(helperFn, /client\.lastPingAt/, "keepalive ping contributes to liveness");
+assert.match(helperFn, /Math\.max\(lastActivityAt, lastPingAt, connectedAt\)/, "freshest liveness signal wins");
+
+const idleStart = source.indexOf("function processIdleCharactersTick");
+const idleEnd = source.indexOf("\n}\n\nfunction getClientLivenessReferenceAt", idleStart);
+assert.ok(idleStart >= 0 && idleEnd > idleStart, "idle sweep must remain present");
+const idleFn = source.slice(idleStart, idleEnd + 2);
+assert.match(idleFn, /getClientLivenessReferenceAt\(client, now\)/, "normal sessions use transport liveness");
+assert.match(idleFn, /getScoutIdleReferenceAt\(client, user\)/, "duplicate scouts keep real-activity policy");
+
+console.log("client activity policy tests passed");
diff --git a/server/src/server.ts b/server/src/server.ts
index c3800bcb..4bce2386 100644
--- a/server/src/server.ts
+++ b/server/src/server.ts
@@ -430,6 +430,9 @@ function trackClientActivity(ws: RuntimeClient, packageID: number) {
     ws.packetCount = Number(ws.packetCount ?? 0) + 1;
 
     if (isPingPacket) {
+        // Keep transport liveness separate from real player activity so
+        // keepalive traffic cannot contaminate AFK/gameplay metrics.
+        ws.lastPingAt = now;
         return;
     }
 
@@ -785,7 +788,7 @@ function processIdleCharactersTick(now: number) {
             continue;
         }
 
-        if (typeof client.lastActivityAt !== "number") {
+        if (typeof client.lastActivityAt !== "number" && typeof client.lastPingAt !== "number") {
             client.lastActivityAt = now;
             continue;
         }
@@ -794,7 +797,7 @@ function processIdleCharactersTick(now: number) {
         const effectiveIdleTimeoutMs = isDuplicateIpScout ? DUPLICATE_IP_IDLE_TIMEOUT_MS : idleCharacterTimeoutMs;
         const idleReferenceAt = isDuplicateIpScout
             ? getScoutIdleReferenceAt(client, user)
-            : Number(client.lastActivityAt ?? now);
+            : getClientLivenessReferenceAt(client, now);
 
         if (now - idleReferenceAt < effectiveIdleTimeoutMs) {
             continue;
@@ -808,6 +811,14 @@ function processIdleCharactersTick(now: number) {
     }
 }
 
+function getClientLivenessReferenceAt(client: RuntimeClient, now: number): number {
+    const lastActivityAt = Number(client.lastActivityAt ?? 0);
+    const lastPingAt = Number(client.lastPingAt ?? 0);
+    const connectedAt = Number(client.connectedAt ?? now);
+
+    return Math.max(lastActivityAt, lastPingAt, connectedAt);
+}
+
 function getScoutIdleReferenceAt(client: RuntimeClient, user: ServerCharacter): number {
     const lastMovedAt = Number(user.lastMovementActivityAt ?? 0);
     const lastCombatActivityAt = Number(user.lastCombatActivityAt ?? 0);
diff --git a/server/src/types/runtime.ts b/server/src/types/runtime.ts
index caef0124..0c2ee0b5 100644
--- a/server/src/types/runtime.ts
+++ b/server/src/types/runtime.ts
@@ -485,6 +485,7 @@ export type RuntimeClient = {
     lastPacketIntervalMs?: number;
     minPacketIntervalMs?: number;
     lastActivityAt?: number;
+    lastPingAt?: number;
     packetTypeCounts?: Record<string, number>;
     nextMapClickAt?: number;
     nextDoorToggleAt?: number;