feat(clients): reachability-probed presence + shareable Decky host management

Add a bounded, trust-agnostic, mDNS-INDEPENDENT QUIC reachability probe and
surface it everywhere saved-host presence is shown, so a host reached over a
routed network (Tailscale/VPN/multicast-filtering LAN) no longer reads Offline
just because it isn't advertising — the display-side companion to the 0.8.4
dial-first connect fix.

Core:
- punktfunk-core: NativeClient::probe (bounded handshake; a real host answers even
  on trust mismatch, a wrong/closed/TCP-only port fails) + punktfunk_probe C ABI
  (ABI_VERSION 3->4, header regenerated).
- pf-client-core: trust::probe_reachable_many (parallel per-host sweep).

Presence pips now read `advertising OR probed-reachable`, refreshed by a ~10-12s
background sweep off the UI thread:
- Linux (relm4): ui_hosts probed map + HostsMsg::Probed sweep.
- Windows (windows-reactor): pf-probe worker -> HostsProps.probed.
- Apple (SwiftUI): HostStore.refreshReachability, driven by HomeView + GamepadHomeView .task.
- Android (Compose): nativeProbe JNI seam + periodic LaunchedEffect (LNP-gated),
  online dot added to the touch HostCard.
- Decky already probes via --list-hosts --probe.

Decky client: make the flatpak client's known-hosts store the single source of
truth via new headless CLI modes (--list-hosts / --add-host / --set-host /
--forget-host / --reset / --reachable). The plugin can now add a host by address,
edit/forget hosts, reset all state (keeping the client identity), and shows
probe-backed online pips — state is shared with the desktop client, not duplicated.

Also lands in-progress Android 17 LNP groundwork (targetSdk 37 +
ACCESS_LOCAL_NETWORK runtime flow, permission dialogs) that was already present in
the working tree.

Verified: cargo check + clippy clean (punktfunk-core, pf-client-core, linux,
android native); android assembleDebug BUILD SUCCESSFUL; decky typecheck + rollup
build clean; probe true/false-positive behaviour exercised against a live host.
Windows and Apple were not compiled locally (no MSVC/Xcode on this Linux box).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/android/app/build.gradle.kts

@@ -11,7 +11,7 @@ plugins {
 
 android {
     namespace = "io.unom.punktfunk"
-    compileSdk = 37 // Android 17 — required by androidx.core 1.19.0; targetSdk stays 36 for now.
+    compileSdk = 37 // Android 17 — required by androidx.core 1.19.0.
 
     defaultConfig {
         // Load from .env if it exists (local dev), otherwise from System.getenv (CI)
@@ -26,7 +26,11 @@ android {
         // the handful of API 31+ APIs we use are runtime-gated (Material You → brand palette, rumble
         // → legacy Vibrator, NEARBY_WIFI/lights/ADPF already gated), so nothing is lost above 28.
         minSdk = 28
-        targetSdk = 36
+        // Android 17: targeting 37 makes Local Network Protection MANDATORY — all LAN traffic (the
+        // QUIC dial, mDNS, WoL, the library fetch) is blocked until the user grants the
+        // ACCESS_LOCAL_NETWORK runtime permission. ConnectScreen owns that request/rationale flow;
+        // don't bump past 37 without re-checking the next release's behavior changes.
+        targetSdk = 37
         val vCode = (props.getProperty("VERSION_CODE") ?: System.getenv("VERSION_CODE"))
         versionCode = vCode?.toInt() ?: 1
         // versionName is the single project version, threaded from CI (a vX.Y.Z release or a

clients/android/app/src/main/AndroidManifest.xml

@@ -19,8 +19,9 @@
          Its absence went unnoticed for weeks because the acquire was wrapped in a silent
          runCatching (now logged). -->
     <uses-permission android:name="android.permission.WAKE_LOCK" />
-    <!-- Enforced from Android 17 (SDK 37) for ALL local-network traffic incl. the QUIC socket.
-         Harmless to declare on earlier releases. -->
+    <!-- Enforced from Android 17 (SDK 37, our targetSdk) for ALL local-network traffic incl. the
+         QUIC socket — a RUNTIME permission (NEARBY_DEVICES group): ConnectScreen requests it on
+         entry and gates every dial/wake on the grant. Harmless to declare on earlier releases. -->
     <uses-permission android:name="android.permission.ACCESS_LOCAL_NETWORK" />
     <!-- Mic uplink to the host's virtual microphone (requested at runtime). -->
     <uses-permission android:name="android.permission.RECORD_AUDIO" />

clients/android/app/src/main/kotlin/io/unom/punktfunk/ConnectDialogs.kt

@@ -155,6 +155,35 @@ internal fun TrustNewHostDialog(
     )
 }
 
+/**
+ * Android 17+ Local Network Protection rationale: ACCESS_LOCAL_NETWORK was denied, so discovery and
+ * every connect are dead — offer the system prompt again and a settings deep link (a permanently-
+ * denied request returns instantly without ever showing the prompt, so "Allow" alone isn't enough).
+ */
+@Composable
+internal fun LocalNetworkDialog(onAllow: () -> Unit, onSettings: () -> Unit, onDismiss: () -> Unit) {
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("Allow local network access") },
+        text = {
+            Text(
+                "Android blocks punktfunk from talking to devices on your network, so it can't " +
+                    "find or reach any host until you allow it. If no prompt appears when you tap " +
+                    "Allow, enable “Nearby devices” for punktfunk in system settings.",
+            )
+        },
+        confirmButton = {
+            TextButton(onClick = onAllow) { Text("Allow") }
+        },
+        dismissButton = {
+            Row {
+                TextButton(onClick = onSettings) { Text("Open settings") }
+                TextButton(onClick = onDismiss) { Text("Not now") }
+            }
+        },
+    )
+}
+
 /** The pinned fingerprint no longer matches — force re-pairing (never a silent re-trust). */
 @Composable
 internal fun FingerprintChangedDialog(

clients/android/app/src/main/kotlin/io/unom/punktfunk/ConnectScreen.kt

@@ -2,7 +2,9 @@ package io.unom.punktfunk
 
 import android.Manifest
 import android.content.Context
+import android.content.Intent
 import android.content.pm.PackageManager
+import android.net.Uri
 import android.os.Build
 import androidx.activity.compose.rememberLauncherForActivityResult
 import androidx.activity.result.contract.ActivityResultContracts
@@ -30,6 +32,7 @@ import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.LaunchedEffect
@@ -37,6 +40,7 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
@@ -44,6 +48,9 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 import androidx.core.content.ContextCompat
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.LifecycleEventObserver
+import androidx.lifecycle.LifecycleOwner
 import io.unom.punktfunk.components.EmptyHostsState
 import io.unom.punktfunk.components.HostCard
 import io.unom.punktfunk.components.SectionLabel
@@ -60,6 +67,7 @@ import io.unom.punktfunk.models.HostStatus
 import io.unom.punktfunk.models.PendingTrust
 import java.util.concurrent.atomic.AtomicBoolean
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 
@@ -111,14 +119,57 @@ fun ConnectScreen(
     // denial used to leave discovery dead forever.
     val discovery = remember { HostDiscovery(context) }
     var discovered by remember { mutableStateOf<List<DiscoveredHost>>(emptyList()) }
+    // Android 17 Local Network Protection: with targetSdk 37, EVERYTHING this screen does — the mDNS
+    // browse, the QUIC dial (UDP 9777), Wake-on-LAN, the library fetch — is blocked until the user
+    // grants ACCESS_LOCAL_NETWORK (a runtime permission in the NEARBY_DEVICES group). Blocked UDP
+    // fails with EPERM, which quinn experiences as a silent handshake timeout — so without this gate
+    // a denial looks exactly like a dead host. Unlike NEARBY_WIFI_DEVICES below, this one is
+    // load-bearing: request it on entry, and surface a denial as an actionable dialog/banner (with a
+    // system-settings deep link) instead of dead-ending on timeouts.
+    var lnpGranted by remember { mutableStateOf(hasLocalNetworkPermission(context)) }
+    var lnpPrompt by remember { mutableStateOf(false) }
+    val localNetLauncher = rememberLauncherForActivityResult(
+        ActivityResultContracts.RequestPermission(),
+    ) { granted ->
+        lnpGranted = granted
+        if (granted) {
+            lnpPrompt = false
+            // The browse started while blocked (its sockets failed or received nothing) — restart it
+            // now that the grant makes them work.
+            discovery.stop()
+            discovery.start()
+        } else {
+            lnpPrompt = true // rationale + "Open settings" (a permanently-denied request returns instantly)
+        }
+    }
     val nearbyLauncher = rememberLauncherForActivityResult(
         ActivityResultContracts.RequestPermission(),
     ) { _ -> /* best-effort hint; discovery runs regardless of the result */ }
     LaunchedEffect(Unit) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU && !hasNearbyPermission(context)) {
+        if (!lnpGranted) {
+            localNetLauncher.launch(Manifest.permission.ACCESS_LOCAL_NETWORK)
+        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU && !hasNearbyPermission(context)) {
+            // The old opportunistic multicast hedge (some OEMs filter multicast without it). On API
+            // 37+ it shares the NEARBY_DEVICES group with ACCESS_LOCAL_NETWORK, so once that is
+            // granted this auto-grants without a second prompt.
             nearbyLauncher.launch(Manifest.permission.NEARBY_WIFI_DEVICES)
         }
     }
+    // Re-check on resume: our dialog deep-links to system settings, and granting there doesn't kill
+    // or otherwise notify the app — this observer is what turns the grant into a live discovery.
+    DisposableEffect(Unit) {
+        val lifecycle = (context as? LifecycleOwner)?.lifecycle
+        val obs = LifecycleEventObserver { _, event ->
+            if (event == Lifecycle.Event.ON_RESUME && !lnpGranted && hasLocalNetworkPermission(context)) {
+                lnpGranted = true
+                lnpPrompt = false
+                discovery.stop()
+                discovery.start()
+            }
+        }
+        lifecycle?.addObserver(obs)
+        onDispose { lifecycle?.removeObserver(obs) }
+    }
     DisposableEffect(Unit) {
         discovery.onChange = { discovered = it }
         discovery.start()
@@ -154,6 +205,29 @@ fun ConnectScreen(
         }
         if (learned) savedHosts = knownHostStore.all()
     }
+    // Saved hosts proven reachable by a QUIC probe this cycle, keyed "address:port" — the
+    // routed-network (Tailscale/VPN) counterpart to mDNS presence, since such hosts never
+    // advertise. OR'd into `isOnline` below so their pips light up. Probe only saved hosts NOT
+    // already seen on mDNS, off the main thread, every ~12 s; gated on LNP (blocked UDP would
+    // just time out). `rememberUpdatedState` keeps the 1 Hz mDNS updates from restarting the loop.
+    var reachable by remember { mutableStateOf<Set<String>>(emptySet()) }
+    val discoveredNow by rememberUpdatedState(discovered)
+    LaunchedEffect(savedHosts, lnpGranted) {
+        if (!lnpGranted) {
+            reachable = emptySet()
+            return@LaunchedEffect
+        }
+        while (true) {
+            val targets = savedHosts.filter { kh -> discoveredNow.none { kh.matches(it) } }
+            reachable = withContext(Dispatchers.IO) {
+                targets
+                    .filter { NativeBridge.nativeProbe(it.address, it.port, 3_000) }
+                    .map { "${it.address}:${it.port}" }
+                    .toSet()
+            }
+            delay(12_000)
+        }
+    }
     // Mint-once on genuine first run; an Unrecoverable store (decrypt failure) surfaces here and
     // refuses to connect — never silently shadow-minting a new identity (which would force re-pair).
     var identity by remember { mutableStateOf<ClientIdentity?>(null) }
@@ -325,6 +399,12 @@ fun ConnectScreen(
         dh: DiscoveredHost? = null,
         manualName: String? = null,
     ) {
+        // Every dial/pair path funnels through here — with local network access denied the connect
+        // can only EPERM its way to a 10 s timeout, so ask instead of pretending to try.
+        if (!lnpGranted) {
+            lnpPrompt = true
+            return
+        }
         val known = knownHostStore.get(targetHost, targetPort)
         val adv = dh?.fingerprint?.lowercase()
         // Label precedence: a saved host keeps its (possibly user-renamed) name; else the discovered
@@ -361,7 +441,7 @@ fun ConnectScreen(
                         title = kh.name,
                         subtitle = "${kh.address}:${kh.port}",
                         filled = true,
-                        online = discovered.any { it.host == kh.address && it.port == kh.port },
+                        online = kh.isOnline(discovered, reachable),
                         paired = kh.paired,
                         knownHost = kh,
                         activate = { connect(kh.address, kh.port) },
@@ -398,7 +478,8 @@ fun ConnectScreen(
             // handle — the touch grid guards the same way with enabled=!connecting), or while the whole
             // console home is cross-fading out.
             navActive = navGate && !connecting && !showManualSheet && pendingTrust == null &&
-                awaiting == null && editTarget == null && optionsTarget == null && waker.waking == null,
+                awaiting == null && editTarget == null && optionsTarget == null &&
+                waker.waking == null && !lnpPrompt,
             onActivate = { it.activate() },
             onOpenLibrary = { it.knownHost?.let(onOpenLibrary) },
             onOpenSettings = onOpenSettings,
@@ -465,6 +546,38 @@ fun ConnectScreen(
                 }
             }
 
+            if (!lnpGranted) {
+                // Local network access denied: discovery can't ever find anything and every connect
+                // would time out — say so at the top, with the fix one tap away, instead of letting
+                // the screen look idle/broken.
+                item(span = { GridItemSpan(maxLineSpan) }) {
+                    Surface(
+                        color = MaterialTheme.colorScheme.errorContainer,
+                        shape = MaterialTheme.shapes.medium,
+                        modifier = Modifier.fillMaxWidth(),
+                    ) {
+                        Column(
+                            Modifier.padding(horizontal = 16.dp, vertical = 12.dp),
+                            horizontalAlignment = Alignment.CenterHorizontally,
+                        ) {
+                            Text(
+                                "Local network access is off",
+                                style = MaterialTheme.typography.titleSmall,
+                                color = MaterialTheme.colorScheme.onErrorContainer,
+                            )
+                            Text(
+                                "Android blocks punktfunk from finding or reaching hosts until you allow it.",
+                                style = MaterialTheme.typography.bodyMedium,
+                                color = MaterialTheme.colorScheme.onErrorContainer,
+                                textAlign = TextAlign.Center,
+                            )
+                            TextButton(onClick = { lnpPrompt = true }) { Text("Allow…") }
+                        }
+                    }
+                    Spacer(Modifier.height(12.dp))
+                }
+            }
+
             if (savedHosts.isEmpty() && discoveredUnsaved.isEmpty()) {
                 item(span = { GridItemSpan(maxLineSpan) }) {
                     EmptyHostsState()
@@ -480,6 +593,7 @@ fun ConnectScreen(
                         name = kh.name,
                         address = "${kh.address}:${kh.port}",
                         status = if (kh.paired) HostStatus.PAIRED else HostStatus.TOFU,
+                        online = kh.isOnline(discovered, reachable),
                         enabled = !connecting,
                         onConnect = { connect(kh.address, kh.port) },
                         onForget = {
@@ -491,8 +605,12 @@ fun ConnectScreen(
                         // through the WakeController so it shows the "Waking…" overlay and waits for
                         // the host to come online (matched by fingerprint, so a new DHCP address on a
                         // cold boot still counts as "up") rather than firing a single silent packet.
-                        onWake = if (kh.mac.isNotEmpty() && discovered.none { kh.matches(it) }) {
+                        onWake = if (kh.mac.isNotEmpty() && !kh.isOnline(discovered, reachable)) {
                             {
+                                // The magic packet is UDP broadcast — LNP-blocked like everything else.
+                                if (!lnpGranted) {
+                                    lnpPrompt = true
+                                } else {
                                     waker.start(
                                         hostName = kh.name,
                                         connectsAfter = false,
@@ -502,6 +620,7 @@ fun ConnectScreen(
                                         onOnline = {},
                                     )
                                 }
+                            }
                         } else {
                             null
                         },
@@ -519,6 +638,7 @@ fun ConnectScreen(
                         name = dh.name,
                         address = "${dh.host}:${dh.port}",
                         status = if (dh.pairingRequired) HostStatus.PAIRING else HostStatus.TOFU,
+                        online = true, // in the discovered list ⇒ live on mDNS right now
                         enabled = !connecting,
                         onConnect = { connect(dh.host, dh.port, dh) },
                         onForget = null,
@@ -528,8 +648,10 @@ fun ConnectScreen(
 
             // Active-discovery hint: discovery runs whenever this screen is up, so while it's
             // scanning but nothing's turned up yet (and we're not mid-connect), show it's working
-            // rather than looking idle/empty.
-            if (!connecting && discovered.isEmpty()) {
+            // rather than looking idle/empty. Suppressed while local network access is denied —
+            // a spinner would be a lie there (the browse can't receive anything); the banner above
+            // owns that state.
+            if (lnpGranted && !connecting && discovered.isEmpty()) {
                 item(span = { GridItemSpan(maxLineSpan) }) {
                     Row(
                         modifier = Modifier.fillMaxWidth().padding(vertical = 12.dp),
@@ -629,17 +751,22 @@ fun ConnectScreen(
 
     // Console host options (Up on a saved carousel tile): Wake / Edit / Forget.
     optionsTarget?.let { kh ->
-        val offline = discovered.none { kh.matches(it) }
+        val offline = !kh.isOnline(discovered, reachable)
         GamepadHostOptionsDialog(
             hostName = kh.name,
             canWake = kh.mac.isNotEmpty() && offline,
             onWake = {
                 optionsTarget = null
+                // The magic packet is UDP broadcast — LNP-blocked like everything else.
+                if (!lnpGranted) {
+                    lnpPrompt = true
+                } else {
                     waker.start(
                         hostName = kh.name, connectsAfter = false, macs = kh.mac, lastIp = kh.address,
                         isOnline = { discovered.any { kh.matches(it) } },
                         onOnline = {},
                     )
+                }
             },
             // A saved host always has a library (it's a knownHost) → offer it when the setting's on,
             // so a TV remote reaches the library here instead of via the Y face button.
@@ -687,6 +814,29 @@ fun ConnectScreen(
         }
     }
 
+    if (lnpPrompt) {
+        // Android 17+ local-network-permission rationale: re-request (a permanently-denied request
+        // returns instantly without a system prompt — hence the settings deep link alongside).
+        val onAllow = {
+            lnpPrompt = false
+            localNetLauncher.launch(Manifest.permission.ACCESS_LOCAL_NETWORK)
+        }
+        val onSettings = {
+            lnpPrompt = false
+            context.startActivity(
+                Intent(
+                    android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS,
+                    Uri.fromParts("package", context.packageName, null),
+                ),
+            )
+        }
+        if (gamepadUi) {
+            GamepadLocalNetworkDialog(onAllow = onAllow, onSettings = onSettings, onDismiss = { lnpPrompt = false })
+        } else {
+            LocalNetworkDialog(onAllow = onAllow, onSettings = onSettings, onDismiss = { lnpPrompt = false })
+        }
+    }
+
     // Topmost: the "Waking…" overlay rides over both the touch grid and the console home.
     WakeOverlay(waker, gamepadUi)
 }
@@ -701,6 +851,18 @@ fun hasNearbyPermission(context: Context): Boolean =
         ContextCompat.checkSelfPermission(context, Manifest.permission.NEARBY_WIFI_DEVICES) ==
         PackageManager.PERMISSION_GRANTED
 
+/**
+ * Whether ACCESS_LOCAL_NETWORK is held (API 37+; below, the permission doesn't exist and local
+ * network access is implicit). Android 17's Local Network Protection blocks ALL local-network
+ * traffic for apps targeting SDK 37 without this runtime grant: UDP sends fail with EPERM, so the
+ * QUIC dial surfaces as a silent handshake timeout and the mDNS browse receives nothing. Unlike
+ * [hasNearbyPermission] this is load-bearing — nothing on the connect screen works without it.
+ */
+fun hasLocalNetworkPermission(context: Context): Boolean =
+    Build.VERSION.SDK_INT < Build.VERSION_CODES.CINNAMON_BUN ||
+        ContextCompat.checkSelfPermission(context, Manifest.permission.ACCESS_LOCAL_NETWORK) ==
+        PackageManager.PERMISSION_GRANTED
+
 /**
  * True when a saved host and a discovered advert are the same machine — matched by certificate
  * fingerprint when both carry it (so it survives a DHCP address change), else by address:port.
@@ -711,3 +873,11 @@ private fun KnownHost.matches(dh: DiscoveredHost): Boolean {
     if (!advFp.isNullOrEmpty() && fpHex.isNotEmpty() && fpHex.lowercase() == advFp) return true
     return address == dh.host && port == dh.port
 }
+
+/**
+ * True when a saved host is reachable RIGHT NOW: advertising on mDNS OR answering the QUIC probe
+ * (a host reached over a routed network — Tailscale/VPN — never advertises but is reachable). The
+ * display-side companion to dial-first: presence no longer means "on this LAN".
+ */
+private fun KnownHost.isOnline(discovered: List<DiscoveredHost>, reachable: Set<String>): Boolean =
+    discovered.any { matches(it) } || reachable.contains("$address:$port")

clients/android/app/src/main/kotlin/io/unom/punktfunk/GamepadDialogs.kt

@@ -229,6 +229,29 @@ fun GamepadHostOptionsDialog(
     }
 }
 
+/** Console counterpart of [LocalNetworkDialog] — the Android 17+ ACCESS_LOCAL_NETWORK rationale. */
+@Composable
+fun GamepadLocalNetworkDialog(onAllow: () -> Unit, onSettings: () -> Unit, onDismiss: () -> Unit) {
+    GamepadDialog(
+        title = "Allow local network access",
+        onDismiss = onDismiss,
+        actions = listOf(
+            DialogAction("Allow", primary = true, onClick = onAllow),
+            DialogAction("Open settings", onClick = onSettings),
+            DialogAction("Not now", onClick = onDismiss),
+        ),
+    ) {
+        DialogText(
+            "Android blocks punktfunk from talking to devices on your network, so it can't find " +
+                "or reach any host until you allow it.",
+        )
+        DialogText(
+            "If no prompt appears after Allow, enable “Nearby devices” for punktfunk in " +
+                "system settings.",
+        )
+    }
+}
+
 @Composable
 fun GamepadTrustNewDialog(pt: PendingTrust, onTrust: () -> Unit, onPairInstead: () -> Unit, onDismiss: () -> Unit) {
     GamepadDialog(

clients/android/app/src/main/kotlin/io/unom/punktfunk/components/HostComponents.kt

@@ -2,6 +2,7 @@ package io.unom.punktfunk.components
 
 import androidx.compose.foundation.background
 import androidx.compose.foundation.border
+import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
@@ -56,6 +57,7 @@ fun HostCard(
     name: String,
     address: String,
     status: HostStatus,
+    online: Boolean = false,
     enabled: Boolean,
     onConnect: () -> Unit,
     onForget: (() -> Unit)?,
@@ -105,8 +107,14 @@ fun HostCard(
                     textAlign = TextAlign.Center,
                 )
                 Spacer(Modifier.height(12.dp))
+                Row(
+                    verticalAlignment = Alignment.CenterVertically,
+                    horizontalArrangement = Arrangement.spacedBy(12.dp),
+                ) {
+                    PresencePill(online)
                     StatusPill(status)
                 }
+            }
 
             if (onForget != null || onEdit != null || onWake != null) {
                 var menu by remember { mutableStateOf(false) }
@@ -173,6 +181,27 @@ fun HostAvatar(name: String) {
     }
 }
 
+/**
+ * A small dot + label for live presence: green Online when the host advertises on mDNS OR answers
+ * the reachability probe (so a routed/VPN host that never advertises still reads Online), dimmed
+ * Offline otherwise.
+ */
+@Composable
+fun PresencePill(online: Boolean) {
+    val color =
+        if (online) MaterialTheme.colorScheme.primary
+        else MaterialTheme.colorScheme.onSurfaceVariant
+    Row(verticalAlignment = Alignment.CenterVertically) {
+        Box(Modifier.size(8.dp).clip(CircleShape).background(color))
+        Spacer(Modifier.width(6.dp))
+        Text(
+            if (online) "Online" else "Offline",
+            style = MaterialTheme.typography.labelMedium,
+            color = color,
+        )
+    }
+}
+
 /** A small colored dot + label for the host's trust state. */
 @Composable
 fun StatusPill(status: HostStatus) {

clients/android/build.gradle.kts

@@ -3,7 +3,7 @@
 // here (version + apply false) so modules can apply it version-less; its version pins the build's
 // Kotlin (compose-compiler and Kotlin release in lockstep), keeping them matched.
 // Toolchain: AGP 9.2.0 · Gradle 9.4.1 · Kotlin/Compose-compiler 2.3.21 · JDK 21 · Compose BOM
-// 2026.05.01 · compileSdk 37 · targetSdk 36 · minSdk 31.
+// 2026.05.01 · compileSdk 37 · targetSdk 37 · minSdk 28.
 plugins {
     id("com.android.application") version "9.2.1" apply false
     id("com.android.library") version "9.2.1" apply false

clients/android/kit/src/main/kotlin/io/unom/punktfunk/kit/NativeBridge.kt

@@ -126,6 +126,15 @@ object NativeBridge {
      */
     external fun nativeWakeOnLan(macsCsv: String, lastIp: String): Boolean
 
+    /**
+     * Bounded, trust-agnostic QUIC reachability probe to [host]:[port] (mDNS-independent): true if
+     * the host completed the handshake within [timeoutMs]. No pin/identity presented. Lets a saved
+     * host reached over a routed network (Tailscale/VPN/another subnet) — which never advertises on
+     * mDNS — still show as online. Blocking (builds its own runtime) — run on a background
+     * dispatcher, never the main thread.
+     */
+    external fun nativeProbe(host: String, port: Int, timeoutMs: Int): Boolean
+
     /**
      * Apply the user's "Low-latency mode (experimental)" toggle to the process-wide transport
      * defaults — today just DSCP/QoS marking on the media sockets. Must be called BEFORE

clients/android/native/src/lib.rs

@@ -42,6 +42,9 @@ mod stats;
 // Ungated like `discovery`: pure `jni` + `punktfunk_core::wol` (no Android framework), so it links
 // into the host workspace build too. Kotlin only ever calls it on device.
 mod wol;
+// Ungated like `wol`: pure `jni` + `punktfunk_core::client` (the reachability probe). Kotlin calls
+// it off the main thread to light saved-host "online" pips independently of mDNS.
+mod probe;
 
 /// Initialize `android_logger` once when the JVM loads the library. Logs land in logcat under the
 /// `punktfunk` tag. Core `tracing` events (transport warnings: socket-buffer clamp, QoS failures)

clients/android/native/src/probe.rs

@@ -0,0 +1,36 @@
+//! JNI seam for the reachability probe: a bounded, trust-agnostic QUIC handshake to a saved host
+//! (`punktfunk_core::client::NativeClient::probe`). Like [`crate::wol`] it takes no session handle
+//! and links into the host workspace build (pure `jni` + `punktfunk_core`). Kotlin calls it
+//! periodically, on a background dispatcher, to light the "online" pip for saved hosts that never
+//! advertise on mDNS (reached over Tailscale / VPN / another subnet) — the display-side companion
+//! to the dial-first connect fix.
+
+use jni::objects::{JObject, JString};
+use jni::sys::{jboolean, jint};
+use jni::JNIEnv;
+use punktfunk_core::client::NativeClient;
+use std::time::Duration;
+
+/// `NativeBridge.nativeProbe(host, port, timeoutMs): Boolean` — true if `host:port` completed a
+/// QUIC handshake within `timeoutMs`. No pin/identity presented (trust-agnostic), mDNS-independent.
+/// Blocking (builds its own runtime) — Kotlin runs it on `Dispatchers.IO`, never the main thread.
+#[no_mangle]
+pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeProbe<'local>(
+    mut env: JNIEnv<'local>,
+    _this: JObject<'local>,
+    host: JString<'local>,
+    port: jint,
+    timeout_ms: jint,
+) -> jboolean {
+    let host: String = match env.get_string(&host) {
+        Ok(s) => s.into(),
+        Err(_) => return 0,
+    };
+    let port = port.clamp(0, u16::MAX as jint) as u16;
+    let timeout = Duration::from_millis(timeout_ms.max(0) as u64);
+    if NativeClient::probe(&host, port, timeout) {
+        1
+    } else {
+        0
+    }
+}

clients/apple/Sources/PunktfunkClient/Home/GamepadHomeView.swift

@@ -96,6 +96,14 @@ struct GamepadHomeView: View {
         .background { GamepadScreenBackground() }
         .onAppear { discovery.start() }
         .onDisappear { discovery.stop() }
+        // Reachability sweep (mDNS-independent) so routed/VPN hosts that never advertise still show
+        // Online — the console mirror of HomeView's `.task`; cancelled on disappear.
+        .task {
+            while !Task.isCancelled {
+                await store.refreshReachability(discovery: discovery)
+                try? await Task.sleep(for: .seconds(10))
+            }
+        }
         // The settings / add-host screens take over the controller (the carousel's `isActive`
         // gate above). iOS presents them full screen — the immersive console feel; macOS has no
         // fullScreenCover, so they become generously sized sheets over the dimmed launcher.
@@ -218,13 +226,16 @@ struct GamepadHomeView: View {
                 id: .saved(host.id),
                 title: host.displayName,
                 subtitle: "\(host.address):\(String(host.port))",
-                isOnline: discovery.advertises(host),
+                // Online = advertising on mDNS OR proven reachable by the probe (a routed/VPN host
+                // never advertises); the wake item is offered only when neither holds.
+                isOnline: discovery.advertises(host) || store.probedOnline.contains(host.id),
                 isPaired: host.pinnedSHA256 != nil,
                 isConnecting: model.phase == .connecting && model.activeHost?.id == host.id,
                 filled: true,
                 hasLibrary: true,
                 canWake: PunktfunkConnection.wakeOnLANAvailable
-                    && !discovery.advertises(host) && !host.wakeMacs.isEmpty,
+                    && !discovery.advertises(host) && !store.probedOnline.contains(host.id)
+                    && !host.wakeMacs.isEmpty,
                 activate: { connect(host) })
         }
         let discovered = discovery.unsaved(among: store.hosts).map { d in

clients/apple/Sources/PunktfunkClient/Home/HomeView.swift

@@ -76,6 +76,17 @@ struct HomeView: View {
             // session. The home appears/disappears as the stream swaps in and out.
             .onAppear { discovery.start() }
             .onDisappear { discovery.stop() }
+            // Reachability sweep while the grid is up: a saved host reached only over a routed
+            // network (Tailscale/VPN) never advertises on mDNS, so `advertises` can't see it. Probe
+            // every non-advertising saved host ~every 10 s and publish the reachable set for the
+            // pips (`isOnline` above OR's it in). The `.task` is cancelled on disappear, matching
+            // `discovery.stop()`.
+            .task {
+                while !Task.isCancelled {
+                    await store.refreshReachability(discovery: discovery)
+                    try? await Task.sleep(for: .seconds(10))
+                }
+            }
             #if os(tvOS)
             // Pushed routes — the Settings-app navigation feel (push animation, Menu
             // pops) instead of modal overlays.
@@ -157,7 +168,7 @@ struct HomeView: View {
         let onBrowseLibrary: (() -> Void)? = libraryEnabled ? { libraryTarget = host } : nil
         return HostCardView(
             host: host,
-            isOnline: discovery.advertises(host),
+            isOnline: discovery.advertises(host) || store.probedOnline.contains(host.id),
             isConnecting: model.phase == .connecting && model.activeHost?.id == host.id,
             isMostRecent: host.id == mostRecentHostID,
             isBusy: model.isBusy,

clients/apple/Sources/PunktfunkClient/Stores/HostStore.swift

@@ -81,6 +81,11 @@ final class HostStore: ObservableObject {
         didSet { persist() }
     }
 
+    /// Saved hosts proven reachable by the periodic QUIC probe (by id) — the mDNS-independent
+    /// counterpart to discovery presence, OR'd into the "online" pip so a routed/VPN host that
+    /// never advertises still reads Online. Not persisted (it's live reachability, not config).
+    @Published var probedOnline: Set<StoredHost.ID> = []
+
     init() {
         if let data = UserDefaults.standard.data(forKey: Self.key),
            let decoded = try? JSONDecoder().decode([StoredHost].self, from: data) {
@@ -110,6 +115,23 @@ final class HostStore: ObservableObject {
         hosts[i].lastConnected = Date()
     }
 
+    /// One reachability sweep, driving `probedOnline`: probe every saved host NOT currently
+    /// advertising on `discovery` (mDNS already answers for those) off the main actor via a bounded,
+    /// trust-agnostic QUIC handshake, then publish the reachable set. This is the mDNS-independent
+    /// half of presence — a host reached over a routed network (Tailscale/VPN) never advertises but
+    /// answers here. Call in a loop from a home view's `.task` (cancelled on disappear).
+    func refreshReachability(discovery: HostDiscovery) async {
+        let targets = hosts.filter { !discovery.advertises($0) }
+        var online: Set<StoredHost.ID> = []
+        for host in targets {
+            let reachable = await Task.detached(priority: .utility) {
+                PunktfunkConnection.probe(host: host.address, port: host.port)
+            }.value
+            if reachable { online.insert(host.id) }
+        }
+        probedOnline = online
+    }
+
     func pin(_ hostID: UUID, fingerprint: Data) {
         guard let i = hosts.firstIndex(where: { $0.id == hostID }) else { return }
         hosts[i].pinnedSHA256 = fingerprint

clients/apple/Sources/PunktfunkKit/Connection/PunktfunkConnection.swift

@@ -112,6 +112,16 @@ public extension PunktfunkConnection {
         }
         return rc == statusOK
     }
+
+    /// Bounded, trust-agnostic QUIC-handshake reachability probe to `host:port` — mDNS-INDEPENDENT,
+    /// so a host reached over a routed network (Tailscale/VPN/another subnet), which never
+    /// advertises, still reports reachable. No pin/identity presented. The display-side companion
+    /// to the dial-first connect fix: lets saved-host "online" pips reflect real reachability.
+    /// Blocking (builds its own runtime) — call OFF the main thread.
+    static func probe(host: String, port: UInt16, timeoutMs: UInt32 = 1500) -> Bool {
+        let rc: Int32 = host.withCString { punktfunk_probe($0, port, timeoutMs) }
+        return rc == statusOK
+    }
 }
 
 public final class PunktfunkConnection {

clients/decky/main.py

@@ -300,6 +300,98 @@ async def _flatpak_capture(args: list[str], timeout: float = 20.0) -> tuple[int,
         return -1, ""
 
 
+async def _run_client(client_args: list[str], timeout: float = 20.0) -> tuple[int, str, str]:
+    """Run the flatpak CLIENT headlessly (``flatpak run … io.unom.Punktfunk <client_args>``) with
+    the user-session env, returning ``(returncode, stdout, stderr)`` with SEPARATE pipes so a JSON
+    payload on stdout stays clean of the client's log lines on stderr. ``(-1, "", "")`` when
+    flatpak is missing or the call errors/times out. This is the single entry point for the
+    headless host-store modes (``--list-hosts`` / ``--add-host`` / ``--set-host`` /
+    ``--forget-host`` / ``--reset`` / ``--reachable``), which mutate the SAME
+    ``client-known-hosts.json`` the desktop client reads — so state is shared, not duplicated."""
+    flatpak = _flatpak()
+    if not flatpak:
+        return -1, "", ""
+    argv = [flatpak, "run", "--arch=x86_64", APP_ID, *client_args]
+    proc = None
+    try:
+        proc = await asyncio.create_subprocess_exec(
+            *argv,
+            stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.PIPE,
+            env=_flatpak_env(),
+        )
+        out, err = await asyncio.wait_for(proc.communicate(), timeout=timeout)
+        rc = proc.returncode if proc.returncode is not None else -1
+        return (
+            rc,
+            (out or b"").decode("utf-8", "replace"),
+            (err or b"").decode("utf-8", "replace"),
+        )
+    except asyncio.TimeoutError:
+        decky.logger.warning("client %s timed out", " ".join(client_args))
+        if proc:
+            try:
+                proc.kill()
+            except ProcessLookupError:
+                pass
+        return -1, "", ""
+    except Exception:  # noqa: BLE001
+        decky.logger.exception("client %s failed", " ".join(client_args))
+        return -1, "", ""
+
+
+# The QAM panel and the full page each mount their own hosts view, and Gaming Mode remounts the
+# QAM often — every mount calls list_hosts, which spawns a flatpak cold-start plus a reachability
+# probe. Cache the last result briefly so back-to-back opens reuse it instead of re-probing; any
+# mutation (add/edit/forget/reset/pair) invalidates it so a change shows up immediately.
+_HOSTS_TTL_S = 12.0
+_hosts_cache: dict = {"at": 0.0, "probed": None, "data": None}
+
+
+def _invalidate_hosts_cache() -> None:
+    _hosts_cache["data"] = None
+
+
+def _read_known_hosts() -> list[dict]:
+    """The saved-hosts store read straight off disk — the fallback for a client too old to have
+    ``--list-hosts``. Same file the desktop client owns; `online` is left ``None`` (unknown)
+    because a direct read has no reachability signal."""
+    try:
+        data = json.loads((_client_config_dir() / "client-known-hosts.json").read_text())
+    except (OSError, json.JSONDecodeError):
+        return []
+    hosts = data.get("hosts", []) if isinstance(data, dict) else []
+    out: list[dict] = []
+    for h in hosts:
+        if not isinstance(h, dict) or not h.get("addr"):
+            continue
+        out.append({
+            "name": str(h.get("name") or h.get("addr", "")),
+            "addr": str(h.get("addr", "")),
+            "port": int(h.get("port", 9777) or 9777),
+            "fp_hex": str(h.get("fp_hex", "")),
+            "paired": bool(h.get("paired", False)),
+            "mac": h.get("mac") if isinstance(h.get("mac"), list) else [],
+            "last_used": h.get("last_used"),
+            "online": None,
+        })
+    return out
+
+
+def _mutation_result(rc: int, err: str, op: str) -> dict:
+    """Map a headless host-store mutation's exit status to a UI-stable result. ``rc == -1`` means
+    the flatpak call never ran (missing/timed out); a nonzero rc from a client that PREDATES the
+    mode falls through to GTK init and fails headless — classified ``client-outdated`` so the UI
+    can prompt an update instead of showing a cryptic error."""
+    if rc == 0:
+        return {"ok": True}
+    if rc == -1:
+        return {"ok": False, "error": "client-unavailable"}
+    code = _classify_library_error(err)
+    detail = (err.strip().splitlines() or [f"{op} failed"])[-1]
+    decky.logger.warning("%s failed (rc=%s): %s", op, rc, detail)
+    return {"ok": False, "error": code, "detail": detail}
+
+
 def _field_from(text: str, name: str) -> str:
     """Pull ``<name>: value`` out of ``flatpak info`` / ``remote-info`` output (e.g. ``Commit``,
     ``Origin``)."""
@@ -483,6 +575,7 @@ class Plugin:
                 if tok.startswith("fp="):
                     fp = tok[3:]
             decky.logger.info("paired %s:%s", host, port)
+            _invalidate_hosts_cache()  # the store gained a paired entry — reflect it next list
             return {"ok": True, "fp": fp}
         decky.logger.warning("pairing failed (rc=%s): %s", proc.returncode, err.strip() or out.strip())
         # Surface the client's own one-line reason (wrong PIN / not armed) to the UI.
@@ -684,6 +777,125 @@ class Plugin:
             decky.logger.exception("could not write settings")
             return {"ok": False, "error": str(exc)}
 
+    # ---- Shared known-hosts store (the SAME file the desktop client reads/writes) ----
+
+    async def list_hosts(self, probe: bool = True) -> dict:
+        """The saved-hosts store as a list — the SAME ``client-known-hosts.json`` the desktop
+        client owns, so a host added/renamed/paired in either surface shows in both. With
+        ``probe`` each host carries a live ``online`` bool from a mDNS-INDEPENDENT reachability
+        probe (a Tailscale/VPN host is no longer shown offline just because it doesn't advertise);
+        ``online`` is ``None`` when reachability is unknown. Prefers the client's ``--list-hosts``
+        mode; falls back to reading the JSON directly when the installed client predates it."""
+        now = time.monotonic()
+        cache = _hosts_cache
+        if (
+            cache["data"] is not None
+            and cache["probed"] == bool(probe)
+            and (now - cache["at"]) < _HOSTS_TTL_S
+        ):
+            return cache["data"]
+
+        args = ["--list-hosts"] + (["--probe"] if probe else [])
+        rc, out, err = await _run_client(args, timeout=30.0)
+        result: dict | None = None
+        if rc == 0:
+            try:
+                data = json.loads(out)
+                hosts = data.get("hosts", []) if isinstance(data, dict) else []
+                result = {"ok": True, "hosts": hosts, "probed": bool(probe)}
+            except json.JSONDecodeError:
+                decky.logger.warning("list-hosts: unparseable output: %s", out[:200])
+        elif rc != -1:
+            decky.logger.info(
+                "list-hosts unavailable (%s); reading store directly",
+                _classify_library_error(err),
+            )
+        if result is None:
+            # Fallback: read the store off disk (old client / no --list-hosts) — no reachability.
+            result = {"ok": True, "hosts": _read_known_hosts(), "probed": False, "fallback": True}
+        cache.update(at=now, probed=bool(probe), data=result)
+        return result
+
+    async def add_host(self, target: str, name: str = "", fp: str = "") -> dict:
+        """Save a host by address so it can be paired/streamed even when mDNS never sees it (a
+        Tailscale/VPN box). Without ``fp`` it's an unpaired placeholder the user pairs next; a
+        later pair replaces it with the fingerprinted entry. Returns ``{ok, error?, detail?}``."""
+        args = ["--add-host", target.strip()]
+        if name.strip():
+            args += ["--host-label", name.strip()]
+        if fp.strip():
+            args += ["--fp", fp.strip()]
+        rc, _out, err = await _run_client(args, timeout=20.0)
+        _invalidate_hosts_cache()
+        return _mutation_result(rc, err, "add-host")
+
+    async def edit_host(
+        self, selector: str, name: str = "", addr: str = "", port: int = 0
+    ) -> dict:
+        """Edit a saved host — rename and/or re-point its address. ``selector`` is the host's
+        cert fingerprint (survives IP changes) or its current ``addr[:port]``. Empty fields are
+        left untouched. Returns ``{ok, error?, detail?}``."""
+        args = ["--set-host", selector]
+        if name.strip():
+            args += ["--host-label", name.strip()]
+        if addr.strip():
+            args += ["--addr", addr.strip()]
+        if port:
+            args += ["--port", str(int(port))]
+        rc, _out, err = await _run_client(args, timeout=20.0)
+        _invalidate_hosts_cache()
+        return _mutation_result(rc, err, "set-host")
+
+    async def forget_host(self, selector: str) -> dict:
+        """Remove a saved host (by fingerprint or ``addr[:port]``) — drops the pinned
+        fingerprint, so a later connect must re-pair/trust. Idempotent."""
+        rc, _out, err = await _run_client(["--forget-host", selector], timeout=20.0)
+        _invalidate_hosts_cache()
+        return _mutation_result(rc, err, "forget-host")
+
+    async def reset_config(self) -> dict:
+        """Reset this device's Punktfunk state: saved hosts, stream settings, and the plugin's
+        pinned games. The client's persistent IDENTITY (client-cert/key.pem) is KEPT so the box
+        isn't seen as brand-new everywhere (re-pairing re-adds hosts). Prefers the client's
+        ``--reset``; if that's unavailable (old client / no flatpak) it clears the shared JSON
+        stores directly. The plugin-owned pins file is always cleared here (``--reset`` never
+        touches it)."""
+        rc, _out, _err = await _run_client(["--reset"], timeout=20.0)
+        _invalidate_hosts_cache()
+        errors: list[str] = []
+        if rc != 0:
+            decky.logger.info("reset: --reset unavailable (rc=%s); clearing stores directly", rc)
+            for name in ("client-known-hosts.json", "client-gtk-settings.json"):
+                try:
+                    (_client_config_dir() / name).unlink()
+                except FileNotFoundError:
+                    pass
+                except OSError as exc:
+                    errors.append(f"{name}: {exc}")
+        try:
+            _pins_path().unlink()  # plugin-owned; the client's --reset leaves it alone
+        except FileNotFoundError:
+            pass
+        except OSError as exc:
+            errors.append(f"pins: {exc}")
+        if errors:
+            return {"ok": False, "error": "; ".join(errors)}
+        return {"ok": True}
+
+    async def probe_host(self, target: str) -> dict:
+        """Reachability of one ``host[:port]`` via the client's mDNS-independent QUIC probe —
+        for a "test this address" check. ``{ok: True, online: bool}`` when determined, else
+        ``{ok: False, error}`` (flatpak missing / client too old)."""
+        rc, _out, err = await _run_client(["--reachable", target.strip()], timeout=8.0)
+        if rc == 0:
+            return {"ok": True, "online": True}
+        if rc == 1:
+            return {"ok": True, "online": False}
+        return {
+            "ok": False,
+            "error": _classify_library_error(err) if err.strip() else "client-unavailable",
+        }
+
     async def kill_stream(self) -> dict:
         """Force-stop a wedged stream client (``flatpak kill``)."""
         flatpak = _flatpak()

clients/decky/src/backend.ts

@@ -54,6 +54,38 @@ export interface PairResult {
   error?: string;
 }
 
+// A host in the SHARED saved-hosts store (client-known-hosts.json) — the same file the desktop
+// client reads/writes, so add/rename/pair in either surface shows up in both. `online` comes
+// from a mDNS-INDEPENDENT reachability probe (a Tailscale/VPN host isn't shown offline just
+// because it doesn't advertise); `null` means reachability is unknown (probe skipped or a client
+// too old for `--list-hosts`, which then also can't probe).
+export interface SavedHost {
+  name: string;
+  addr: string;
+  port: number;
+  fp_hex: string; // host cert fingerprint (lowercase hex); "" for a not-yet-paired manual entry
+  paired: boolean;
+  mac: string[];
+  last_used: number | null;
+  online: boolean | null;
+}
+
+export interface HostsResult {
+  ok: boolean;
+  hosts: SavedHost[];
+  probed: boolean;
+  fallback?: boolean; // true when read straight off disk (client too old for --list-hosts)
+}
+
+// The result of a host-store mutation (add/edit/forget). `error` is a stable code:
+// "client-unavailable" (flatpak missing) | "client-outdated" (client predates the mode) |
+// "unreachable"/"http"/… (from the client) | "client-error" (generic; see `detail`).
+export interface MutationResult {
+  ok: boolean;
+  error?: string;
+  detail?: string;
+}
+
 export interface RunnerInfo {
   runner: string; // absolute path to bin/punktfunkrun.sh
   app_id: string; // flatpak app id
@@ -129,6 +161,32 @@ export const killStream = callable<[], { ok: boolean }>("kill_stream");
 export const wake = callable<[host: string, port: number], { ok: boolean; error?: string }>(
   "wake",
 );
+// ---- Shared saved-hosts store (the SAME client-known-hosts.json the desktop client owns) ----
+// The saved hosts, each annotated with a live (mDNS-independent) `online` probe when `probe` is
+// true. Falls back to a direct JSON read (no reachability) on a client too old for --list-hosts.
+export const listHosts = callable<[probe: boolean], HostsResult>("list_hosts");
+// Save a host by address (survives mDNS-blind networks). `fp` empty = unpaired placeholder to
+// pair next; a later pair replaces it with the fingerprinted entry.
+export const addHost = callable<[target: string, name: string, fp: string], MutationResult>(
+  "add_host",
+);
+// Rename and/or re-point a saved host. `selector` = its fingerprint (survives IP change) or
+// current addr[:port]; empty fields are left untouched.
+export const editHost = callable<
+  [selector: string, name: string, addr: string, port: number],
+  MutationResult
+>("edit_host");
+// Remove a saved host by fingerprint or addr[:port] (idempotent).
+export const forgetHost = callable<[selector: string], MutationResult>("forget_host");
+// Reset this device's Punktfunk state (saved hosts + stream settings + pins); KEEPS the client
+// identity so the box isn't seen as new everywhere (re-pairing re-adds hosts).
+export const resetConfig = callable<[], { ok: boolean; error?: string }>("reset_config");
+// Reachability of one host[:port] via the client's mDNS-independent QUIC probe (a "test address"
+// check). `{ ok: true, online }` when determined, else `{ ok: false, error }`.
+export const probeHost = callable<
+  [target: string],
+  { ok: boolean; online?: boolean; error?: string }
+>("probe_host");
 export const checkUpdate = callable<[force: boolean], UpdateInfo>("check_update");
 // Update the flatpak client in the user installation (`flatpak update --user -y io.unom.Punktfunk`).
 export const updateClient = callable<

clients/decky/src/hooks.ts

@@ -8,7 +8,10 @@ import {
   GameEntry,
   getPins,
   Host,
+  listHosts,
   PinnedGame,
+  resetConfig,
+  SavedHost,
   setPins as setPinsBackend,
   updateClient,
   UpdateInfo,
@@ -59,6 +62,152 @@ export function useHosts() {
   return { hosts, scanning, refresh };
 }
 
+// ----------------------------------------------------------------------------------------
+// Saved hosts — the SHARED known-hosts store (client-known-hosts.json), the same file the
+// desktop client reads/writes. Fetched WITH a reachability probe so a host reached over a
+// routed network (Tailscale/VPN) reports online without ever appearing on mDNS.
+// ----------------------------------------------------------------------------------------
+export function useSavedHosts() {
+  const [saved, setSaved] = useState<SavedHost[]>([]);
+  const [loading, setLoading] = useState(false);
+
+  const refresh = useCallback(async () => {
+    setLoading(true);
+    try {
+      const r = await listHosts(true);
+      setSaved(r.hosts ?? []);
+    } catch {
+      /* backend unavailable — keep the current view */
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  useEffect(() => {
+    void refresh();
+  }, [refresh]);
+
+  return { saved, loading, refresh };
+}
+
+/**
+ * One host as the UI shows it — the union of the saved store and the live mDNS scan. A saved
+ * host is ONLINE when it either advertises on mDNS OR answers the reachability probe (so
+ * mDNS-blind-but-reachable hosts stop reading as offline). Discovered hosts not in the store
+ * are appended as unsaved rows.
+ */
+export interface HostView {
+  name: string;
+  addr: string;
+  port: number;
+  fp: string; // "" for a saved-but-unpaired placeholder
+  paired: boolean; // PIN-paired specifically (a TOFU host has fp but paired=false)
+  online: boolean;
+  saved: boolean; // present in the known-hosts store
+  pairPolicy: string; // the advert's policy ("required"|"optional"), "" when not advertising
+  mgmt: number; // advertised mgmt-API port (0 = not advertised → default)
+  id: string; // advertised stable host id ("" when not advertising)
+}
+
+function advertMatchesSaved(a: Host, s: SavedHost): boolean {
+  return (
+    (!!s.fp_hex && !!a.fp && s.fp_hex.toLowerCase() === a.fp.toLowerCase()) ||
+    (s.addr === a.host && s.port === a.port)
+  );
+}
+
+export function mergeHosts(saved: SavedHost[], discovered: Host[]): HostView[] {
+  const views: HostView[] = saved.map((s) => {
+    // Prefer a live advert's address (a host may have moved DHCP leases since it was saved).
+    const advert = discovered.find((a) => advertMatchesSaved(a, s));
+    return {
+      name: s.name || s.addr,
+      addr: advert?.host ?? s.addr,
+      port: advert?.port ?? s.port,
+      fp: s.fp_hex || advert?.fp || "",
+      paired: s.paired,
+      online: !!advert || s.online === true,
+      saved: true,
+      pairPolicy: advert?.pair ?? "",
+      mgmt: advert?.mgmt ?? 0,
+      id: advert?.id ?? "",
+    };
+  });
+  for (const a of discovered) {
+    if (saved.some((s) => advertMatchesSaved(a, s))) {
+      continue; // already rendered as its saved card (with a live pip)
+    }
+    views.push({
+      name: a.name,
+      addr: a.host,
+      port: a.port,
+      fp: a.fp,
+      paired: a.paired,
+      online: true,
+      saved: false,
+      pairPolicy: a.pair,
+      mgmt: a.mgmt,
+      id: a.id,
+    });
+  }
+  return views;
+}
+
+/**
+ * True when this host must be paired before it can stream. A saved host is streamable once it
+ * has a pinned fingerprint (PIN-paired OR TOFU-trusted); a saved placeholder (no fp yet) must be
+ * paired. For an unsaved discovered host we keep the advertised-policy rule the UI always used.
+ */
+export function needsPair(v: HostView): boolean {
+  return v.saved ? v.fp === "" : v.pairPolicy === "required" && !v.paired;
+}
+
+/** Adapt a merged view back into the `Host` shape the pair/library/stream helpers consume. */
+export function toHost(v: HostView): Host {
+  return {
+    name: v.name,
+    host: v.addr,
+    port: v.port,
+    pair: v.pairPolicy || (needsPair(v) ? "required" : "optional"),
+    fp: v.fp,
+    proto: "",
+    paired: v.paired,
+    id: v.id,
+    mgmt: v.mgmt,
+  };
+}
+
+/** Is a pinned game's host currently online, considering BOTH the live scan and saved probe? */
+export function pinIsOnline(pin: PinnedGame, views: HostView[]): boolean {
+  const fp = pin.host_fp.toLowerCase();
+  return views.some(
+    (v) =>
+      v.online &&
+      ((!!fp && v.fp.toLowerCase() === fp) ||
+        (!!pin.host_id && v.id === pin.host_id) ||
+        (v.addr === pin.host && v.port === pin.port)),
+  );
+}
+
+/**
+ * Reset all Punktfunk state (saved hosts + stream settings + pins), keeping the client identity.
+ * Refreshes whatever views are passed so the UI clears immediately. Ends in a toast.
+ */
+export async function resetAll(refreshers: Array<() => void | Promise<void>>): Promise<void> {
+  try {
+    const r = await resetConfig();
+    for (const fn of refreshers) void fn();
+    toaster.toast({
+      title: "Punktfunk",
+      body: r.ok
+        ? "Reset — saved hosts, settings, and pins cleared."
+        : `Reset failed${r.error ? ` (${r.error})` : ""}.`,
+    });
+  } catch {
+    toaster.toast({ title: "Punktfunk", body: "Reset failed." });
+  }
+}
+
 // ----------------------------------------------------------------------------------------
 // Self-update — checks our registry on mount (the backend caches for 30 min + is non-fatal
 // offline); `check(true)` bypasses the cache for the explicit "Check for updates" button.

clients/decky/src/hostmgmt.tsx

@@ -0,0 +1,164 @@
+// Add / edit host dialogs for the fullscreen page. These mutate the SHARED known-hosts store
+// (client-known-hosts.json) through the flatpak client's headless modes, so a host saved or
+// renamed here shows up in the desktop client too. Text entry uses @decky/ui's TextField, which
+// brings up Steam's on-screen keyboard on focus (the digit-grid trick in pair.tsx is only needed
+// for the numeric PIN).
+import { DialogButton, Focusable, ModalRoot, Spinner, TextField } from "@decky/ui";
+import { toaster } from "@decky/api";
+import { ChangeEvent, FC, useState } from "react";
+import { addHost, editHost, MutationResult } from "./backend";
+import { HostView } from "./hooks";
+import { actionButton } from "./ui";
+
+/** Stable copy for a failed host-store mutation. */
+export function mutationError(r: MutationResult): string {
+  switch (r.error) {
+    case "client-unavailable":
+      return "The Punktfunk client isn't installed (flatpak io.unom.Punktfunk).";
+    case "client-outdated":
+      return "The installed client is too old for host management — update it from the About tab.";
+    default:
+      return r.detail || "Couldn't save the host.";
+  }
+}
+
+// Split a typed address: a pasted `host:port` wins over the separate port field. IPv6 literals
+// aren't supported by the host advert/known-hosts format, so a bare colon is treated as host:port.
+function targetFrom(addr: string, port: string): string {
+  const a = addr.trim();
+  if (a.includes(":")) {
+    return a;
+  }
+  const p = port.trim() || "9777";
+  return `${a}:${p}`;
+}
+
+const field: React.CSSProperties = { marginBottom: "0.8em" };
+
+const HostForm: FC<{
+  title: string;
+  submitLabel: string;
+  initial: { addr: string; port: string; name: string };
+  addrDisabled?: boolean;
+  onSubmit: (addr: string, port: string, name: string) => Promise<MutationResult>;
+  onDone: () => void;
+  closeModal?: () => void;
+}> = ({ title, submitLabel, initial, addrDisabled, onSubmit, onDone, closeModal }) => {
+  const [addr, setAddr] = useState(initial.addr);
+  const [port, setPort] = useState(initial.port);
+  const [name, setName] = useState(initial.name);
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const submit = async () => {
+    if (!addr.trim()) {
+      setError("Enter an address.");
+      return;
+    }
+    setBusy(true);
+    setError(null);
+    try {
+      const r = await onSubmit(addr.trim(), port.trim(), name.trim());
+      if (r.ok) {
+        onDone();
+        closeModal?.();
+      } else {
+        setError(mutationError(r));
+      }
+    } catch (e) {
+      setError(String(e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  return (
+    <ModalRoot closeModal={closeModal}>
+      <div style={{ fontWeight: "bold", fontSize: "1.3em", marginBottom: "0.6em" }}>{title}</div>
+      <div style={field}>
+        <TextField
+          label="Address"
+          description="IP or hostname (a Tailscale/VPN name works too). Add :port to override."
+          value={addr}
+          disabled={addrDisabled || busy}
+          onChange={(e: ChangeEvent<HTMLInputElement>) => setAddr(e.target.value)}
+        />
+      </div>
+      <div style={field}>
+        <TextField
+          label="Port"
+          value={port}
+          mustBeNumeric
+          disabled={busy}
+          onChange={(e: ChangeEvent<HTMLInputElement>) => setPort(e.target.value)}
+        />
+      </div>
+      <div style={field}>
+        <TextField
+          label="Name (optional)"
+          value={name}
+          disabled={busy}
+          onChange={(e: ChangeEvent<HTMLInputElement>) => setName(e.target.value)}
+        />
+      </div>
+      {error && (
+        <div style={{ color: "#ff6b6b", marginBottom: "0.6em" }}>{error}</div>
+      )}
+      <Focusable style={{ display: "flex", gap: "0.5em", justifyContent: "flex-end" }}>
+        <DialogButton style={actionButton} disabled={busy} onClick={() => closeModal?.()}>
+          Cancel
+        </DialogButton>
+        <DialogButton style={actionButton} disabled={busy} onClick={submit}>
+          {busy ? <Spinner style={{ height: "1em" }} /> : submitLabel}
+        </DialogButton>
+      </Focusable>
+    </ModalRoot>
+  );
+};
+
+/** "+" — save a new host by address (unpaired placeholder; the user pairs it next). */
+export const AddHostModal: FC<{ onDone: () => void; closeModal?: () => void }> = ({
+  onDone,
+  closeModal,
+}) => (
+  <HostForm
+    title="Add host"
+    submitLabel="Add"
+    initial={{ addr: "", port: "9777", name: "" }}
+    onSubmit={async (addr, port, name) => {
+      const r = await addHost(targetFrom(addr, port), name, "");
+      if (r.ok) {
+        toaster.toast({ title: "Punktfunk", body: `Added ${name || addr}` });
+      }
+      return r;
+    }}
+    onDone={onDone}
+    closeModal={closeModal}
+  />
+);
+
+/** Rename / re-point a saved host. Identified by fingerprint when it has one (survives IP
+ *  changes), else by its current address. */
+export const EditHostModal: FC<{
+  host: HostView;
+  onDone: () => void;
+  closeModal?: () => void;
+}> = ({ host, onDone, closeModal }) => {
+  const selector = host.fp || `${host.addr}:${host.port}`;
+  return (
+    <HostForm
+      title={`Edit ${host.name}`}
+      submitLabel="Save"
+      initial={{ addr: host.addr, port: String(host.port), name: host.name }}
+      onSubmit={async (addr, port, name) => {
+        const r = await editHost(selector, name, addr, parseInt(port, 10) || 0);
+        if (r.ok) {
+          toaster.toast({ title: "Punktfunk", body: `Updated ${name || addr}` });
+        }
+        return r;
+      }}
+      onDone={onDone}
+      closeModal={closeModal}
+    />
+  );
+};

clients/decky/src/index.tsx

@@ -18,10 +18,14 @@ import {
   applyUpdate,
   checkForUpdatesNow,
   hasUpdate,
-  resolvePinHost,
+  mergeHosts,
+  needsPair,
+  pinIsOnline,
   startStream,
+  toHost,
   useHosts,
   usePins,
+  useSavedHosts,
   useUpdate,
 } from "./hooks";
 import { streamPin } from "./library";
@@ -33,10 +37,18 @@ import { PairModal } from "./pair";
 // and pinned games.
 // ----------------------------------------------------------------------------------------
 const QamPanel: FC = () => {
-  const { hosts, scanning, refresh } = useHosts();
+  const { hosts: discovered, scanning, refresh: refreshDiscovered } = useHosts();
+  const { saved, loading: loadingSaved, refresh: refreshSaved } = useSavedHosts();
   const { info: update, checking, check } = useUpdate();
   const pins = usePins();
 
+  const hosts = mergeHosts(saved, discovered);
+  const busy = scanning || loadingSaved;
+  const refresh = () => {
+    void refreshDiscovered();
+    void refreshSaved();
+  };
+
   return (
     <>
       {hasUpdate(update) && (
@@ -82,12 +94,12 @@ const QamPanel: FC = () => {
       {pins.pins.length > 0 && (
         <PanelSection title="Pinned Games">
           {pins.pins.map((pin) => {
-            const { online } = resolvePinHost(pin, hosts);
+            const online = pinIsOnline(pin, hosts);
             return (
               <PanelSectionRow key={`${pin.host_fp}:${pin.game_id}`}>
                 <ButtonItem
                   layout="below"
-                  onClick={() => streamPin(pin, hosts, pins)}
+                  onClick={() => streamPin(pin, hosts.map(toHost), pins)}
                   label={pin.title}
                   description={`${pin.host_name}${online ? "" : " · offline?"}${
                     pin.paired ? "" : " · pairing required"
@@ -104,49 +116,52 @@ const QamPanel: FC = () => {
 
       <PanelSection title="Hosts">
         <PanelSectionRow>
-          <ButtonItem layout="below" onClick={refresh} disabled={scanning}>
-            {scanning ? (
+          <ButtonItem layout="below" onClick={refresh} disabled={busy}>
+            {busy ? (
               <Spinner style={{ height: "1em", marginRight: "0.5em" }} />
             ) : (
               <FaSyncAlt style={{ marginRight: "0.5em" }} />
             )}
-            {scanning ? "Scanning…" : "Refresh"}
+            {busy ? "Scanning…" : "Refresh"}
           </ButtonItem>
         </PanelSectionRow>
-        {hosts.length === 0 && scanning && (
+        {hosts.length === 0 && busy && (
           <PanelSectionRow>
             <Field focusable={false} description="Scanning your network…" />
           </PanelSectionRow>
         )}
-        {hosts.length === 0 && !scanning && (
+        {hosts.length === 0 && !busy && (
           <PanelSectionRow>
             <Field
               focusable={false}
               label="No hosts found"
-              description="Start a Punktfunk host on this network, then refresh."
+              description="Open Punktfunk to add a host by address, or start a host on this network and refresh."
             />
           </PanelSectionRow>
         )}
-        {hosts.map((h) => {
-          const needsPair = h.pair === "required" && !h.paired;
+        {hosts.map((v) => {
+          const pair = needsPair(v);
+          const h = toHost(v);
           return (
-            <PanelSectionRow key={h.fp || `${h.host}:${h.port}`}>
+            <PanelSectionRow key={v.fp || `${v.addr}:${v.port}`}>
               <ButtonItem
                 layout="below"
                 onClick={() =>
-                  needsPair
+                  pair
                     ? showModal(<PairModal host={h} onPaired={() => startStream(h)} />)
                     : startStream(h)
                 }
                 label={
                   <span style={{ display: "inline-flex", alignItems: "center", gap: "0.4em" }}>
-                    {needsPair ? <FaLock /> : <FaLockOpen />}
-                    {h.name}
+                    {pair ? <FaLock /> : <FaLockOpen />}
+                    {v.name}
                   </span>
                 }
-                description={`${h.host}:${h.port}${h.paired ? " · paired" : ""}`}
+                description={`${v.addr}:${v.port} · ${v.online ? "online" : "offline"}${
+                  pair ? " · pairing required" : v.paired ? " · paired" : ""
+                }`}
               >
-                {needsPair ? "Pair & Stream" : "Stream"}
+                {pair ? "Pair & Stream" : "Stream"}
               </ButtonItem>
             </PanelSectionRow>
           );

clients/decky/src/page.tsx

@@ -1,5 +1,6 @@
 // The fullscreen page (registered as the /punktfunk route) — Hosts / Settings / About tabs.
 import {
+  ConfirmModal,
   DialogButton,
   Field,
   Focusable,
@@ -20,24 +21,34 @@ import {
   FaInfoCircle,
   FaLock,
   FaLockOpen,
+  FaPen,
   FaPlay,
+  FaPlus,
   FaSyncAlt,
   FaThLarge,
+  FaTrashAlt,
 } from "react-icons/fa";
-import { Host, UpdateInfo, killStream } from "./backend";
+import { UpdateInfo, forgetHost, killStream } from "./backend";
 import { PluginErrorBoundary } from "./boundary";
 import {
   DOCS_URL,
+  HostView,
   PinsApi,
   applyUpdate,
   checkForUpdatesNow,
   hasUpdate,
-  resolvePinHost,
+  mergeHosts,
+  needsPair,
+  pinIsOnline,
+  resetAll,
   startStream,
+  toHost,
   useHosts,
   usePins,
+  useSavedHosts,
   useUpdate,
 } from "./hooks";
+import { AddHostModal, EditHostModal, mutationError } from "./hostmgmt";
 import { GamePickerModal, storeLabel, streamPin } from "./library";
 import { PairModal } from "./pair";
 import { SettingsSection } from "./settings";
@@ -59,31 +70,62 @@ const tabScroll: CSSProperties = {
   boxSizing: "border-box",
 };
 
+// The one-line status under a host name: address, live presence, and trust state.
+function hostSubtitle(v: HostView): string {
+  const parts = [`${v.addr}:${v.port}`, v.online ? "online" : "offline"];
+  if (needsPair(v)) {
+    parts.push("pairing required");
+  } else if (v.paired) {
+    parts.push("paired");
+  } else if (v.saved) {
+    parts.push("trusted");
+  }
+  return parts.join(" · ");
+}
+
+/** Confirm + forget a saved host, then refresh the list. */
+function confirmForget(v: HostView, refresh: () => void): void {
+  const selector = v.fp || `${v.addr}:${v.port}`;
+  showModal(
+    <ConfirmModal
+      strTitle={`Forget ${v.name}?`}
+      strDescription="You'll need to pair or trust it again to reconnect."
+      strOKButtonText="Forget"
+      bDestructiveWarning
+      onOK={async () => {
+        const r = await forgetHost(selector);
+        toaster.toast({
+          title: "Punktfunk",
+          body: r.ok ? `Forgot ${v.name}` : mutationError(r),
+        });
+        refresh();
+      }}
+    />,
+  );
+}
+
 // ----------------------------------------------------------------------------------------
-// Host details — everything the mDNS advert told us, incl. the fingerprint to cross-check
-// against the host's own log / web console before trusting it.
+// Host details — everything we know, plus (for a saved host) rename / edit / forget.
 // ----------------------------------------------------------------------------------------
-const HostDetailsModal: FC<{ host: Host; closeModal?: () => void }> = ({
-  host,
-  closeModal,
-}) => {
-  const fp = host.fp ? (host.fp.match(/.{1,4}/g) ?? [host.fp]).join(" ") : "not advertised";
+const HostDetailsModal: FC<{
+  host: HostView;
+  onChanged: () => void;
+  closeModal?: () => void;
+}> = ({ host, onChanged, closeModal }) => {
+  const fp = host.fp ? (host.fp.match(/.{1,4}/g) ?? [host.fp]).join(" ") : "not known yet";
   return (
     <ModalRoot closeModal={closeModal}>
       <div style={{ fontWeight: "bold", fontSize: "1.3em", marginBottom: "0.4em" }}>
         {host.name}
       </div>
       <Field focusable={false} label="Address">
-        {host.host}:{host.port}
+        {host.addr}:{host.port}
       </Field>
-      <Field focusable={false} label="Protocol">
-        {host.proto || "unknown"}
-      </Field>
-      <Field focusable={false} label="Pairing policy">
-        {host.pair === "required" ? "PIN pairing required" : "Open (trust on first connect)"}
+      <Field focusable={false} label="Presence">
+        {host.online ? "Online" : "Offline"}
       </Field>
       <Field focusable={false} label="This Deck">
-        {host.paired ? "Paired" : "Not paired yet"}
+        {host.paired ? "Paired" : host.fp ? "Trusted" : "Not paired yet"}
       </Field>
       <Field
         focusable={false}
@@ -96,6 +138,32 @@ const HostDetailsModal: FC<{ host: Host; closeModal?: () => void }> = ({
           </span>
         }
       />
+      {host.saved && (
+        <Field label="Manage" childrenContainerWidth="max">
+          <RowActions>
+            <DialogButton
+              style={actionButton}
+              onClick={() => {
+                closeModal?.();
+                showModal(<EditHostModal host={host} onDone={onChanged} />);
+              }}
+            >
+              <FaPen style={{ marginRight: "0.4em" }} />
+              Edit
+            </DialogButton>
+            <DialogButton
+              style={actionButton}
+              onClick={() => {
+                closeModal?.();
+                confirmForget(host, onChanged);
+              }}
+            >
+              <FaTrashAlt style={{ marginRight: "0.4em" }} />
+              Forget
+            </DialogButton>
+          </RowActions>
+        </Field>
+      )}
     </ModalRoot>
   );
 };
@@ -103,31 +171,28 @@ const HostDetailsModal: FC<{ host: Host; closeModal?: () => void }> = ({
 // ----------------------------------------------------------------------------------------
 // One host row: status icon + address, details / pair / stream actions.
 // ----------------------------------------------------------------------------------------
-const HostRow: FC<{ host: Host; onPaired: () => void; onGames: () => void }> = ({
-  host,
-  onPaired,
-  onGames,
-}) => {
-  // The host's policy is `pair=required`, but if THIS device is already paired we don't need to
-  // pair again — show it as trusted and go straight to Stream.
-  const needsPair = host.pair === "required" && !host.paired;
+const HostRow: FC<{
+  host: HostView;
+  onChanged: () => void;
+  onGames: () => void;
+}> = ({ host, onChanged, onGames }) => {
+  const pair = needsPair(host);
+  const h = toHost(host);
   return (
     <Field
       label={
         <span style={{ display: "inline-flex", alignItems: "center", gap: "0.4em" }}>
-          {needsPair ? <FaLock /> : <FaLockOpen />}
+          {pair ? <FaLock /> : <FaLockOpen />}
           {host.name}
         </span>
       }
-      description={`${host.host}:${host.port}${
-        needsPair ? " · pairing required" : host.paired ? " · paired" : ""
-      }`}
+      description={hostSubtitle(host)}
       childrenContainerWidth="max"
     >
       <RowActions>
         <DialogButton
           style={iconButton}
-          onClick={() => showModal(<HostDetailsModal host={host} />)}
+          onClick={() => showModal(<HostDetailsModal host={host} onChanged={onChanged} />)}
         >
           <FaInfoCircle />
         </DialogButton>
@@ -137,10 +202,10 @@ const HostRow: FC<{ host: Host; onPaired: () => void; onGames: () => void }> = (
           <FaThLarge style={{ marginRight: "0.4em" }} />
           Games
         </DialogButton>
-        {needsPair && (
+        {pair && (
           <DialogButton
             style={actionButton}
-            onClick={() => showModal(<PairModal host={host} onPaired={onPaired} />)}
+            onClick={() => showModal(<PairModal host={h} onPaired={onChanged} />)}
           >
             Pair
           </DialogButton>
@@ -148,11 +213,9 @@ const HostRow: FC<{ host: Host; onPaired: () => void; onGames: () => void }> = (
         <DialogButton
           style={actionButton}
           onClick={() =>
-            needsPair
-              ? showModal(
-                  <PairModal host={host} onPaired={() => startStream(host)} />,
-                )
-              : startStream(host)
+            pair
+              ? showModal(<PairModal host={h} onPaired={() => startStream(h)} />)
+              : startStream(h)
           }
         >
           <FaPlay style={{ marginRight: "0.4em" }} />
@@ -164,7 +227,7 @@ const HostRow: FC<{ host: Host; onPaired: () => void; onGames: () => void }> = (
 };
 
 const HostsTab: FC<{
-  hosts: Host[];
+  hosts: HostView[];
   scanning: boolean;
   refresh: () => void;
   pins: PinsApi;
@@ -172,16 +235,23 @@ const HostsTab: FC<{
 }> = ({ hosts, scanning, refresh, pins, clientUpdatePending }) => (
   <div style={tabScroll}>
     <Field
-      label="Discover"
+      label="Hosts"
       description={
         scanning
           ? "Scanning the LAN…"
-          : `${hosts.length} host${hosts.length === 1 ? "" : "s"} on your network`
+          : `${hosts.length} host${hosts.length === 1 ? "" : "s"} — saved and on your network`
       }
       childrenContainerWidth="max"
       bottomSeparator={hosts.length ? "standard" : "none"}
     >
       <RowActions>
+        <DialogButton
+          style={actionButton}
+          onClick={() => showModal(<AddHostModal onDone={refresh} />)}
+        >
+          <FaPlus style={{ marginRight: "0.5em" }} />
+          Add
+        </DialogButton>
         <DialogButton style={actionButton} disabled={scanning} onClick={refresh}>
           {scanning ? (
             <Spinner style={{ height: "1em", marginRight: "0.5em" }} />
@@ -196,18 +266,22 @@ const HostsTab: FC<{
     {hosts.length === 0 && !scanning && (
       <Field
         focusable={false}
-        label="No hosts found"
-        description="Start a Punktfunk host on the same network, then refresh. The setup guide (About tab) covers installing a host."
+        label="No hosts yet"
+        description="Add one by address with +, or start a Punktfunk host on this network and refresh. The setup guide (About tab) covers installing a host."
       />
     )}
     {hosts.map((h) => (
       <HostRow
-        key={h.fp || `${h.host}:${h.port}`}
+        key={h.fp || `${h.addr}:${h.port}`}
         host={h}
-        onPaired={refresh}
+        onChanged={refresh}
         onGames={() =>
           showModal(
-            <GamePickerModal host={h} pins={pins} clientUpdatePending={clientUpdatePending} />,
+            <GamePickerModal
+              host={toHost(h)}
+              pins={pins}
+              clientUpdatePending={clientUpdatePending}
+            />,
           )
         }
       />
@@ -223,7 +297,7 @@ const HostsTab: FC<{
           bottomSeparator="standard"
         />
         {pins.pins.map((pin) => {
-          const { online } = resolvePinHost(pin, hosts);
+          const online = pinIsOnline(pin, hosts);
           return (
             <Field
               key={`${pin.host_fp}:${pin.game_id}`}
@@ -234,7 +308,10 @@ const HostsTab: FC<{
               childrenContainerWidth="max"
             >
               <RowActions>
-                <DialogButton style={actionButton} onClick={() => streamPin(pin, hosts, pins)}>
+                <DialogButton
+                  style={actionButton}
+                  onClick={() => streamPin(pin, hosts.map(toHost), pins)}
+                >
                   <FaPlay style={{ marginRight: "0.4em" }} />
                   Play
                 </DialogButton>
@@ -260,7 +337,8 @@ const SettingsTab: FC = () => (
 );
 
 // ----------------------------------------------------------------------------------------
-// About — plugin version + explicit update check, docs link, stream-exit help, force-stop.
+// About — plugin version + explicit update check, docs link, stream-exit help, force-stop,
+// and the destructive "reset everything" action.
 // ----------------------------------------------------------------------------------------
 async function forceStopStream(): Promise<void> {
   stopStream(); // ask Steam to end the "game" first (clean path)
@@ -271,11 +349,24 @@ async function forceStopStream(): Promise<void> {
   });
 }
 
+function confirmReset(refreshers: Array<() => void | Promise<void>>): void {
+  showModal(
+    <ConfirmModal
+      strTitle="Reset Punktfunk?"
+      strDescription="Clears every saved host, your stream settings, and all pinned games on this Deck. Your client identity is kept, so you'll re-pair hosts to reconnect. This can't be undone."
+      strOKButtonText="Reset"
+      bDestructiveWarning
+      onOK={() => void resetAll(refreshers)}
+    />,
+  );
+}
+
 const AboutTab: FC<{
   update: UpdateInfo | null;
   checking: boolean;
   check: (force: boolean) => Promise<UpdateInfo | null>;
-}> = ({ update, checking, check }) => (
+  onReset: () => void;
+}> = ({ update, checking, check, onReset }) => (
   <div style={tabScroll}>
     <Field
       label="Version"
@@ -349,15 +440,35 @@ const AboutTab: FC<{
         </DialogButton>
       </RowActions>
     </Field>
+    <Field
+      label="Reset Punktfunk"
+      description="Clear saved hosts, stream settings, and pinned games on this Deck (keeps your client identity)"
+      childrenContainerWidth="max"
+    >
+      <RowActions>
+        <DialogButton style={actionButton} onClick={onReset}>
+          <FaTrashAlt style={{ marginRight: "0.4em" }} />
+          Reset
+        </DialogButton>
+      </RowActions>
+    </Field>
   </div>
 );
 
 const PunktfunkPage: FC = () => {
-  const { hosts, scanning, refresh } = useHosts();
+  const { hosts: discovered, scanning, refresh: refreshDiscovered } = useHosts();
+  const { saved, loading: loadingSaved, refresh: refreshSaved } = useSavedHosts();
   const { info: update, checking, check } = useUpdate();
   const pins = usePins();
   const [tab, setTab] = useState("hosts");
 
+  const hosts = mergeHosts(saved, discovered);
+  // A host action (pair/add/edit/forget) can change either store, so refresh both.
+  const refreshHosts = () => {
+    void refreshDiscovered();
+    void refreshSaved();
+  };
+
   return (
     <div
       style={{
@@ -408,8 +519,8 @@ const PunktfunkPage: FC = () => {
               content: (
                 <HostsTab
                   hosts={hosts}
-                  scanning={scanning}
-                  refresh={refresh}
+                  scanning={scanning || loadingSaved}
+                  refresh={refreshHosts}
                   pins={pins}
                   clientUpdatePending={!!update?.client_update_available}
                 />
@@ -423,7 +534,14 @@ const PunktfunkPage: FC = () => {
             {
               id: "about",
               title: "About",
-              content: <AboutTab update={update} checking={checking} check={check} />,
+              content: (
+                <AboutTab
+                  update={update}
+                  checking={checking}
+                  check={check}
+                  onReset={() => confirmReset([refreshHosts, pins.refresh])}
+                />
+              ),
             },
           ]}
         />

clients/linux/src/app.rs

@@ -583,6 +583,11 @@ pub fn run() -> glib::ExitCode {
     if crate::cli::arg_value("--wake").is_some() {
         return crate::cli::cli_wake();
     }
+    // Headless known-hosts management (list/add/edit/forget/reset) + reachability probes —
+    // the shared store the Decky plugin drives; returns None when argv names none of them.
+    if let Some(code) = crate::cli::headless_host_command() {
+        return code;
+    }
     // Streams and the console library live in the session binary now — exec it,
     // forwarding the relevant argv (the Decky wrapper keeps working through the shell
     // until it's repointed).

clients/linux/src/cli.rs

@@ -3,12 +3,15 @@
 //! scenes.
 
 use crate::app::AppModel;
+use crate::trust::{KnownHost, KnownHosts};
 use crate::ui_hosts::{ConnectRequest, HostsMsg};
 use gtk::glib;
 use gtk::prelude::*;
+use punktfunk_core::client::NativeClient;
 use relm4::prelude::*;
 use std::cell::RefCell;
 use std::rc::Rc;
+use std::time::Duration;
 
 /// The handles `run_shot` needs — cloned out of `AppModel` before it moves into the
 /// component parts, so the scene can be dispatched from the window's `map` callback.
@@ -116,6 +119,11 @@ pub fn headless_pair(pin: &str) -> glib::ExitCode {
                 &fp_hex,
                 true,
             );
+            // A host manually added via `--add-host` (no fingerprint yet) is stored as an
+            // addr-keyed placeholder; now that the ceremony yielded the real fingerprint,
+            // `persist_host` created the fp-keyed entry — drop the placeholder so the list
+            // shows this host once, not twice.
+            forget_placeholder(&addr, port);
             println!("paired {addr}:{port} fp={fp_hex}");
             glib::ExitCode::SUCCESS
         }
@@ -194,6 +202,274 @@ pub fn headless_library(target: &str) -> glib::ExitCode {
     }
 }
 
+// -----------------------------------------------------------------------------------------
+// Headless host-store management — the shared known-hosts store (`client-known-hosts.json`)
+// is the SINGLE source of truth for every client on this device (the GTK shell, the Vulkan
+// session, and the Decky plugin, which shells out to these modes). Exposing add/edit/forget/
+// list/reset here lets the Decky Gaming-Mode UI mutate exactly the store the desktop client
+// reads, so a change in one surface shows up in the other. Reachability (`--list-hosts
+// --probe`, `--reachable`) answers "is this host online?" WITHOUT mDNS, so a host reached
+// over a routed network (Tailscale/VPN/another subnet) no longer reads as offline.
+// -----------------------------------------------------------------------------------------
+
+/// The per-probe budget: a cold host on a routed link answers in well under this, and every
+/// saved host is probed in parallel so the wall-clock cost is one timeout, not the sum.
+const PROBE_TIMEOUT: Duration = Duration::from_millis(2500);
+
+/// Selector for `--set-host`/`--forget-host`: a 64-hex fingerprint pins one entry across IP
+/// changes; anything else is treated as `addr[:port]` (manual entries have no fingerprint).
+enum Selector {
+    Fp(String),
+    Addr(String, u16),
+}
+
+fn parse_selector(s: &str) -> Selector {
+    if s.len() == 64 && s.bytes().all(|b| b.is_ascii_hexdigit()) {
+        Selector::Fp(s.to_lowercase())
+    } else {
+        let (addr, port) = parse_host_port(s);
+        Selector::Addr(addr, port.unwrap_or(9777))
+    }
+}
+
+impl Selector {
+    fn matches(&self, h: &KnownHost) -> bool {
+        match self {
+            Selector::Fp(fp) => h.fp_hex.eq_ignore_ascii_case(fp),
+            Selector::Addr(addr, port) => h.addr == *addr && h.port == *port,
+        }
+    }
+}
+
+/// Probe every saved host for reachability in parallel (shared with the hosts-page presence pips).
+fn probe_all(hosts: &[KnownHost]) -> Vec<bool> {
+    crate::trust::probe_reachable_many(
+        hosts.iter().map(|h| (h.addr.clone(), h.port)).collect(),
+        PROBE_TIMEOUT,
+    )
+}
+
+/// Drop an fp-less placeholder for `addr:port` (see `headless_pair`). No-op when none exists.
+fn forget_placeholder(addr: &str, port: u16) {
+    let mut known = KnownHosts::load();
+    let before = known.hosts.len();
+    known
+        .hosts
+        .retain(|h| !(h.fp_hex.is_empty() && h.addr == addr && h.port == port));
+    if known.hosts.len() != before {
+        let _ = known.save();
+    }
+}
+
+/// `--list-hosts [--probe]` — the saved known-hosts store as JSON (the store the Decky plugin
+/// renders). With `--probe`, each host carries an `online` bool from a live reachability probe
+/// (mDNS-independent); without it, `online` is `null` (unknown — the caller falls back to its
+/// own mDNS view). Shape: `{"hosts":[{name,addr,port,fp_hex,paired,mac,last_used,online}]}`.
+pub fn headless_list_hosts() -> glib::ExitCode {
+    let known = KnownHosts::load();
+    let online: Option<Vec<bool>> = arg_flag("--probe").then(|| probe_all(&known.hosts));
+    let hosts: Vec<serde_json::Value> = known
+        .hosts
+        .iter()
+        .enumerate()
+        .map(|(i, h)| {
+            serde_json::json!({
+                "name": h.name,
+                "addr": h.addr,
+                "port": h.port,
+                "fp_hex": h.fp_hex,
+                "paired": h.paired,
+                "mac": h.mac,
+                "last_used": h.last_used,
+                "online": online.as_ref().map(|v| serde_json::Value::Bool(v[i]))
+                    .unwrap_or(serde_json::Value::Null),
+            })
+        })
+        .collect();
+    match serde_json::to_string(&serde_json::json!({ "hosts": hosts })) {
+        Ok(s) => {
+            println!("{s}");
+            glib::ExitCode::SUCCESS
+        }
+        Err(e) => {
+            eprintln!("list-hosts: {e}");
+            glib::ExitCode::FAILURE
+        }
+    }
+}
+
+/// `--reachable host[:port]` — probe one target and exit 0 (reachable) / 1 (not). A cheap
+/// "is it online / test this address" check that never touches mDNS.
+pub fn headless_reachable(target: &str) -> glib::ExitCode {
+    let (addr, port) = parse_host_port(target);
+    let port = port.unwrap_or(9777);
+    if NativeClient::probe(&addr, port, PROBE_TIMEOUT) {
+        println!("reachable {addr}:{port}");
+        glib::ExitCode::SUCCESS
+    } else {
+        eprintln!("unreachable {addr}:{port}");
+        glib::ExitCode::FAILURE
+    }
+}
+
+/// `--add-host host[:port] [--host-label NAME] [--fp HEX]` — save a host by address so it can
+/// be paired/streamed even when mDNS never sees it (a Tailscale/VPN box). Without `--fp` the
+/// entry is an unpaired placeholder (keyed by address) the user pairs later — `headless_pair`
+/// then replaces it with the fingerprinted entry. With `--fp` (e.g. carried from an advert)
+/// it is pinned immediately as trusted-but-not-PIN-paired. Prints `added <addr>:<port>`.
+pub fn headless_add_host(target: &str) -> glib::ExitCode {
+    let (addr, port) = parse_host_port(target);
+    let port = port.unwrap_or(9777);
+    let name = arg_value("--host-label")
+        .map(|n| n.trim().to_string())
+        .filter(|n| !n.is_empty())
+        .unwrap_or_else(|| addr.clone());
+    if let Some(fp_hex) = arg_value("--fp").filter(|f| crate::trust::parse_hex32(f).is_some()) {
+        // Fingerprint known up front: upsert the pinned entry (paired stays false — no PIN
+        // ceremony happened; a later `--pair` upgrades it).
+        crate::trust::persist_host(&name, &addr, port, &fp_hex.to_lowercase(), false);
+        forget_placeholder(&addr, port);
+        println!("added {addr}:{port} fp={}", fp_hex.to_lowercase());
+        return glib::ExitCode::SUCCESS;
+    }
+    // No fingerprint yet — an address-keyed placeholder. Refresh the name if it already exists.
+    let mut known = KnownHosts::load();
+    if let Some(h) = known
+        .hosts
+        .iter_mut()
+        .find(|h| h.addr == addr && h.port == port)
+    {
+        h.name = name;
+    } else {
+        known.hosts.push(KnownHost {
+            name,
+            addr: addr.clone(),
+            port,
+            fp_hex: String::new(),
+            paired: false,
+            last_used: None,
+            mac: Vec::new(),
+        });
+    }
+    match known.save() {
+        Ok(()) => {
+            println!("added {addr}:{port}");
+            glib::ExitCode::SUCCESS
+        }
+        Err(e) => {
+            eprintln!("add-host: {e:#}");
+            glib::ExitCode::FAILURE
+        }
+    }
+}
+
+/// `--set-host <fp|host[:port]> [--host-label NAME] [--addr ADDR] [--port PORT]` — edit a saved
+/// host: rename and/or re-point its address. Identified by fingerprint (survives IP changes) or
+/// current address. Prints `updated <name>`; fails if nothing matched.
+pub fn headless_set_host(selector: &str) -> glib::ExitCode {
+    let sel = parse_selector(selector);
+    let mut known = KnownHosts::load();
+    let Some(h) = known.hosts.iter_mut().find(|h| sel.matches(h)) else {
+        eprintln!("set-host: no saved host matches {selector:?}");
+        return glib::ExitCode::FAILURE;
+    };
+    if let Some(name) = arg_value("--host-label").map(|n| n.trim().to_string()) {
+        if !name.is_empty() {
+            h.name = name;
+        }
+    }
+    if let Some(addr) = arg_value("--addr").map(|a| a.trim().to_string()) {
+        if !addr.is_empty() {
+            h.addr = addr;
+        }
+    }
+    if let Some(port) = arg_value("--port").and_then(|p| p.trim().parse::<u16>().ok()) {
+        h.port = port;
+    }
+    let label = h.name.clone();
+    match known.save() {
+        Ok(()) => {
+            println!("updated {label}");
+            glib::ExitCode::SUCCESS
+        }
+        Err(e) => {
+            eprintln!("set-host: {e:#}");
+            glib::ExitCode::FAILURE
+        }
+    }
+}
+
+/// `--forget-host <fp|host[:port]>` — remove a saved host (drops the pinned fingerprint; a later
+/// connect must re-pair/trust). Prints `forgot N`; succeeds even if nothing matched (idempotent).
+pub fn headless_forget_host(selector: &str) -> glib::ExitCode {
+    let sel = parse_selector(selector);
+    let mut known = KnownHosts::load();
+    let before = known.hosts.len();
+    known.hosts.retain(|h| !sel.matches(h));
+    let removed = before - known.hosts.len();
+    if removed > 0 {
+        if let Err(e) = known.save() {
+            eprintln!("forget-host: {e:#}");
+            return glib::ExitCode::FAILURE;
+        }
+    }
+    println!("forgot {removed}");
+    glib::ExitCode::SUCCESS
+}
+
+/// `--reset` — clear this device's client state: the saved known-hosts and the stream
+/// settings. The persistent IDENTITY (`client-cert.pem`/`client-key.pem`) is deliberately
+/// KEPT so the box isn't seen as a brand-new device everywhere (a re-pair still re-adds hosts);
+/// a caller wanting a true factory reset removes those separately. Missing files are fine.
+pub fn headless_reset() -> glib::ExitCode {
+    let Ok(dir) = crate::trust::config_dir() else {
+        eprintln!("reset: could not resolve config dir (HOME unset?)");
+        return glib::ExitCode::FAILURE;
+    };
+    let mut ok = true;
+    for name in ["client-known-hosts.json", "client-gtk-settings.json"] {
+        match std::fs::remove_file(dir.join(name)) {
+            Ok(()) => {}
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {}
+            Err(e) => {
+                eprintln!("reset: {name}: {e}");
+                ok = false;
+            }
+        }
+    }
+    if ok {
+        println!("reset");
+        glib::ExitCode::SUCCESS
+    } else {
+        glib::ExitCode::FAILURE
+    }
+}
+
+/// Dispatch the headless host-store modes (returns `None` when argv names none of them, so the
+/// caller proceeds to launch the GTK app). Kept in one place so `arg_flag` stays private and the
+/// dispatch in `app.rs` is a single line.
+pub fn headless_host_command() -> Option<glib::ExitCode> {
+    if arg_flag("--list-hosts") {
+        return Some(headless_list_hosts());
+    }
+    if let Some(t) = arg_value("--reachable") {
+        return Some(headless_reachable(&t));
+    }
+    if let Some(t) = arg_value("--add-host") {
+        return Some(headless_add_host(&t));
+    }
+    if let Some(s) = arg_value("--set-host") {
+        return Some(headless_set_host(&s));
+    }
+    if let Some(s) = arg_value("--forget-host") {
+        return Some(headless_forget_host(&s));
+    }
+    if arg_flag("--reset") {
+        return Some(headless_reset());
+    }
+    None
+}
+
 /// `PUNKTFUNK_SHOT_SCENE`, when set, selects a scripted host-free scene for CI screenshots.
 pub fn shot_scene() -> Option<String> {
     std::env::var("PUNKTFUNK_SHOT_SCENE")

clients/linux/src/ui_hosts.rs

@@ -333,8 +333,27 @@ impl relm4::factory::FactoryComponent for HostCard {
 
 // --- The page component ---------------------------------------------------------------------
 
+/// How long each saved-host reachability probe waits, and how often the sweep runs. The pip
+/// reads `advertising OR probed-reachable`, so a host reached only over a routed network
+/// (Tailscale/VPN) — which never appears on mDNS — still shows Online.
+const PROBE_TIMEOUT: std::time::Duration = std::time::Duration::from_millis(2500);
+const PROBE_INTERVAL: std::time::Duration = std::time::Duration::from_secs(12);
+
+/// The key a saved host is tracked under in the probe-results map: its fingerprint (stable
+/// across IP changes) when it has one, else `addr:port` (a not-yet-paired manual entry).
+fn saved_key(h: &KnownHost) -> String {
+    if h.fp_hex.is_empty() {
+        format!("{}:{}", h.addr, h.port)
+    } else {
+        h.fp_hex.clone()
+    }
+}
+
 pub struct HostsPage {
     adverts: HashMap<String, DiscoveredHost>,
+    /// Saved hosts proven reachable by the periodic QUIC probe (mDNS-independent), keyed by
+    /// [`saved_key`]. OR'd with live-advert presence to drive the Online pip.
+    probed: HashMap<String, bool>,
     connecting: Option<String>,
     settings: Rc<RefCell<Settings>>,
     saved: FactoryVecDeque<HostCard>,
@@ -359,6 +378,8 @@ pub enum HostsMsg {
     },
     /// Reload the disk store and re-render (fresh pairings, renames, the library gate).
     Refresh,
+    /// A completed reachability sweep: saved-host key → reachable. Merged into the online pips.
+    Probed(HashMap<String, bool>),
     /// Mark the card matching `ConnectRequest::card_key` as connecting; `None` restores.
     SetConnecting(Option<String>),
     ShowError(String),
@@ -544,8 +565,50 @@ impl SimpleComponent for HostsPage {
             });
         }
 
+        // Periodic reachability sweep: a saved host reached only over a routed network
+        // (Tailscale/VPN) never advertises on mDNS, so presence can't come from the advert map
+        // alone. Each cycle probes every saved host off the main thread (bounded, trust-agnostic
+        // QUIC handshake — the display-side companion to dial-first) and feeds results back as
+        // `Probed`; the first sweep runs immediately, then every `PROBE_INTERVAL`.
+        {
+            let sender = sender.clone();
+            glib::spawn_future_local(async move {
+                loop {
+                    let entries: Vec<(String, String, u16)> = KnownHosts::load()
+                        .hosts
+                        .iter()
+                        .filter(|h| !h.addr.is_empty())
+                        .map(|h| (saved_key(h), h.addr.clone(), h.port))
+                        .collect();
+                    if !entries.is_empty() {
+                        let (tx, rx) = async_channel::bounded(1);
+                        std::thread::Builder::new()
+                            .name("punktfunk-probe".into())
+                            .spawn(move || {
+                                let targets =
+                                    entries.iter().map(|(_, a, p)| (a.clone(), *p)).collect();
+                                let results =
+                                    crate::trust::probe_reachable_many(targets, PROBE_TIMEOUT);
+                                let map: HashMap<String, bool> = entries
+                                    .into_iter()
+                                    .map(|(k, _, _)| k)
+                                    .zip(results)
+                                    .collect();
+                                let _ = tx.send_blocking(map);
+                            })
+                            .expect("spawn probe thread");
+                        if let Ok(map) = rx.recv().await {
+                            sender.input(HostsMsg::Probed(map));
+                        }
+                    }
+                    glib::timeout_future(PROBE_INTERVAL).await;
+                }
+            });
+        }
+
         let mut model = HostsPage {
             adverts: HashMap::new(),
+            probed: HashMap::new(),
             connecting: None,
             settings,
             saved,
@@ -574,6 +637,10 @@ impl SimpleComponent for HostsPage {
                 self.rebuild();
             }
             HostsMsg::Refresh => self.rebuild(),
+            HostsMsg::Probed(map) => {
+                self.probed = map;
+                self.rebuild();
+            }
             HostsMsg::SetConnecting(key) => {
                 self.connecting = key;
                 self.rebuild();
@@ -632,7 +699,9 @@ impl HostsPage {
             let mut saved = self.saved.guard();
             saved.clear();
             for k in &known.hosts {
-                let online = self.adverts.values().any(|a| matches(k, a));
+                // Online = advertising on mDNS OR proven reachable by the last probe sweep.
+                let online = self.adverts.values().any(|a| matches(k, a))
+                    || self.probed.get(&saved_key(k)).copied().unwrap_or(false);
                 // Learn this host's wake MAC(s) from its live advert while it's online.
                 if let Some(a) = self
                     .adverts

clients/windows/src/app/hosts.rs

@@ -8,6 +8,7 @@ use super::style::*;
 use super::{Screen, Svc, Target};
 use crate::discovery::DiscoveredHost;
 use crate::trust::KnownHosts;
+use std::collections::HashMap;
 use windows_reactor::*;
 
 /// Overflow-menu item labels — `on_item_clicked` reports the clicked item by its text.
@@ -36,6 +37,10 @@ const TILE_GAP: f64 = 12.0;
 pub(crate) struct HostsProps {
     pub(crate) svc: Svc,
     pub(crate) hosts: Vec<DiscoveredHost>,
+    /// Saved hosts proven reachable by the periodic QUIC probe (keyed by `fp_hex`), OR'd with
+    /// live-advert presence to drive the Online pip — so a host reached only over a routed
+    /// network (Tailscale/VPN), which never advertises on mDNS, still reads Online.
+    pub(crate) probed: HashMap<String, bool>,
     pub(crate) status: String,
     pub(crate) forget: Option<(String, String)>,
     pub(crate) rename: Option<(String, String)>,
@@ -59,6 +64,7 @@ impl PartialEq for HostsProps {
         // Setters are identity-stable; only the value fields drive re-render.
         self.svc == other.svc
             && self.hosts == other.hosts
+            && self.probed == other.probed
             && self.status == other.status
             && self.forget == other.forget
             && self.rename == other.rename
@@ -325,9 +331,13 @@ pub(crate) fn hosts_page(props: &HostsProps, cx: &mut RenderCx) -> Element {
                 pair_optional: false,
                 mac: k.mac.clone(),
             };
+            // Online = advertising on mDNS OR proven reachable by the last probe sweep (the latter
+            // covers a routed/Tailscale host that never advertises — the display companion to
+            // dial-first).
             let online = hosts
                 .iter()
-                .any(|h| h.fp_hex == k.fp_hex || (h.addr == k.addr && h.port == k.port));
+                .any(|h| h.fp_hex == k.fp_hex || (h.addr == k.addr && h.port == k.port))
+                || props.probed.get(&k.fp_hex).copied().unwrap_or(false);
             // Learn this host's wake MAC(s) from its live advert while it's online, so we can wake
             // it once it sleeps (no-op / no disk write when unchanged).
             if let Some(a) = hosts.iter().find(|h| {

clients/windows/src/app/mod.rs

@@ -36,12 +36,14 @@ mod style;
 use crate::discovery::{self, DiscoveredHost};
 use crate::gamepad::GamepadService;
 use crate::session::Stats;
-use crate::trust::Settings;
+use crate::trust::{KnownHosts, Settings};
 use hosts::HostsProps;
 use punktfunk_core::client::NativeClient;
 use speed::{SpeedProps, SpeedState};
+use std::collections::HashMap;
 use std::sync::atomic::AtomicBool;
 use std::sync::{Arc, Mutex};
+use std::time::Duration;
 use stream::StreamProps;
 use windows_reactor::*;
 
@@ -217,6 +219,9 @@ fn root(cx: &mut RenderCx, ctx: &Arc<AppCtx>) -> Element {
     let (hover, set_hover) = cx.use_async_state(Option::<String>::None);
     // Which Settings section the NavigationView shows (persists across visits this run).
     let (settings_nav, set_settings_nav) = cx.use_async_state("display".to_string());
+    // Saved-host reachability, keyed by `fp_hex`, refreshed by the probe sweep below. Root state
+    // (thread-driven → must be root to re-render — see the module docs), passed to the hosts page.
+    let (probed, set_probed) = cx.use_async_state(HashMap::<String, bool>::new());
 
     // Continuous LAN discovery (spawned once).
     cx.use_effect((), {
@@ -260,6 +265,37 @@ fn root(cx: &mut RenderCx, ctx: &Arc<AppCtx>) -> Element {
         }
     });
 
+    // Periodic reachability sweep (spawned once): a saved host reached only over a routed network
+    // (Tailscale/VPN) never advertises on mDNS, so presence can't come from the discovery stream
+    // alone. This probes every saved host (bounded, trust-agnostic QUIC handshake — one thread each
+    // so a slow/unreachable host doesn't delay the rest) and mirrors the results into root state so
+    // the tiles get them as a prop; the pip then reads `advertising OR probed-reachable` — the
+    // display-side companion to the dial-first connect fix. The compare in `call` makes idle free.
+    cx.use_effect((), {
+        let set_probed = set_probed.clone();
+        move || {
+            std::thread::Builder::new()
+                .name("pf-probe".into())
+                .spawn(move || loop {
+                    let handles: Vec<_> = KnownHosts::load()
+                        .hosts
+                        .into_iter()
+                        .filter(|h| !h.addr.is_empty())
+                        .map(|h| {
+                            std::thread::spawn(move || {
+                                (h.fp_hex, NativeClient::probe(&h.addr, h.port, Duration::from_millis(2500)))
+                            })
+                        })
+                        .collect();
+                    let map: HashMap<String, bool> =
+                        handles.into_iter().filter_map(|h| h.join().ok()).collect();
+                    set_probed.call(map);
+                    std::thread::sleep(Duration::from_secs(12));
+                })
+                .ok();
+        }
+    });
+
     // Screen-entrance animation: each navigation slides the new screen up a few px while fading it
     // in (the Windows-Settings drill-in). It's a manual tween, not a composition animation, because
     // reactor's DSL exposes no static transform/translation setter and its one-shot animations run
@@ -375,6 +411,7 @@ fn root(cx: &mut RenderCx, ctx: &Arc<AppCtx>) -> Element {
             HostsProps {
                 svc,
                 hosts,
+                probed,
                 status,
                 forget,
                 rename,

crates/pf-client-core/src/trust.rs

@@ -221,6 +221,24 @@ pub fn pair_with_host(
     )
 }
 
+/// Probe several hosts for reachability in parallel — one thread each, so the wall-clock cost is
+/// ~one `timeout`, not the sum. Each element of the returned vec corresponds by index to
+/// `targets`. Wraps the single-host [`NativeClient::probe`] (a bounded, trust-agnostic,
+/// mDNS-independent QUIC handshake); used by the hosts page's presence pips and the headless
+/// `--list-hosts --probe`.
+pub fn probe_reachable_many(
+    targets: Vec<(String, u16)>,
+    timeout: std::time::Duration,
+) -> Vec<bool> {
+    let handles: Vec<_> = targets
+        .into_iter()
+        .map(|(addr, port)| {
+            std::thread::spawn(move || NativeClient::probe(&addr, port, timeout))
+        })
+        .collect();
+    handles.into_iter().map(|h| h.join().unwrap_or(false)).collect()
+}
+
 /// App settings, persisted as JSON. Stringly-typed gamepad/compositor prefs so the file
 /// stays readable; parsed with `*Pref::from_name` at connect time.
 #[derive(Clone, Serialize, Deserialize)]

crates/punktfunk-core/src/abi.rs

@@ -1436,6 +1436,39 @@ pub unsafe extern "C" fn punktfunk_generate_identity(
     })
 }
 
+/// Reachability probe: attempt the QUIC handshake to `host:port` and report whether the host
+/// answered — trust-agnostic and mDNS-INDEPENDENT. A host reached over a routed network
+/// (Tailscale/VPN/another subnet) answers here even though it never advertises on mDNS, so the
+/// clients' saved-host "online" pips can reflect real reachability instead of LAN presence (the
+/// display-side companion to the dial-first connect fix). Returns [`PunktfunkStatus::Ok`] when
+/// reachable, [`PunktfunkStatus::Timeout`] when not (or on any connect error). Blocks up to
+/// `timeout_ms`; call off the UI thread.
+///
+/// # Safety
+/// `host` must be a NUL-terminated UTF-8 string.
+#[cfg(feature = "quic")]
+#[no_mangle]
+pub unsafe extern "C" fn punktfunk_probe(
+    host: *const std::os::raw::c_char,
+    port: u16,
+    timeout_ms: u32,
+) -> PunktfunkStatus {
+    guard(|| {
+        let Ok(Some(host)) = (unsafe { opt_cstr(host) }) else {
+            return PunktfunkStatus::NullPointer;
+        };
+        if crate::client::NativeClient::probe(
+            host,
+            port,
+            std::time::Duration::from_millis(timeout_ms as u64),
+        ) {
+            PunktfunkStatus::Ok
+        } else {
+            PunktfunkStatus::Timeout
+        }
+    })
+}
+
 /// Run the PIN pairing ceremony against a host (see the protocol docs in punktfunk-core):
 /// the host displays a short PIN; the user types it into the client app, which passes it
 /// here. On success the host has stored this client's identity, the now-verified host

crates/punktfunk-core/src/client.rs

@@ -708,6 +708,56 @@ impl NativeClient {
         })
     }
 
+    /// A lightweight, trust-agnostic reachability check: attempt the QUIC/TLS handshake to
+    /// `host:port` and report whether the host answered — WITHOUT relying on mDNS presence.
+    ///
+    /// The saved-hosts "online" pip historically read a host as offline whenever it wasn't
+    /// currently advertising on mDNS, so a host reached over a routed network (Tailscale / VPN /
+    /// another subnet) — which is mDNS-blind forever — always looked offline even though it was
+    /// perfectly reachable (the same failure the dial-first reconnect fix addressed for the
+    /// connect action). This probe answers the real question ("does the box respond on the
+    /// stream port?") by completing just the handshake and tearing it straight down.
+    ///
+    /// No pin and no identity are presented: hosts accept the transport-level connection
+    /// regardless of pairing (client-cert auth is not mandatory at the QUIC layer —
+    /// authorization is enforced per-feature), so a completed handshake means "reachable". A
+    /// wrong address, closed port, or unroutable host fails the connect/`timeout` and yields
+    /// `false`. Blocks up to `timeout`.
+    pub fn probe(host: &str, port: u16, timeout: Duration) -> bool {
+        let Ok(rt) = tokio::runtime::Builder::new_current_thread()
+            .enable_all()
+            .build()
+        else {
+            return false;
+        };
+        let host = host.to_string();
+        rt.block_on(async move {
+            // The stored address may be a hostname (Tailscale MagicDNS, an mDNS `.local` name),
+            // not a bare IP literal, so resolve it rather than `SocketAddr::parse`.
+            let Ok(mut addrs) = tokio::net::lookup_host((host.as_str(), port)).await else {
+                return false;
+            };
+            let Some(remote) = addrs.next() else {
+                return false;
+            };
+            // TOFU verifier (pin = None) accepts any cert, so a real host always completes the
+            // handshake; the only failures are DNS / no route / connect timeout.
+            let (ep, _observed) = endpoint::client_pinned_with_identity(None, None);
+            let Ok(ep) = ep else {
+                return false;
+            };
+            let reachable = match ep.connect(remote, "punktfunk") {
+                Ok(connecting) => {
+                    matches!(tokio::time::timeout(timeout, connecting).await, Ok(Ok(_)))
+                }
+                Err(_) => false,
+            };
+            ep.close(0u32.into(), b"probe");
+            let _ = tokio::time::timeout(Duration::from_millis(200), ep.wait_idle()).await;
+            reachable
+        })
+    }
+
     /// The currently active session mode — the Welcome's, until an accepted
     /// [`NativeClient::request_mode`] switches it.
     pub fn mode(&self) -> Mode {

crates/punktfunk-core/src/lib.rs

@@ -53,7 +53,9 @@ pub use stats::Stats;
 /// added `punktfunk_pair` / `punktfunk_generate_identity` / `punktfunk_connection_request_mode`.
 /// v3: added `punktfunk_wake_on_lan` (Wake-on-LAN magic packet; the host's wake MAC(s) reach
 /// clients out-of-band via the mDNS `mac` TXT record, so no connection is required to wake).
-pub const ABI_VERSION: u32 = 3;
+/// v4: added `punktfunk_probe` (bounded, trust-agnostic, mDNS-independent reachability handshake —
+/// the display-side companion to dial-first, so saved-host "online" pips reflect real reachability).
+pub const ABI_VERSION: u32 = 4;
 
 /// The punktfunk/1 **wire** version — what `Hello`/`Welcome` carry and hosts equality-check.
 /// Deliberately its own constant: [`ABI_VERSION`] tracks the embeddable **C surface**

include/punktfunk_core.h

@@ -19,7 +19,9 @@
 // added `punktfunk_pair` / `punktfunk_generate_identity` / `punktfunk_connection_request_mode`.
 // v3: added `punktfunk_wake_on_lan` (Wake-on-LAN magic packet; the host's wake MAC(s) reach
 // clients out-of-band via the mDNS `mac` TXT record, so no connection is required to wake).
-#define ABI_VERSION 3
+// v4: added `punktfunk_probe` (bounded, trust-agnostic, mDNS-independent reachability handshake —
+// the display-side companion to dial-first, so saved-host "online" pips reflect real reachability).
+#define ABI_VERSION 4
 
 // The punktfunk/1 **wire** version — what `Hello`/`Welcome` carry and hosts equality-check.
 // Deliberately its own constant: [`ABI_VERSION`] tracks the embeddable **C surface**
@@ -1142,6 +1144,20 @@ PunktfunkStatus punktfunk_generate_identity(char *cert_pem_out,
                                             uintptr_t key_cap);
 #endif
 
+#if defined(PUNKTFUNK_FEATURE_QUIC)
+// Reachability probe: attempt the QUIC handshake to `host:port` and report whether the host
+// answered — trust-agnostic and mDNS-INDEPENDENT. A host reached over a routed network
+// (Tailscale/VPN/another subnet) answers here even though it never advertises on mDNS, so the
+// clients' saved-host "online" pips can reflect real reachability instead of LAN presence (the
+// display-side companion to the dial-first connect fix). Returns [`PunktfunkStatus::Ok`] when
+// reachable, [`PunktfunkStatus::Timeout`] when not (or on any connect error). Blocks up to
+// `timeout_ms`; call off the UI thread.
+//
+// # Safety
+// `host` must be a NUL-terminated UTF-8 string.
+PunktfunkStatus punktfunk_probe(const char *host, uint16_t port, uint32_t timeout_ms);
+#endif
+
 #if defined(PUNKTFUNK_FEATURE_QUIC)
 // Run the PIN pairing ceremony against a host (see the protocol docs in punktfunk-core):
 // the host displays a short PIN; the user types it into the client app, which passes it