diff --git a/app/api/mcp/route.ts b/app/api/mcp/route.ts
index 1ebf627b..90bd1058 100644
--- a/app/api/mcp/route.ts
+++ b/app/api/mcp/route.ts
@@ -2306,9 +2306,16 @@ async function toolAppsDomainsSet(principal: Principal, params: Record<string, a
     const fqdnsForUrl = normalized
       .map((d) => `https://${d}${port ? `:${port}` : ''}`)
       .join(',');
-    // PHP code: load service, find target inner app by name (or auto-pick),
-    // set fqdn, save, regenerate compose, re-parse. All quoting carefully
-    // escaped because we shell this through ssh.
+    // PHP code: load service, find target inner app, save fqdn, then
+    // INLINE-REPLACE ${SERVICE_URL_<NAME>} / ${SERVICE_FQDN_<NAME>}
+    // interpolations in docker_compose_raw with the literal user-provided
+    // URL. This bypasses Coolify's parse() — which iterates ALL apps in
+    // a multi-container template (twenty + worker + redis + postgres)
+    // and overwrites SERVICE_URL_<NAME> env vars based on whichever
+    // ServiceApplication.fqdn it sees first, often producing the
+    // *.sslip.io fallback. Hardcoding the URL into the compose template
+    // makes the deploy survive future parse() calls (which the deploy
+    // job runs internally on every redeploy).
     const phpCode = `
 $service = App\\Models\\Service::where('uuid', '${appUuid}')->first();
 if (!$service) { echo 'service-not-found'; exit; }
@@ -2317,8 +2324,42 @@ $target = ${inner === 'auto' ? '$apps->first(fn($a) => !str_contains(strtolower(
 if (!$target) { echo 'inner-app-not-found'; exit; }
 $target->fqdn = '${fqdnsForUrl}';
 $target->save();
+
+// Parse the saved fqdn into base URL + bare host so we can substitute.
+$first = explode(',', $target->fqdn)[0];
+preg_match('#^(https?://)([^:/]+)(?::(\\\\d+))?#', $first, $mm);
+$scheme = $mm[1] ?? 'https://';
+$host = $mm[2] ?? '';
+$urlBase = $scheme . $host;
+$fqdnBase = $host;
+
+// Compose template uses the inner app NAME uppercased, dashes→underscores.
+$svcVar = strtoupper(str_replace('-', '_', $target->name));
+$raw = $service->docker_compose_raw ?? '';
+
+// Replace port-specific first so the bare match below doesn't eat the prefix.
+$raw = preg_replace_callback(
+    '/\\\\$\\\\{SERVICE_URL_' . preg_quote($svcVar, '/') . '_(\\\\d+)\\\\}/',
+    fn($m) => $urlBase . ':' . $m[1],
+    $raw
+);
+$raw = preg_replace_callback(
+    '/\\\\$\\\\{SERVICE_FQDN_' . preg_quote($svcVar, '/') . '_(\\\\d+)\\\\}/',
+    fn($m) => $fqdnBase . ':' . $m[1],
+    $raw
+);
+$raw = str_replace('\\\${SERVICE_URL_' . $svcVar . '}', $urlBase, $raw);
+$raw = str_replace('\\\${SERVICE_FQDN_' . $svcVar . '}', $fqdnBase, $raw);
+
+$service->docker_compose_raw = $raw;
+$service->save();
+
+// updateCompose() rewrites the rendered docker_compose output and the
+// SERVICE_URL_/SERVICE_FQDN_ env vars from $target->fqdn. We deliberately
+// SKIP $service->parse() because it picks the wrong inner app in
+// multi-container templates and reverts env vars to sslip.io.
 updateCompose($target);
-$service->parse();
+
 echo 'fqdn-saved=' . $target->fresh()->fqdn;
 `;
     const result = await runOnCoolifyHost(