diff --git a/sources/ui/aiassistantdialog.cpp b/sources/ui/aiassistantdialog.cpp
index b9f7ac355..6d8542d7e 100644
--- a/sources/ui/aiassistantdialog.cpp
+++ b/sources/ui/aiassistantdialog.cpp
@@ -77,6 +77,28 @@ AiAssistantDialog::AiAssistantDialog(QWidget *parent) :
 		layout->addWidget(missing);
 	}
 
+	if (!m_paths.server.isEmpty()
+	    && m_paths.python_status != AiAssistantSetup::PythonStatus::Found) {
+		QString text;
+		if (m_paths.python_status == AiAssistantSetup::PythonStatus::StoreShortcut)
+			text = tr("<b>Python n'est peut-être pas installé.</b> Seul le raccourci "
+				  "« python » du Microsoft Store a été trouvé : sans Python, il "
+				  "ouvre le Store au lieu de lancer le serveur.");
+		else
+			text = tr("<b>Python est introuvable sur cet ordinateur</b> (commande "
+				  "« %1 »). Le serveur en a besoin.").arg(m_paths.python);
+		if (windows)
+			text += QLatin1Char(' ') + tr("Relancez l'installateur de QElectroTech et "
+						      "cochez « Python pour l'assistant IA », ou "
+						      "installez Python depuis python.org.");
+		else
+			text += QLatin1Char(' ') + tr("Installez Python 3 avec le gestionnaire "
+						      "de paquets de votre système.");
+		auto *python = new QLabel(text, this);
+		python->setWordWrap(true);
+		layout->addWidget(python);
+	}
+
 	auto *form = new QFormLayout();
 	m_client = new QComboBox(this);
 	m_client->addItem(QStringLiteral("Claude Desktop"), int(Client::ClaudeDesktop));
diff --git a/sources/ui/aiassistantsetup.cpp b/sources/ui/aiassistantsetup.cpp
index d484fc6e0..6bb0923dc 100644
--- a/sources/ui/aiassistantsetup.cpp
+++ b/sources/ui/aiassistantsetup.cpp
@@ -22,6 +22,7 @@
 #include <QJsonArray>
 #include <QJsonDocument>
 #include <QJsonObject>
+#include <QStandardPaths>
 
 namespace {
 
@@ -79,10 +80,13 @@ QList<AiAssistantSetup::Client> AiAssistantSetup::clients()
 	@param application_dir : QCoreApplication::applicationDirPath()
 	@param application_file : QCoreApplication::applicationFilePath()
 	@param windows : true on Windows, where Python is "python", not "python3"
+	@param find_executable : looks a program up on PATH; empty means
+	QStandardPaths::findExecutable(). Given in tests.
 */
 AiAssistantSetup::Paths AiAssistantSetup::detect(const QString &application_dir,
 						 const QString &application_file,
-						 bool windows)
+						 bool windows,
+						 const ExecutableFinder &find_executable)
 {
 	const QDir bin(application_dir);
 	Paths paths;
@@ -95,9 +99,28 @@ AiAssistantSetup::Paths AiAssistantSetup::detect(const QString &application_dir,
 	if (windows) {
 		const QString bundled = firstFile({
 			bin.filePath(QStringLiteral("../mcp/python/python.exe"))});
-		if (!bundled.isEmpty())
+		if (!bundled.isEmpty()) {
 			paths.python = bundled;
+			paths.python_status = PythonStatus::Found;
+			return paths;
+		}
 	}
+
+	const ExecutableFinder find = find_executable
+			? find_executable
+			: ExecutableFinder([](const QString &name) {
+				  return QStandardPaths::findExecutable(name); });
+	const QString found = find(paths.python);
+	if (found.isEmpty())
+		paths.python_status = PythonStatus::Missing;
+	// Windows 10 and 11 put a python.exe in WindowsApps that only opens the
+	// Microsoft Store. A Python installed from the Store answers from there
+	// too, so this cannot tell the two apart: say which it may be.
+	else if (windows && QString(found).replace(QLatin1Char('\\'), QLatin1Char('/'))
+			 .contains(QLatin1String("/WindowsApps/"), Qt::CaseInsensitive))
+		paths.python_status = PythonStatus::StoreShortcut;
+	else
+		paths.python_status = PythonStatus::Found;
 	return paths;
 }
 
diff --git a/sources/ui/aiassistantsetup.h b/sources/ui/aiassistantsetup.h
index 144a74020..799e91c63 100644
--- a/sources/ui/aiassistantsetup.h
+++ b/sources/ui/aiassistantsetup.h
@@ -21,6 +21,8 @@
 #include <QString>
 #include <QStringList>
 
+#include <functional>
+
 /**
 	@brief What an AI assistant needs to start QElectroTech's MCP server
 	(misc/qet-mcp), and the configuration text each assistant expects.
@@ -44,16 +46,30 @@ namespace AiAssistantSetup
 
 	QList<Client> clients();
 
+	/// Whether the Python the configuration names can actually run.
+	enum class PythonStatus {
+		Found,
+		Missing,
+		/// Only Windows' "python.exe" shortcut in WindowsApps, which opens
+		/// the Microsoft Store when Python is not installed.
+		StoreShortcut
+	};
+
 	/// Where the pieces are. An empty server means none was found.
 	struct Paths {
 		QString server;     ///< qet_mcp.py
 		QString python;     ///< the Python to run it with
 		QString qet_binary; ///< this QElectroTech
+		PythonStatus python_status = PythonStatus::Missing;
 	};
 
+	/// Finds a program on PATH; QStandardPaths::findExecutable() by default.
+	using ExecutableFinder = std::function<QString(const QString &)>;
+
 	Paths detect(const QString &application_dir,
 		     const QString &application_file,
-		     bool windows);
+		     bool windows,
+		     const ExecutableFinder &find_executable = ExecutableFinder());
 
 	QString configuration(Client client,
 			      const Paths &paths,
diff --git a/tests/qttest/tst_aiassistantsetup.cpp b/tests/qttest/tst_aiassistantsetup.cpp
index 09912077e..b7b566bcf 100644
--- a/tests/qttest/tst_aiassistantsetup.cpp
+++ b/tests/qttest/tst_aiassistantsetup.cpp
@@ -97,6 +97,53 @@ class TestAiAssistantSetup : public QObject
 			QCOMPARE(p.python, QStringLiteral("python3"));
 		}
 
+		void bundledPythonIsFoundWithoutLookingOnPath()
+		{
+			QTemporaryDir root;
+			touch(root.filePath(QStringLiteral("mcp/qet_mcp.py")));
+			touch(root.filePath(QStringLiteral("mcp/python/python.exe")));
+			QDir().mkpath(root.filePath(QStringLiteral("bin")));
+			bool looked = false;
+			const auto p = AiAssistantSetup::detect(root.filePath(QStringLiteral("bin")),
+				root.filePath(QStringLiteral("bin/QElectroTech.exe")), true,
+				[&looked](const QString &) { looked = true; return QString(); });
+			QCOMPARE(p.python_status, AiAssistantSetup::PythonStatus::Found);
+			QVERIFY(!looked);
+		}
+
+		void pythonStatusFromPath_data()
+		{
+			QTest::addColumn<bool>("windows");
+			QTest::addColumn<QString>("found");
+			QTest::addColumn<int>("status");
+			using S = AiAssistantSetup::PythonStatus;
+			QTest::newRow("windows, none") << true << QString() << int(S::Missing);
+			QTest::newRow("windows, python.org") << true
+				<< QStringLiteral("C:/Users/me/AppData/Local/Programs/Python/Python314/python.exe") << int(S::Found);
+			QTest::newRow("windows, Store shortcut") << true
+				<< QStringLiteral("C:/Users/me/AppData/Local/Microsoft/WindowsApps/python.exe") << int(S::StoreShortcut);
+			QTest::newRow("windows, Store shortcut, backslashes") << true
+				<< QStringLiteral("C:\\Users\\me\\AppData\\Local\\Microsoft\\WINDOWSAPPS\\python.exe") << int(S::StoreShortcut);
+			QTest::newRow("linux, none") << false << QString() << int(S::Missing);
+			QTest::newRow("linux, python3") << false << QStringLiteral("/usr/bin/python3") << int(S::Found);
+			QTest::newRow("linux, a folder named WindowsApps") << false
+				<< QStringLiteral("/opt/WindowsApps/python3") << int(S::Found);
+		}
+
+		void pythonStatusFromPath()
+		{
+			QFETCH(bool, windows);
+			QFETCH(QString, found);
+			QFETCH(int, status);
+			QTemporaryDir build;
+			QString asked;
+			const auto p = AiAssistantSetup::detect(build.path(),
+				build.filePath(QStringLiteral("qelectrotech")), windows,
+				[&](const QString &name) { asked = name; return found; });
+			QCOMPARE(int(p.python_status), status);
+			QCOMPARE(asked, windows ? QStringLiteral("python") : QStringLiteral("python3"));
+		}
+
 		void noServerIsReportedAsEmpty()
 		{
 			QTemporaryDir build;