diff --git a/src/cascadia/TerminalApp/TerminalPage.Protocol.cpp b/src/cascadia/TerminalApp/TerminalPage.Protocol.cpp
index f91c43543..da3926dbf 100644
--- a/src/cascadia/TerminalApp/TerminalPage.Protocol.cpp
+++ b/src/cascadia/TerminalApp/TerminalPage.Protocol.cpp
@@ -153,6 +153,8 @@ namespace winrt::TerminalApp::implementation
         if (const auto termControl = effectivePane->GetTerminalControl())
         {
             result.Cwd = termControl.WorkingDirectory();
+            result.Shell = termControl.ShellName();
+            result.ShellVersion = termControl.ShellVersion();
         }
 
         result.Pid = _getPidFromPane(effectivePane);
@@ -256,6 +258,8 @@ namespace winrt::TerminalApp::implementation
                         info.Rows = termControl.ViewHeight();
                         info.Columns = 0;
                         info.Cwd = termControl.WorkingDirectory();
+                        info.Shell = termControl.ShellName();
+                        info.ShellVersion = termControl.ShellVersion();
                     }
                 }
 
diff --git a/src/cascadia/TerminalControl/ControlCore.cpp b/src/cascadia/TerminalControl/ControlCore.cpp
index db973d631..057c6b73c 100644
--- a/src/cascadia/TerminalControl/ControlCore.cpp
+++ b/src/cascadia/TerminalControl/ControlCore.cpp
@@ -1522,6 +1522,18 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return hstring{ _terminal->GetWorkingDirectory() };
     }
 
+    hstring ControlCore::ShellName() const
+    {
+        const auto lock = _terminal->LockForReading();
+        return hstring{ _terminal->GetShellName() };
+    }
+
+    hstring ControlCore::ShellVersion() const
+    {
+        const auto lock = _terminal->LockForReading();
+        return hstring{ _terminal->GetShellVersion() };
+    }
+
     bool ControlCore::BracketedPasteEnabled() const noexcept
     {
         const auto lock = _terminal->LockForReading();
diff --git a/src/cascadia/TerminalControl/ControlCore.h b/src/cascadia/TerminalControl/ControlCore.h
index bbc03a50e..811728d05 100644
--- a/src/cascadia/TerminalControl/ControlCore.h
+++ b/src/cascadia/TerminalControl/ControlCore.h
@@ -167,6 +167,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         hstring Title();
         Windows::Foundation::IReference<winrt::Windows::UI::Color> TabColor() noexcept;
         hstring WorkingDirectory() const;
+        hstring ShellName() const;
+        hstring ShellVersion() const;
 
         TerminalConnection::ConnectionState ConnectionState() const;
 
diff --git a/src/cascadia/TerminalControl/ICoreState.idl b/src/cascadia/TerminalControl/ICoreState.idl
index f03d0391c..c20bfc667 100644
--- a/src/cascadia/TerminalControl/ICoreState.idl
+++ b/src/cascadia/TerminalControl/ICoreState.idl
@@ -36,6 +36,12 @@ namespace Microsoft.Terminal.Control
 
         String WorkingDirectory { get; };
 
+        // Shell identity reported by shell integration via OSC 9001;ShellType.
+        // Empty when the shell has not reported (no shell integration, or a
+        // shell that does not emit the sequence).
+        String ShellName { get; };
+        String ShellVersion { get; };
+
         Windows.Foundation.IReference<Windows.UI.Color> TabColor { get; };
 
         Int32 ScrollOffset { get; };
diff --git a/src/cascadia/TerminalControl/TermControl.cpp b/src/cascadia/TerminalControl/TermControl.cpp
index 95d0e11b7..0840d23ba 100644
--- a/src/cascadia/TerminalControl/TermControl.cpp
+++ b/src/cascadia/TerminalControl/TermControl.cpp
@@ -2550,6 +2550,16 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         return _core.WorkingDirectory();
     }
 
+    hstring TermControl::ShellName() const
+    {
+        return _core.ShellName();
+    }
+
+    hstring TermControl::ShellVersion() const
+    {
+        return _core.ShellVersion();
+    }
+
     bool TermControl::BracketedPasteEnabled() const noexcept
     {
         return _core.BracketedPasteEnabled();
diff --git a/src/cascadia/TerminalControl/TermControl.h b/src/cascadia/TerminalControl/TermControl.h
index f88a2aa83..f08fc6c90 100644
--- a/src/cascadia/TerminalControl/TermControl.h
+++ b/src/cascadia/TerminalControl/TermControl.h
@@ -92,6 +92,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         hstring Title();
         Windows::Foundation::IReference<winrt::Windows::UI::Color> TabColor() noexcept;
         hstring WorkingDirectory() const;
+        hstring ShellName() const;
+        hstring ShellVersion() const;
 
         TerminalConnection::ConnectionState ConnectionState() const;
 
diff --git a/src/cascadia/TerminalCore/Terminal.cpp b/src/cascadia/TerminalCore/Terminal.cpp
index b63cf1217..a76e79218 100644
--- a/src/cascadia/TerminalCore/Terminal.cpp
+++ b/src/cascadia/TerminalCore/Terminal.cpp
@@ -280,6 +280,16 @@ std::wstring_view Terminal::GetWorkingDirectory() noexcept
     return _workingDirectory;
 }
 
+std::wstring_view Terminal::GetShellName() const noexcept
+{
+    return _shellName;
+}
+
+std::wstring_view Terminal::GetShellVersion() const noexcept
+{
+    return _shellVersion;
+}
+
 // Method Description:
 // - Resize the terminal as the result of some user interaction.
 // Arguments:
diff --git a/src/cascadia/TerminalCore/Terminal.hpp b/src/cascadia/TerminalCore/Terminal.hpp
index b05f3987c..d0a974d80 100644
--- a/src/cascadia/TerminalCore/Terminal.hpp
+++ b/src/cascadia/TerminalCore/Terminal.hpp
@@ -99,6 +99,8 @@ class Microsoft::Terminal::Core::Terminal final :
     void SetOptionalFeatures(winrt::Microsoft::Terminal::Core::ICoreSettings settings);
     bool IsXtermBracketedPasteModeEnabled() const noexcept;
     std::wstring_view GetWorkingDirectory() noexcept;
+    std::wstring_view GetShellName() const noexcept;
+    std::wstring_view GetShellVersion() const noexcept;
 
     til::point GetViewportRelativeCursorPosition() const noexcept;
 
@@ -152,6 +154,7 @@ class Microsoft::Terminal::Core::Terminal final :
     void CopyToClipboard(wil::zwstring_view content) override;
     void SetTaskbarProgress(const ::Microsoft::Console::VirtualTerminal::DispatchTypes::TaskbarState state, const size_t progress) override;
     void SetWorkingDirectory(std::wstring_view uri) override;
+    void SetShellType(std::wstring_view shellName, std::wstring_view shellVersion) override;
     void PlayMidiNote(const int noteNumber, const int velocity, const std::chrono::microseconds duration) override;
     void ShowWindow(bool showOrHide) override;
     void UseAlternateScreenBuffer(const TextAttribute& attrs) override;
@@ -382,6 +385,8 @@ class Microsoft::Terminal::Core::Terminal final :
 
     std::wstring _answerbackMessage;
     std::wstring _workingDirectory;
+    std::wstring _shellName;
+    std::wstring _shellVersion;
     bool _highContrastMode = false;
 
     // This default fake font value is only used to check if the font is a raster font.
diff --git a/src/cascadia/TerminalCore/TerminalApi.cpp b/src/cascadia/TerminalCore/TerminalApi.cpp
index 14c384881..8562ff90c 100644
--- a/src/cascadia/TerminalCore/TerminalApi.cpp
+++ b/src/cascadia/TerminalCore/TerminalApi.cpp
@@ -7,6 +7,8 @@
 
 #include "../src/inc/unicode.hpp"
 
+#include <atomic>
+
 using namespace Microsoft::Terminal::Core;
 using namespace Microsoft::Console::Render;
 using namespace Microsoft::Console::Types;
@@ -234,6 +236,29 @@ void Terminal::SetWorkingDirectory(std::wstring_view uri)
     _workingDirectory = uri;
 }
 
+void Terminal::SetShellType(std::wstring_view shellName, std::wstring_view shellVersion)
+{
+    _assertLocked();
+
+    // Telemetry is logged once per process. `logged` is function-static
+    // (shared across all Terminal instances, which hold *different* locks),
+    // so the `_assertLocked()` above does NOT serialize it — use an atomic
+    // exchange to make the one-shot gate race-free.
+    static std::atomic<bool> logged{ false };
+    if (!logged.exchange(true))
+    {
+        TraceLoggingWrite(
+            g_hCTerminalCoreProvider,
+            "ShellIntegrationShellTypeSet",
+            TraceLoggingDescription("The shell reported its identity via OSC 9001;ShellType"),
+            TraceLoggingKeyword(MICROSOFT_KEYWORD_MEASURES),
+            TelemetryPrivacyDataTag(PDT_ProductAndServiceUsage));
+    }
+
+    _shellName = shellName;
+    _shellVersion = shellVersion;
+}
+
 void Terminal::PlayMidiNote(const int noteNumber, const int velocity, const std::chrono::microseconds duration)
 {
     _pfnPlayMidiNote(noteNumber, velocity, duration);
diff --git a/src/cascadia/TerminalProtocol/TerminalProtocol.idl b/src/cascadia/TerminalProtocol/TerminalProtocol.idl
index 95f9a09ef..089f71b1f 100644
--- a/src/cascadia/TerminalProtocol/TerminalProtocol.idl
+++ b/src/cascadia/TerminalProtocol/TerminalProtocol.idl
@@ -38,6 +38,11 @@ namespace Microsoft.Terminal.Protocol
         // terminal control's working-directory tracking (OSC 9;9 / shell
         // integration). Empty when not known.
         String Cwd;
+        // Shell identity reported by shell integration via OSC 9001;ShellType
+        // (e.g. "pwsh", "powershell", "bash", "wsl:Ubuntu"). Empty when the
+        // shell has not reported its identity.
+        String Shell;
+        String ShellVersion;
     };
 
     struct PaneOutput
diff --git a/src/cascadia/UnitTests_TerminalCore/ShellIntegrationTests.cpp b/src/cascadia/UnitTests_TerminalCore/ShellIntegrationTests.cpp
index e598e9c2a..3ed56ea0a 100644
--- a/src/cascadia/UnitTests_TerminalCore/ShellIntegrationTests.cpp
+++ b/src/cascadia/UnitTests_TerminalCore/ShellIntegrationTests.cpp
@@ -60,6 +60,7 @@ class TerminalCoreUnitTests::ShellIntegrationTests final
     TEST_METHOD(Install_IdempotentWhenAlreadyInstalled);
     TEST_METHOD(Install_ReinstallsWhenScriptMissingButBlockMatches);
     TEST_METHOD(Install_RewritesLegacyDotSourceLineInPlace);
+    TEST_METHOD(Install_UpgradesWhenBlockReferencesOlderScriptVersion);
     TEST_METHOD(Install_OverwritesOrphanOpenMarker);
     TEST_METHOD(Install_CreatesBackupForNonEmptyProfile);
     TEST_METHOD(Install_DoesNotCreateBackupForEmptyProfile);
@@ -119,6 +120,7 @@ class TerminalCoreUnitTests::ShellIntegrationTests final
     TEST_METHOD(Bash_Install_IsLfOnly);
     TEST_METHOD(Bash_Install_IdempotentWhenAlreadyInstalled);
     TEST_METHOD(Bash_Install_ReinstallsWhenScriptMissingButBlockMatches);
+    TEST_METHOD(Bash_Install_UpgradesWhenBlockReferencesOlderScriptVersion);
     TEST_METHOD(Bash_Install_OverwritesOrphanOpenMarker);
     TEST_METHOD(Bash_Install_CreatesBackupForNonEmptyProfile);
     TEST_METHOD(Bash_Install_DoesNotCreateBackupForEmptyProfile);
@@ -546,6 +548,43 @@ void ShellIntegrationTests::Install_RewritesLegacyDotSourceLineInPlace()
     VERIFY_IS_TRUE(blockPos < tailPos, L"In-place rewrite — block stays where legacy line was");
 }
 
+void ShellIntegrationTests::Install_UpgradesWhenBlockReferencesOlderScriptVersion()
+{
+    // Regression: bumping the script version (e.g. v1 -> v2 when OSC
+    // 9001;ShellType emission was added) must actually reach existing
+    // users. Their $PROFILE already has a well-formed managed block, but it
+    // references the OLDER versioned script filename and the stale old
+    // script sits on disk. The block-match early-out must NOT fire (the
+    // block no longer equals the desired, current-version block), so the
+    // current script is written and the block is rewritten to point at it.
+    const auto profile = _ProfilePath();
+    const auto currentName = til::u16u8(ShellIntegrationScriptFileName());
+
+    // Simulate a prior install: take the current block and point it at an
+    // older script version. v0 is always older than any shipped vN, so this
+    // stays valid across future bumps.
+    const std::string oldName = "shell-integration_v0.ps1";
+    auto oldBlock = BuildShellIntegrationBlock(L"PowerShell", "\n");
+    const auto namePos = oldBlock.find(currentName);
+    VERIFY_ARE_NOT_EQUAL(std::string::npos, namePos, L"Block must embed the current script filename");
+    oldBlock.replace(namePos, currentName.size(), oldName);
+    _WriteFile(profile, oldBlock + "\n");
+    // Stale old script on disk, without the ShellType emission.
+    _WriteFile(profile.parent_path() / L"shell-integration_v0.ps1", "# stale old script, no ShellType\n");
+
+    const auto r = Install(profile.wstring());
+    VERIFY_IS_TRUE(r.success);
+    VERIFY_IS_FALSE(r.alreadyInstalled, L"Block referenced an older script version → must upgrade, not no-op");
+
+    const auto contents = _ReadFile(profile);
+    VERIFY_IS_TRUE(_Contains(contents, currentName), L"Block must be rewritten to the current script version");
+    VERIFY_IS_FALSE(_Contains(contents, oldName), L"Old version reference must be replaced");
+
+    const auto scriptPath = profile.parent_path() / ShellIntegrationScriptFileName();
+    VERIFY_IS_TRUE(std::filesystem::exists(scriptPath), L"Current-version script must be written on upgrade");
+    VERIFY_IS_TRUE(_Contains(_ReadFile(scriptPath), "9001"), L"Upgraded script must emit OSC 9001;ShellType");
+}
+
 void ShellIntegrationTests::Install_OverwritesOrphanOpenMarker()
 {
     const auto profile = _ProfilePath();
@@ -1210,6 +1249,38 @@ void ShellIntegrationTests::Bash_Install_ReinstallsWhenScriptMissingButBlockMatc
     VERIFY_IS_TRUE(std::filesystem::exists(scriptPath));
 }
 
+void ShellIntegrationTests::Bash_Install_UpgradesWhenBlockReferencesOlderScriptVersion()
+{
+    // Bash/WSL counterpart of the PowerShell upgrade regression: an existing
+    // ~/.bashrc managed block that references an OLDER versioned script must
+    // be rewritten to the current version (so the OSC 9001;ShellType emission
+    // added in v2 actually reaches users who already had v1 installed).
+    const auto profile = _BashProfilePath();
+    const auto scriptDir = _BashScriptDir();
+    const auto currentName = til::u16u8(ShellIntegrationBashScriptFileName());
+
+    const std::string oldName = "shell-integration_v0.sh";
+    auto oldBlock = BuildShellIntegrationBashBlock();
+    const auto namePos = oldBlock.find(currentName);
+    VERIFY_ARE_NOT_EQUAL(std::string::npos, namePos, L"Block must embed the current script filename");
+    oldBlock.replace(namePos, currentName.size(), oldName);
+    _WriteFile(profile, oldBlock + "\n");
+    // Stale old script on disk, without the ShellType emission.
+    _WriteFile(scriptDir / L"shell-integration_v0.sh", "# stale old script, no ShellType\n");
+
+    const auto r = InstallBash(profile.wstring(), scriptDir.wstring());
+    VERIFY_IS_TRUE(r.success);
+    VERIFY_IS_FALSE(r.alreadyInstalled, L"Block referenced an older script version → must upgrade, not no-op");
+
+    const auto contents = _ReadFile(profile);
+    VERIFY_IS_TRUE(_Contains(contents, currentName), L"Block must be rewritten to the current script version");
+    VERIFY_IS_FALSE(_Contains(contents, oldName), L"Old version reference must be replaced");
+
+    const auto scriptPath = scriptDir / ShellIntegrationBashScriptFileName();
+    VERIFY_IS_TRUE(std::filesystem::exists(scriptPath), L"Current-version script must be written on upgrade");
+    VERIFY_IS_TRUE(_Contains(_ReadFile(scriptPath), "9001"), L"Upgraded script must emit OSC 9001;ShellType");
+}
+
 void ShellIntegrationTests::Bash_Install_OverwritesOrphanOpenMarker()
 {
     const auto profile = _BashProfilePath();
diff --git a/src/cascadia/UnitTests_TerminalCore/TerminalApiTest.cpp b/src/cascadia/UnitTests_TerminalCore/TerminalApiTest.cpp
index 51e53f173..0e5f67eac 100644
--- a/src/cascadia/UnitTests_TerminalCore/TerminalApiTest.cpp
+++ b/src/cascadia/UnitTests_TerminalCore/TerminalApiTest.cpp
@@ -39,6 +39,7 @@ namespace TerminalCoreUnitTests
 
         TEST_METHOD(SetTaskbarProgress);
         TEST_METHOD(SetWorkingDirectory);
+        TEST_METHOD(SetShellType);
     };
 };
 
@@ -391,3 +392,44 @@ void TerminalCoreUnitTests::TerminalApiTest::SetWorkingDirectory()
     stateMachine.ProcessString(L"\x1b]9;9;D:\\中文\x1b\\");
     VERIFY_ARE_EQUAL(term.GetWorkingDirectory(), L"D:\\中文");
 }
+
+void TerminalCoreUnitTests::TerminalApiTest::SetShellType()
+{
+    Terminal term{ Terminal::TestDummyMarker{} };
+    DummyRenderer renderer{ &term };
+    term.Create({ 100, 100 }, 0, renderer);
+
+    auto& stateMachine = *(term._stateMachine);
+
+    // The shell reports its identity via OSC 9001;ShellType;<name>;<version>.
+    // Initially nothing has been reported.
+    VERIFY_IS_TRUE(term.GetShellName().empty());
+    VERIFY_IS_TRUE(term.GetShellVersion().empty());
+
+    // Name + version both present.
+    stateMachine.ProcessString(L"\x1b]9001;ShellType;pwsh;7.4.1\x1b\\");
+    VERIFY_ARE_EQUAL(term.GetShellName(), L"pwsh");
+    VERIFY_ARE_EQUAL(term.GetShellVersion(), L"7.4.1");
+
+    // A later prompt from a different shell (e.g. after `wsl` exits) overwrites
+    // the previously reported identity — last writer wins.
+    stateMachine.ProcessString(L"\x1b]9001;ShellType;wsl:Ubuntu;5.15.0\x1b\\");
+    VERIFY_ARE_EQUAL(term.GetShellName(), L"wsl:Ubuntu");
+    VERIFY_ARE_EQUAL(term.GetShellVersion(), L"5.15.0");
+
+    // Version is optional — name only still updates the name and clears version.
+    stateMachine.ProcessString(L"\x1b]9001;ShellType;bash\x1b\\");
+    VERIFY_ARE_EQUAL(term.GetShellName(), L"bash");
+    VERIFY_IS_TRUE(term.GetShellVersion().empty());
+
+    // A ShellType action with no name field is tolerated and clears both.
+    stateMachine.ProcessString(L"\x1b]9001;ShellType\x1b\\");
+    VERIFY_IS_TRUE(term.GetShellName().empty());
+    VERIFY_IS_TRUE(term.GetShellVersion().empty());
+
+    // An unrelated WT sub-action must not touch the stored shell identity.
+    stateMachine.ProcessString(L"\x1b]9001;ShellType;powershell;5.1\x1b\\");
+    stateMachine.ProcessString(L"\x1b]9001;CmdNotFound;somecmd\x1b\\");
+    VERIFY_ARE_EQUAL(term.GetShellName(), L"powershell");
+    VERIFY_ARE_EQUAL(term.GetShellVersion(), L"5.1");
+}
diff --git a/src/cascadia/WindowsTerminal/TerminalProtocolComServer.cpp b/src/cascadia/WindowsTerminal/TerminalProtocolComServer.cpp
index 801898b7c..8639da4bc 100644
--- a/src/cascadia/WindowsTerminal/TerminalProtocolComServer.cpp
+++ b/src/cascadia/WindowsTerminal/TerminalProtocolComServer.cpp
@@ -248,6 +248,8 @@ static Json::Value _toJson(const Protocol::PaneInfo& p)
     v["size"]["rows"] = p.Rows;
     v["size"]["columns"] = p.Columns;
     v["cwd"] = winrt::to_string(p.Cwd);
+    v["shell"] = winrt::to_string(p.Shell);
+    v["shell_version"] = winrt::to_string(p.ShellVersion);
     return v;
 }
 
diff --git a/src/cascadia/inc/BashShellIntegration.h b/src/cascadia/inc/BashShellIntegration.h
index 78ee97cfc..b76df7139 100644
--- a/src/cascadia/inc/BashShellIntegration.h
+++ b/src/cascadia/inc/BashShellIntegration.h
@@ -34,7 +34,13 @@
 
 namespace Microsoft::Terminal::ShellIntegration::Bash
 {
-    inline constexpr int kVersion = 1;
+    // v2: added OSC 9001;ShellType emission (bash/WSL self-reports identity
+    // each prompt). Bumped from v1 so existing users — whose ~/.bashrc
+    // already references the v1 script byte-for-byte — get the new script
+    // rewritten in; without the bump the orchestrator's block-match early-
+    // out would leave the stale v1 script (no ShellType) in place. WSL
+    // inherits this version via WslBashFlavor.
+    inline constexpr int kVersion = 2;
 
     inline std::wstring ScriptFileName()
     {
@@ -143,6 +149,15 @@ __it_shellinteg_prompt() {
     # CWD reporting for those directories. The unquoted form parses
     # cleanly regardless of path contents.
     printf '\033]133;D;%s\007\033]133;A\007\033]9;9;%s\007' "$__ec" "${PWD:-}"
+    # OSC 9001;ShellType — report shell identity each prompt so the terminal
+    # always knows which shell owns the pane, even after a nested shell exits.
+    # Under WSL, $WSL_DISTRO_NAME is set so we report "wsl:<distro>"; plain
+    # (Git) bash reports "bash".
+    if [ -n "${WSL_DISTRO_NAME:-}" ]; then
+        printf '\033]9001;ShellType;wsl:%s;%s\007' "$WSL_DISTRO_NAME" "${BASH_VERSION:-}"
+    else
+        printf '\033]9001;ShellType;bash;%s\007' "${BASH_VERSION:-}"
+    fi
     if [ -n "$__IT_SHELLINTEG_USER_PC" ]; then
         # Restore $? for the user's PROMPT_COMMAND so hooks like
         # `local ec=$?` at its top still see the real exit code
diff --git a/src/cascadia/inc/PowerShellShellIntegration.h b/src/cascadia/inc/PowerShellShellIntegration.h
index fae727f00..13fb56874 100644
--- a/src/cascadia/inc/PowerShellShellIntegration.h
+++ b/src/cascadia/inc/PowerShellShellIntegration.h
@@ -346,8 +346,14 @@ namespace Microsoft::Terminal::ShellIntegration::Powershell
     // `shell-integration*.ps1` reference in $PROFILE and rewrite it to
     // point at the current version. Older script files left on disk are
     // inert (never referenced). To roll out a new version, bump this.
+    //
+    // v2: added OSC 9001;ShellType emission (shell self-reports identity
+    // each prompt). Bumped from v1 so existing users — whose $PROFILE
+    // already references the v1 script byte-for-byte — get the new script
+    // rewritten in; without the bump the orchestrator's block-match early-
+    // out would leave the stale v1 script (no ShellType) in place.
     // ───────────────────────────────────────────────────────────────────
-    inline constexpr int kVersion = 1;
+    inline constexpr int kVersion = 2;
 
     inline std::wstring ScriptFileName()
     {
@@ -437,6 +443,14 @@ if (-not $Global:__ShellInteg_Installed) {
         # ── Report current working directory (OSC 9;9) ──
         $prefix += "${E}]9;9;`"${loc}`"${B}"
 
+        # ── Report shell identity (OSC 9001;ShellType) ──
+        # Emitted every prompt so the terminal always knows which shell owns
+        # the pane, even after a nested shell (e.g. wsl) exits and PowerShell
+        # repaints its prompt. PSEdition 'Core' is pwsh 7+, 'Desktop' is
+        # Windows PowerShell 5.1.
+        $shellName = if ($PSVersionTable.PSEdition -eq 'Core') { 'pwsh' } else { 'powershell' }
+        $prefix += "${E}]9001;ShellType;${shellName};$($PSVersionTable.PSVersion)${B}"
+
         # ── Prompt ended, command input starts (OSC 133;B) ──
         $suffix = "${E}]133;B${B}"
 
diff --git a/src/host/outputStream.cpp b/src/host/outputStream.cpp
index c26e20a74..f389a3195 100644
--- a/src/host/outputStream.cpp
+++ b/src/host/outputStream.cpp
@@ -335,6 +335,18 @@ void ConhostInternalGetSet::SetWorkingDirectory(const std::wstring_view /*uri*/)
 {
 }
 
+// Routine Description:
+// - Records the shell identity reported via OSC 9001;ShellType. This is a
+//   Windows Terminal feature with no meaning in conhost, so it is a no-op here.
+// Arguments:
+// - shellName - the reported shell name (unused in conhost).
+// - shellVersion - the reported shell version (unused in conhost).
+// Return Value:
+// - <none>
+void ConhostInternalGetSet::SetShellType(const std::wstring_view /*shellName*/, const std::wstring_view /*shellVersion*/)
+{
+}
+
 // Routine Description:
 // - Plays a single MIDI note, blocking for the duration.
 // Arguments:
diff --git a/src/host/outputStream.hpp b/src/host/outputStream.hpp
index d61482538..e4bfd502a 100644
--- a/src/host/outputStream.hpp
+++ b/src/host/outputStream.hpp
@@ -63,6 +63,7 @@ class ConhostInternalGetSet final : public Microsoft::Console::VirtualTerminal::
     void CopyToClipboard(const wil::zwstring_view content) override;
     void SetTaskbarProgress(const ::Microsoft::Console::VirtualTerminal::DispatchTypes::TaskbarState state, const size_t progress) override;
     void SetWorkingDirectory(const std::wstring_view uri) override;
+    void SetShellType(const std::wstring_view shellName, const std::wstring_view shellVersion) override;
     void PlayMidiNote(const int noteNumber, const int velocity, const std::chrono::microseconds duration) override;
 
     bool IsVtInputEnabled() const override;
diff --git a/src/terminal/adapter/ITerminalApi.hpp b/src/terminal/adapter/ITerminalApi.hpp
index a6c12ea5e..ab07d788f 100644
--- a/src/terminal/adapter/ITerminalApi.hpp
+++ b/src/terminal/adapter/ITerminalApi.hpp
@@ -82,6 +82,7 @@ namespace Microsoft::Console::VirtualTerminal
         virtual void CopyToClipboard(const wil::zwstring_view content) = 0;
         virtual void SetTaskbarProgress(const DispatchTypes::TaskbarState state, const size_t progress) = 0;
         virtual void SetWorkingDirectory(const std::wstring_view uri) = 0;
+        virtual void SetShellType(const std::wstring_view shellName, const std::wstring_view shellVersion) = 0;
         virtual void PlayMidiNote(const int noteNumber, const int velocity, const std::chrono::microseconds duration) = 0;
 
         virtual bool ResizeWindow(const til::CoordType width, const til::CoordType height) = 0;
diff --git a/src/terminal/adapter/adaptDispatch.cpp b/src/terminal/adapter/adaptDispatch.cpp
index d0b9579d7..c187db0f1 100644
--- a/src/terminal/adapter/adaptDispatch.cpp
+++ b/src/terminal/adapter/adaptDispatch.cpp
@@ -3844,6 +3844,8 @@ void AdaptDispatch::DoVsCodeAction(const std::wstring_view string)
 //     to the terminal. The command is then shared with WinGet to see if it can
 //     find a package that provides that command, which is then displayed to the
 //     user.
+//   * ShellType: The shell reports its own identity (name + version) so the
+//     terminal knows which shell currently owns the pane.
 // - Not actually used in conhost
 // Arguments:
 // - string: contains the parameters that define which action we do
@@ -3870,32 +3872,19 @@ void AdaptDispatch::DoWTAction(const std::wstring_view string)
             _api.SearchMissingCommand(missingCmd);
         }
     }
-    else if (action == L"WtaReq")
+    else if (action == L"ShellType")
     {
-        // WTA (Windows Terminal Agent) protocol request via VT escape sequence.
-        // Format: \x1b]9001;WtaReq;{json}\x07
-        // Supports: {"method":"discover"} → returns pipe name + token for protocol access.
-        // The response is injected back as \x1b]9001;WtaRes;{json}\x1b\\ via stdin.
-        if (parts.size() >= 2)
-        {
-            const auto payload = til::at(parts, 1);
-
-            // Check if this is a "discover" request
-            if (payload.find(L"discover") != std::wstring_view::npos)
-            {
-                // Compute pipe name from current PID — matches what WindowEmperor creates.
-                const auto pid = GetCurrentProcessId();
-                const auto pipeName = fmt::format(FMT_COMPILE(L"\\\\\\\\.\\\\pipe\\\\WindowsTerminal-{}"), pid);
-                const auto response = fmt::format(FMT_COMPILE(L"9001;WtaRes;{{\"status\":\"ok\",\"pipe\":\"{}\",\"token\":\"\"}}"), pipeName);
-                _ReturnOscResponse(response);
-            }
-            else
-            {
-                // Default ack for other methods (e.g. "identify")
-                const auto response = fmt::format(FMT_COMPILE(L"9001;WtaRes;{{\"status\":\"ok\",\"vt_supported\":true}}"));
-                _ReturnOscResponse(response);
-            }
-        }
+        // The shell reports its own identity once per prompt so the terminal
+        // always knows which shell currently owns the pane (including after a
+        // nested shell like `wsl` exits).
+        // The structure of the message is as follows:
+        // `e]9001;
+        // 0:     ShellType;
+        // 1:     <shell name>   (e.g. pwsh, powershell, bash, wsl:Ubuntu)
+        // 2:     <shell version> (optional)
+        const std::wstring_view shellName = parts.size() >= 2 ? til::at(parts, 1) : std::wstring_view{};
+        const std::wstring_view shellVersion = parts.size() >= 3 ? til::at(parts, 2) : std::wstring_view{};
+        _api.SetShellType(shellName, shellVersion);
     }
 }
 
diff --git a/src/terminal/adapter/ut_adapter/adapterTest.cpp b/src/terminal/adapter/ut_adapter/adapterTest.cpp
index 3af5db159..697399105 100644
--- a/src/terminal/adapter/ut_adapter/adapterTest.cpp
+++ b/src/terminal/adapter/ut_adapter/adapterTest.cpp
@@ -206,6 +206,11 @@ class TestGetSet final : public ITerminalApi
         Log::Comment(L"SetWorkingDirectory MOCK called...");
     }
 
+    void SetShellType(const std::wstring_view /*shellName*/, const std::wstring_view /*shellVersion*/) override
+    {
+        Log::Comment(L"SetShellType MOCK called...");
+    }
+
     void PlayMidiNote(const int /*noteNumber*/, const int /*velocity*/, const std::chrono::microseconds /*duration*/) override
     {
         Log::Comment(L"PlayMidiNote MOCK called...");
diff --git a/test/e2e/ItE2E/ItE2E.psm1 b/test/e2e/ItE2E/ItE2E.psm1
index 071c3fcd0..c2048d9f1 100644
--- a/test/e2e/ItE2E/ItE2E.psm1
+++ b/test/e2e/ItE2E/ItE2E.psm1
@@ -14,7 +14,7 @@ foreach ($scope in @('Private', 'Public')) {
 # Export every function defined by the Public files (and the few private ones tests use).
 $publicFns = @(
     # Harness
-    'Resolve-ItApp', 'Resolve-WtComClsid', 'Start-Terminal', 'Start-TerminalClean', 'Stop-Terminal',
+    'Resolve-ItApp', 'Resolve-WtComClsid', 'Get-ItTestPackage', 'Start-Terminal', 'Start-TerminalClean', 'Stop-Terminal',
     'Reset-TerminalState', 'Backup-WtConfig', 'Restore-WtConfig', 'Get-WtProcessesForApp', 'Stop-AppInstances', 'Start-TerminalFre', 'Get-DescendantWtaIds',
     # Core (useful in tests)
     'Wait-Until', 'Test-Until', 'Invoke-Native', 'Write-ItLog', 'ConvertFrom-JsonSafe',
@@ -31,7 +31,7 @@ $publicFns = @(
     'Test-WtExecutionPolicyControllable', 'Test-WtPwshBlocksShellIntegration',
     # Ui
     'Get-UiTree', 'Find-UiElement', 'Invoke-UiElement', 'Invoke-UiClick', 'Set-UiValue', 'Get-UiValue',
-    'Wait-UiElement', 'Test-UiElementExists', 'Save-UiScreenshot', 'Get-WtWindowHwnds',
+    'Wait-UiElement', 'Test-UiElementExists', 'Save-UiScreenshot', 'Get-WtWindowHwnds', 'Test-WinAppAvailable',
     # Observe
     'Get-ItLogDir', 'Initialize-LogOffsets', 'Get-ItLogText', 'Start-WtEventListener', 'Get-WtEvents',
     'Wait-WtEvent', 'Stop-WtEventListener', 'Get-ContextBundle', 'ConvertTo-ContextText',
diff --git a/test/e2e/ItE2E/Public/Harness.ps1 b/test/e2e/ItE2E/Public/Harness.ps1
index d1bc2f12f..f1475ab0a 100644
--- a/test/e2e/ItE2E/Public/Harness.ps1
+++ b/test/e2e/ItE2E/Public/Harness.ps1
@@ -88,6 +88,21 @@ function Stop-AppInstances {
     Start-Sleep -Milliseconds 500
 }
 
+function Get-ItTestPackage {
+    <#
+    .SYNOPSIS
+        Resolve which package selector the feature/self-test suites should launch.
+        Honors the ITE2E_PACKAGE env var (Auto|Store|Dev|<PackageFamilyName>); defaults
+        to 'Auto', which prefers a fully-resolvable Store install and falls back to Dev.
+        This is the single knob that lets the suites run against a dev-only machine
+        (where only the sideload package is installed) without editing each Describe.
+    #>
+    [CmdletBinding()]
+    param()
+    if ($env:ITE2E_PACKAGE) { return $env:ITE2E_PACKAGE }
+    return 'Auto'
+}
+
 function Start-Terminal {
     <#
     .SYNOPSIS
@@ -256,7 +271,7 @@ function Start-TerminalFre {
         Backs up config for restore on Stop-Terminal.
     #>
     [CmdletBinding()]
-    param([string]$Package = 'Store', [int]$TimeoutSec = 60)
+    param([string]$Package = (Get-ItTestPackage), [int]$TimeoutSec = 60)
     return (Start-Terminal -Package $Package -ColdStart -ShowFre -Backup $true -TimeoutSec $TimeoutSec)
 }
 
diff --git a/test/e2e/ItE2E/Public/Ui.ps1 b/test/e2e/ItE2E/Public/Ui.ps1
index d81b67190..0a1199048 100644
--- a/test/e2e/ItE2E/Public/Ui.ps1
+++ b/test/e2e/ItE2E/Public/Ui.ps1
@@ -8,6 +8,23 @@ function Get-WinAppPath {
     $script:ItWinAppPath = $c; $c
 }
 
+function Test-WinAppAvailable {
+    <#
+    .SYNOPSIS
+        Non-throwing probe for the winapp (Windows App CLI) UI-automation tool.
+    .DESCRIPTION
+        Returns $true when winapp is on PATH (or already resolved), $false otherwise — unlike
+        Get-WinAppPath, which throws. Use this in a Describe readiness gate so UI-dependent
+        suites SKIP cleanly when winapp is missing instead of blowing up in BeforeAll with a
+        raw "winapp not found" exception. Install winapp via test/e2e/bootstrap.ps1.
+    #>
+    [CmdletBinding()]
+    [OutputType([bool])]
+    param()
+    if ($script:ItWinAppPath -and (Test-Path $script:ItWinAppPath)) { return $true }
+    [bool](Get-Command winapp -ErrorAction SilentlyContinue)
+}
+
 function Get-UiTarget {
     param([Parameter(Mandatory)]$App)
     if ($App.Hwnd) { return @('-w', [string]$App.Hwnd) }
diff --git a/test/e2e/README.md b/test/e2e/README.md
index 37998feae..16353b1ec 100644
--- a/test/e2e/README.md
+++ b/test/e2e/README.md
@@ -161,7 +161,11 @@ restores the backup.
 
 > **Picking the build**: pass `-Package Dev` / `-Package Store` (default `Auto`) — see
 > [Choosing the build](#choosing-the-build-dev-vs-store). Launch is package-specific
-> (AUMID), so both builds can be installed and targeted independently.
+> (AUMID), so both builds can be installed and targeted independently. The feature/self
+> -test suites don't hardcode a build — they call `Start-Terminal -Package (Get-ItTestPackage)`,
+> which honors the `ITE2E_PACKAGE` env var (`Auto`|`Store`|`Dev`|`<PackageFamilyName>`)
+> and defaults to `Auto`. So on a dev-only machine the suites resolve to the sideload
+> build automatically; set `$env:ITE2E_PACKAGE='Store'` to pin them to the store build.
 
 
 ## How it works (key facts)
diff --git a/test/e2e/selftests/ItE2E.Agent.Tests.ps1 b/test/e2e/selftests/ItE2E.Agent.Tests.ps1
index 5eeba05b8..208700817 100644
--- a/test/e2e/selftests/ItE2E.Agent.Tests.ps1
+++ b/test/e2e/selftests/ItE2E.Agent.Tests.ps1
@@ -12,7 +12,7 @@ Describe 'Agent pane + autofix' -Tag 'Agent' -Skip:(-not ($script:HasPackage -an
 
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
diff --git a/test/e2e/selftests/ItE2E.Live.Tests.ps1 b/test/e2e/selftests/ItE2E.Live.Tests.ps1
index 2e514a593..d5d78a88b 100644
--- a/test/e2e/selftests/ItE2E.Live.Tests.ps1
+++ b/test/e2e/selftests/ItE2E.Live.Tests.ps1
@@ -11,7 +11,7 @@ Describe 'ItE2E live primitives' -Tag 'Live' -Skip:(-not $script:HasPackage) {
 
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
     }
     AfterAll {
         if ($script:app) { Stop-Terminal -App $script:app }
diff --git a/test/e2e/tests/Feature.AgentChat.Tests.ps1 b/test/e2e/tests/Feature.AgentChat.Tests.ps1
index ff071d7a6..5e64722eb 100644
--- a/test/e2e/tests/Feature.AgentChat.Tests.ps1
+++ b/test/e2e/tests/Feature.AgentChat.Tests.ps1
@@ -5,13 +5,13 @@
 #   Invoke-Pester test/e2e/tests -Tag Feature
 
 BeforeDiscovery {
-    $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue))
+    $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue))
 }
 
 Describe 'Feature: agent pane chat' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot' }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot' }
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
diff --git a/test/e2e/tests/Feature.AgentPaneInteraction.Tests.ps1 b/test/e2e/tests/Feature.AgentPaneInteraction.Tests.ps1
index dd4c3ff3d..cb6af0a89 100644
--- a/test/e2e/tests/Feature.AgentPaneInteraction.Tests.ps1
+++ b/test/e2e/tests/Feature.AgentPaneInteraction.Tests.ps1
@@ -3,12 +3,12 @@
 # Agent pane slash commands (2) + Built-in agent chat (copilot) (2).
 #   Invoke-Pester test/e2e/tests -Tag Feature
 
-BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue)) }
+BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue)) }
 
 Describe 'Feature: agent pane open/hide/focus + input + slash + chat' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot' }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot' }
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
diff --git a/test/e2e/tests/Feature.AgentPopup.Tests.ps1 b/test/e2e/tests/Feature.AgentPopup.Tests.ps1
index 26b85c233..6b527d0b2 100644
--- a/test/e2e/tests/Feature.AgentPopup.Tests.ps1
+++ b/test/e2e/tests/Feature.AgentPopup.Tests.ps1
@@ -5,13 +5,13 @@
 #   Invoke-Pester test/e2e/tests -Tag Feature
 
 BeforeDiscovery {
-    $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue))
+    $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue))
 }
 
 Describe 'Feature: agent pane popup + menu' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot' }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot' }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
diff --git a/test/e2e/tests/Feature.AgentRestart.Tests.ps1 b/test/e2e/tests/Feature.AgentRestart.Tests.ps1
index 638cd9568..4e80fe4ad 100644
--- a/test/e2e/tests/Feature.AgentRestart.Tests.ps1
+++ b/test/e2e/tests/Feature.AgentRestart.Tests.ps1
@@ -3,12 +3,12 @@
 # Shift+Enter (focus) on a live session row.
 #   Invoke-Pester test/e2e/tests -Tag Feature
 
-BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue)) }
+BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue)) }
 
 Describe 'Feature: agent restart + session focus' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot' }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot' }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
diff --git a/test/e2e/tests/Feature.AutofixPane.Tests.ps1 b/test/e2e/tests/Feature.AutofixPane.Tests.ps1
index 4c8743bb1..6890b1365 100644
--- a/test/e2e/tests/Feature.AutofixPane.Tests.ps1
+++ b/test/e2e/tests/Feature.AutofixPane.Tests.ps1
@@ -5,14 +5,26 @@
 # repeated identical corrections within one session, so tests that need a FRESH card each
 # (Insert / Run / Stashed) use their own fresh terminal and trigger exactly once.
 
-BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue)) }
+BeforeDiscovery {
+    # winapp (UI-automation CLI) is required by Open-AgentPane / agent-pane assertions; gate on
+    # it too so the whole suite SKIPS cleanly when it's missing instead of throwing in BeforeAll.
+    $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue))
+    # WSL-gated cases need: the dev sideload package (OSC 9001;ShellType + the autofix
+    # shell-context fix aren't in the Store build yet), copilot for autofix, winapp for the
+    # agent pane, and a runnable WSL distro. Absent any of these the WSL Describe is skipped.
+    $script:WslReady = $false
+    $devPkg = Get-AppxPackage | Where-Object { $_.PackageFamilyName -like 'IntelligentTerminal_*' }
+    if ($devPkg -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue) -and (Get-Command wsl.exe -ErrorAction SilentlyContinue)) {
+        try { & wsl.exe -e true 2>$null; $script:WslReady = ($LASTEXITCODE -eq 0) } catch { $script:WslReady = $false }
+    }
+}
 
 # Helpers as script scriptblocks set up per-Describe in BeforeAll.
 
 Describe 'Feature: autofix card render + reject + AI correctness' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
         $script:CardShown = { ((Get-AgentPaneText -App $script:app -MaxLines 60) -match 'Run command|Insert in Terminal') }
@@ -55,7 +67,7 @@ Describe 'Feature: autofix card render + reject + AI correctness' -Tag 'Feature'
 Describe 'Feature: autofix Insert action' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
@@ -73,7 +85,7 @@ Describe 'Feature: autofix Insert action' -Tag 'Feature' -Skip:(-not $script:Rea
                 Start-Sleep -Milliseconds 400
                 Invoke-FailingCommand -App $script:app -SessionId $sid -Command $cmd | Out-Null
                 Wait-Autofix -Listener $listener -TimeoutSec 45 | Out-Null
-            } finally { Stop-WtEventListener -Listener $listener }
+            } catch { } finally { Stop-WtEventListener -Listener $listener }
             if (Test-Until -TimeoutSec 18 -IntervalSec 1 -Condition { (Get-AgentPaneText -App $script:app -MaxLines 60) -match 'Insert in Terminal' }) { $gotCard = $true; break }
         }
         if (-not $gotCard) { Set-ItResult -Skipped -Because 'autofix returned explain (no runnable-fix card) for all typos this run (LLM variance)'; return }
@@ -88,7 +100,7 @@ Describe 'Feature: autofix Insert action' -Tag 'Feature' -Skip:(-not $script:Rea
 Describe 'Feature: autofix Run action' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
@@ -104,7 +116,7 @@ Describe 'Feature: autofix Run action' -Tag 'Feature' -Skip:(-not $script:Ready)
                 Start-Sleep -Milliseconds 400
                 Invoke-FailingCommand -App $script:app -SessionId $sid -Command $cmd | Out-Null
                 Wait-Autofix -Listener $listener -TimeoutSec 45 | Out-Null
-            } finally { Stop-WtEventListener -Listener $listener }
+            } catch { } finally { Stop-WtEventListener -Listener $listener }
             if (Test-Until -TimeoutSec 18 -IntervalSec 1 -Condition { (Get-AgentPaneText -App $script:app -MaxLines 60) -match 'Run command' }) { $gotCard = $true; break }
         }
         if (-not $gotCard) { Set-ItResult -Skipped -Because 'autofix returned explain (no runnable-fix card) for all typos this run (LLM variance)'; return }
@@ -118,7 +130,7 @@ Describe 'Feature: autofix Run action' -Tag 'Feature' -Skip:(-not $script:Ready)
 Describe 'Feature: autofix on stashed pane' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
         # Pre-warm + connect, then stash so the helper is ready but the pane is hidden.
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
@@ -141,7 +153,7 @@ Describe 'Feature: autofix on stashed pane' -Tag 'Feature' -Skip:(-not $script:R
 Describe 'Feature: autofix across layout changes' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
@@ -164,7 +176,87 @@ Describe 'Feature: autofix across layout changes' -Tag 'Feature' -Skip:(-not $sc
         { Close-WtPane -App $script:app -SessionId $tab.session_id } | Should -Not -Throw
         { Get-ActivePane -App $script:app } | Should -Not -Throw
     }
-}
+}
+
+# ─────────────────────────────────────────────────────────────────────────────
+# WSL-gated: exercises OSC 9001;ShellType end-to-end and the autofix shell-context
+# fix that consumes it. Runs ONLY when a runnable WSL distro + the dev package are
+# present (the feature isn't in the Store build); otherwise the whole Describe is
+# skipped. Requires the dev package, so it targets -Package Dev explicitly.
+# ─────────────────────────────────────────────────────────────────────────────
+Describe 'Feature: autofix in a WSL pane (OSC 9001;ShellType end-to-end)' -Tag 'Feature' -Skip:(-not $script:WslReady) {
+    BeforeAll {
+        Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
+        # Dev package: the ShellType plumbing and the autofix shell-context fix live
+        # here, not in the Store build.
+        $script:app = Start-Terminal -Package Dev -PassFre $true -Settings @{ acpAgent = 'copilot'; autoFixEnabled = $true }
+
+        # Open a WSL shell pane in a fresh tab, then focus it so it's the active tab:
+        # the agent pane is per-tab, and Get-AgentPaneText / Open-AgentPane target the
+        # active tab's helper. Each tab gets its own pre-warmed helper, so autofix
+        # works on this tab.
+        $script:wsl = New-WtTab -App $script:app -Command 'wsl.exe' -Title 'wsl-autofix'
+        $script:wslSid = $script:wsl.session_id
+        $script:wslTabId = $script:wsl.tab_id
+        $script:wslWinId = $script:wsl.window_id
+        Set-WtPaneFocus -App $script:app -SessionId $script:wslSid
+
+        # Nudge a prompt so bash shell integration emits OSC 9001;ShellType at least
+        # once, then wait for the reported shell to surface through the protocol.
+        # list-panes is active-tab scoped, so query the WSL tab explicitly by id —
+        # this is robust even if focus drifts. If the shell never surfaces, the distro
+        # has no shell integration installed; the per-It guards below skip not fail.
+        Send-WtKeys -App $script:app -SessionId $script:wslSid -Keys @('Enter')
+        $script:wslShell = $null
+        Test-Until -TimeoutSec 30 -IntervalSec 1 -Condition {
+            $p = Get-WtPanes -App $script:app -TabId $script:wslTabId -WindowId $script:wslWinId |
+                Where-Object { $_.session_id -eq $script:wslSid }
+            if ($p -and ($p.shell -match '^(?i)wsl:')) { $script:wslShell = $p.shell; $true } else { $false }
+        } | Out-Null
+
+        # Agent pane on the (now active) WSL tab so autofix cards render here.
+        Open-AgentPane -App $script:app | Out-Null
+        Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
+    }
+    AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
+
+    It 'WSL pane self-reports its shell as wsl:<distro> through the protocol' {
+        if (-not $script:wslShell) {
+            Set-ItResult -Skipped -Because 'WSL pane never reported a wsl: shell (shell integration not installed in this distro)'
+            return
+        }
+        # Proves OSC 9001;ShellType -> adaptDispatch -> Terminal -> ControlCore ->
+        # PaneInfo -> COM JSON, including the distro name surviving the ';' split.
+        $script:wslShell | Should -Match '^(?i)wsl:\S'
+    }
+
+    It 'Autofix suggests a Linux/bash fix (not PowerShell) in a WSL pane' {
+        if (-not $script:wslShell) {
+            Set-ItResult -Skipped -Because 'WSL shell integration not installed; autofix has no WSL shell context to read'
+            return
+        }
+        # bash-typos whose correct form is unmistakably Linux (ls/grep/cat), so the AI
+        # oracle can tell a bash fix from a PowerShell one (Get-ChildItem etc.). The
+        # whole point of the fix under test: with shell=wsl:<distro> in the prompt the
+        # agent must NOT fall back to PowerShell syntax.
+        $typos = @('sl -la', 'lll', 'grpe root /etc/hostname', 'caat /etc/hostname')
+        $gotCard = $false
+        foreach ($cmd in $typos) {
+            $listener = Start-WtEventListener -App $script:app
+            try {
+                Start-Sleep -Milliseconds 400
+                Invoke-FailingCommand -App $script:app -SessionId $script:wslSid -Command $cmd | Out-Null
+                Wait-Autofix -Listener $listener -TimeoutSec 45 | Out-Null
+            } catch { } finally { Stop-WtEventListener -Listener $listener }
+            if (Test-Until -TimeoutSec 18 -IntervalSec 1 -Condition { (Get-AgentPaneText -App $script:app -MaxLines 60) -match 'Run command|Insert in Terminal' }) { $gotCard = $true; break }
+        }
+        if (-not $gotCard) {
+            Set-ItResult -Skipped -Because 'autofix returned explain (no runnable-fix card) for all typos this run (LLM variance)'
+            return
+        }
+        Assert-AI -Claim 'The suggested fix command uses Linux/bash shell syntax (e.g. ls, grep, cat, forward-slash paths). It is NOT a Windows PowerShell command (no Get-ChildItem / Select-String / cmdlet-style Verb-Noun).' -Context (Get-AgentPaneText -App $script:app -MaxLines 60)
+    }
+}
 
 
 
diff --git a/test/e2e/tests/Feature.FreExecutionPolicy.Tests.ps1 b/test/e2e/tests/Feature.FreExecutionPolicy.Tests.ps1
index e61e3ed95..c57aad7e3 100644
--- a/test/e2e/tests/Feature.FreExecutionPolicy.Tests.ps1
+++ b/test/e2e/tests/Feature.FreExecutionPolicy.Tests.ps1
@@ -34,6 +34,9 @@ BeforeDiscovery {
     # of the suite cleanly skipping.
     $script:DevReady = $false
     try { $null = Resolve-ItApp -Package Dev -ErrorAction Stop; $script:DevReady = $true } catch { $script:DevReady = $false }
+    # winapp drives the FRE overlay via UIA; without it BeforeAll would throw, so fold it into
+    # the gate and skip the suite cleanly instead.
+    $script:DevReady = $script:DevReady -and (Test-WinAppAvailable)
     # A Group Policy execution-policy override (MachinePolicy/UserPolicy) outranks the HKCU
     # CurrentUser scope these tests force, making the FRE verdict non-deterministic — skip the
     # whole suite when one is in effect rather than assert against an uncontrollable policy.
diff --git a/test/e2e/tests/Feature.FreFlow.Tests.ps1 b/test/e2e/tests/Feature.FreFlow.Tests.ps1
index d1135f88f..4fc8a908f 100644
--- a/test/e2e/tests/Feature.FreFlow.Tests.ps1
+++ b/test/e2e/tests/Feature.FreFlow.Tests.ps1
@@ -3,14 +3,14 @@
 # (the FRE is a XAML overlay with AutomationId buttons NextButton / SaveButton).
 #   Invoke-Pester test/e2e/tests -Tag Feature
 
-BeforeDiscovery { $script:Ready = [bool](Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) }
+BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command winapp -ErrorAction SilentlyContinue)) }
 
 Describe 'Feature §0 FRE overlay flow' -Tag 'Feature' -Skip:(-not $script:Ready) {
 
     Context 'FRE opens' {
         It 'FRE opens correctly (Welcome page shows on a fresh profile)' {
             Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-            $app = Start-TerminalFre -Package Store
+            $app = Start-TerminalFre -Package (Get-ItTestPackage)
             try {
                 Test-UiElementExists -App $app -Selector 'WelcomePage' -TimeoutSec 10 | Should -BeTrue
                 Test-UiElementExists -App $app -Selector 'NextButton' -TimeoutSec 5 | Should -BeTrue
@@ -22,7 +22,7 @@ Describe 'Feature §0 FRE overlay flow' -Tag 'Feature' -Skip:(-not $script:Ready
     Context 'FRE privacy/help link' {
         It 'FRE privacy / help link is present on the welcome page' {
             Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-            $app = Start-TerminalFre -Package Store
+            $app = Start-TerminalFre -Package (Get-ItTestPackage)
             try {
                 $tree = Get-UiTree -App $app -Depth 8
                 $tree | Should -Match 'Learn more|privacy|Privacy'
@@ -34,7 +34,7 @@ Describe 'Feature §0 FRE overlay flow' -Tag 'Feature' -Skip:(-not $script:Ready
     Context 'FRE completion' {
         It 'FRE can be completed (Next -> Save dismisses the overlay and marks complete)' {
             Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-            $app = Start-TerminalFre -Package Store
+            $app = Start-TerminalFre -Package (Get-ItTestPackage)
             try {
                 Test-FreShowing -App $app | Should -BeTrue
                 Invoke-UiElement -App $app -Selector 'NextButton' -TimeoutSec 10 | Out-Null
@@ -52,7 +52,7 @@ Describe 'Feature §0 FRE overlay flow' -Tag 'Feature' -Skip:(-not $script:Ready
 
         It 'FRE save progress / completion leaves a usable terminal (settings valid)' {
             Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-            $app = Start-TerminalFre -Package Store
+            $app = Start-TerminalFre -Package (Get-ItTestPackage)
             try {
                 Invoke-UiElement -App $app -Selector 'NextButton' -TimeoutSec 10 | Out-Null
                 Wait-UiElement -App $app -Selector 'SaveButton' -TimeoutSec 10 | Out-Null
@@ -71,12 +71,12 @@ Describe 'Feature §0 FRE overlay flow' -Tag 'Feature' -Skip:(-not $script:Ready
     Context 'FRE close safety' {
         It 'FRE can be closed safely (closing the window mid-FRE leaves settings valid)' {
             Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-            $app = Start-TerminalFre -Package Store
+            $app = Start-TerminalFre -Package (Get-ItTestPackage)
             Test-FreShowing -App $app | Should -BeTrue
             # Closing the window during FRE must not corrupt settings/state.
             Stop-Terminal -App $app
             # Relaunch (FRE was never completed, so settings.json must still parse).
-            $app2 = Start-Terminal -Package Store -PassFre $true
+            $app2 = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
             try {
                 (Get-WtSettingsObject -App $app2) | Should -Not -BeNullOrEmpty
             }
diff --git a/test/e2e/tests/Feature.Packaging.Tests.ps1 b/test/e2e/tests/Feature.Packaging.Tests.ps1
index 1ac3d4258..1d3758b13 100644
--- a/test/e2e/tests/Feature.Packaging.Tests.ps1
+++ b/test/e2e/tests/Feature.Packaging.Tests.ps1
@@ -4,12 +4,17 @@
 # Maps to checklist items (auto): packaged wta present, packaged identity, WT_COM_CLSID,
 # wtcli list-panes/capture-pane/send-keys/listen, master+helper start, logs+version dir.
 
-BeforeDiscovery { $script:Ready = [bool](Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) }
+BeforeDiscovery {
+    $script:Ready = [bool](Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' })
+    # §10 opens the agent pane (UI automation) so it additionally needs winapp; §9 is
+    # pure protocol/packaging and runs without it.
+    $script:UiReady = $script:Ready -and [bool](Get-Command winapp -ErrorAction SilentlyContinue)
+}
 
 Describe 'Feature §9 Packaging + protocol' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
@@ -73,10 +78,10 @@ Describe 'Feature §9 Packaging + protocol' -Tag 'Feature' -Skip:(-not $script:R
     }
 }
 
-Describe 'Feature §10 Diagnostics + logging' -Tag 'Feature' -Skip:(-not $script:Ready) {
+Describe 'Feature §10 Diagnostics + logging' -Tag 'Feature' -Skip:(-not $script:UiReady) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
     }
diff --git a/test/e2e/tests/Feature.SessionList.Tests.ps1 b/test/e2e/tests/Feature.SessionList.Tests.ps1
index c09270b66..2b879dc79 100644
--- a/test/e2e/tests/Feature.SessionList.Tests.ps1
+++ b/test/e2e/tests/Feature.SessionList.Tests.ps1
@@ -3,12 +3,12 @@
 # (the agent-pane session-management view). Deterministic where possible; AI only for
 # semantic checks.
 
-BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue)) }
+BeforeDiscovery { $script:Ready = [bool]((Get-AppxPackage | Where-Object { $_.Name -like '*IntelligentTerminal*' }) -and (Get-Command copilot -ErrorAction SilentlyContinue) -and (Get-Command winapp -ErrorAction SilentlyContinue)) }
 
 Describe 'Feature: session list + view switching + focus/restore' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true -Settings @{ acpAgent = 'copilot' }
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true -Settings @{ acpAgent = 'copilot' }
         Open-AgentPane -App $script:app | Out-Null
         Wait-AgentReady -App $script:app -TimeoutSec 60 | Out-Null
         # Seed a live session with a known marker so a row exists.
diff --git a/test/e2e/tests/Feature.Settings.Tests.ps1 b/test/e2e/tests/Feature.Settings.Tests.ps1
index c3f6f5617..ba4b2fdcd 100644
--- a/test/e2e/tests/Feature.Settings.Tests.ps1
+++ b/test/e2e/tests/Feature.Settings.Tests.ps1
@@ -9,7 +9,7 @@ BeforeDiscovery { $script:Ready = [bool](Get-AppxPackage | Where-Object { $_.Nam
 Describe 'Feature §1 Settings > AI Agents' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
@@ -60,7 +60,7 @@ Describe 'Feature §1 Settings > AI Agents' -Tag 'Feature' -Skip:(-not $script:R
 Describe 'Feature §0 FRE settings, positions, auto-error, session mgmt' -Tag 'Feature' -Skip:(-not $script:Ready) {
     BeforeAll {
         Import-Module (Join-Path $PSScriptRoot '..\ItE2E\ItE2E.psd1') -Force
-        $script:app = Start-Terminal -Package Store -PassFre $true
+        $script:app = Start-Terminal -Package (Get-ItTestPackage) -PassFre $true
     }
     AfterAll { if ($script:app) { Stop-Terminal -App $script:app } }
 
diff --git a/tools/wta/src/protocol/acp/client.rs b/tools/wta/src/protocol/acp/client.rs
index 5b62b25f4..dadbdfe7f 100644
--- a/tools/wta/src/protocol/acp/client.rs
+++ b/tools/wta/src/protocol/acp/client.rs
@@ -985,11 +985,29 @@ fn process_image_name(_pid: u32) -> Option<String> {
     None
 }
 
-/// Resolve the canonical shell exe from an active-pane JSON object's `pid`
-/// field (already present in `get_active_pane`/`get_panes` responses). The
-/// agent gets this as the `shell` field — the sole shell-type signal, since
-/// the WT profile *name* (which the user can rename) is no longer shipped.
+/// Resolve the shell identity for an active-pane JSON object. The agent gets
+/// this as the `shell` field — the shell-type signal that drives PowerShell vs
+/// bash vs cmd syntax in any fix command it suggests.
+///
+/// Resolution order:
+///   1. The `shell` field reported by shell integration via `OSC 9001;ShellType`
+///      (e.g. `pwsh`, `powershell`, `bash`, `wsl:Ubuntu`). This is the only
+///      signal that survives a nested shell — `pwsh` → `wsl` → `exit` reports
+///      `wsl:<distro>` while inside WSL and `pwsh` again after exit, because the
+///      shell re-emits it on every prompt. The pid-based fallback below can't
+///      see this: the pane's host process stays `wsl.exe`/`pwsh.exe` regardless
+///      of which shell is actually drawing the prompt.
+///   2. Otherwise, the canonical shell exe from the pane's `pid` (covers panes
+///      without shell integration installed, or before the first prompt).
 fn shell_from_active(active: &serde_json::Value) -> Option<String> {
+    if let Some(shell) = active
+        .get("shell")
+        .and_then(|v| v.as_str())
+        .map(str::trim)
+        .filter(|s| !s.is_empty())
+    {
+        return Some(shell.to_string());
+    }
     active
         .get("pid")
         .and_then(|v| v.as_u64())
@@ -3550,6 +3568,25 @@ mod tests {
         assert_eq!(shell_from_active(&serde_json::json!({})), None);
     }
 
+    /// The `shell` field reported via `OSC 9001;ShellType` wins over the
+    /// pid-based fallback — even when a real pid is present. This is the
+    /// nested-shell case (`pwsh` → `wsl` → bash): the pane's host process is
+    /// still pwsh/wsl.exe, but the prompt is drawn by bash, so the OSC-reported
+    /// `wsl:Ubuntu` must reach the agent. Platform-independent (no pid lookup).
+    #[test]
+    fn shell_from_active_prefers_osc_reported_shell() {
+        // Reported shell wins over a live pid.
+        let pane = serde_json::json!({ "pid": std::process::id(), "shell": "wsl:Ubuntu" });
+        assert_eq!(shell_from_active(&pane), Some("wsl:Ubuntu".to_string()));
+
+        // Empty/whitespace reported shell is ignored; falls back to pid (or None).
+        assert_eq!(
+            shell_from_active(&serde_json::json!({ "shell": "  ", "pid": 0 })),
+            None
+        );
+        assert_eq!(shell_from_active(&serde_json::json!({ "shell": "" })), None);
+    }
+
     /// Helper-only: round-trip a `_meta` blob through `inject_wta_pane_meta`
     /// and report the `pane_session_id` that the master would see in
     /// `extract_wta_meta`. Returns `None` when the meta is empty after