diff --git a/plugin/README.md b/plugin/README.md
index 1483d7f..d4d2a8e 100644
--- a/plugin/README.md
+++ b/plugin/README.md
@@ -190,6 +190,11 @@ copilot plugin list       # tokeneconomizer@tokeneconomizer ... (enabled)
 
 Copilot loads the plugin from the clone directly, without copying it.
 
+On Windows, its hooks and slash commands use PowerShell; Git Bash is not required.
+From a PowerShell terminal in the clone, run `.\plugin\scripts\te.ps1 --host copilot status`.
+The launcher honors `TE_PYTHON`, then looks for `python3`, `python`, or `py`, preferring
+interpreters outside WindowsApps.
+
 **2. Check it.** In Copilot's interactive mode, type `/tokeneconomizer:status`. Each slash command
 is a model turn, and Copilot asks before running the plugin's script; choose **Yes**. Slash
 commands work only in interactive mode; the plugin's notices also appear under `copilot -p`.
@@ -211,7 +216,11 @@ start says so. `/tokeneconomizer:toolprune restore` turns the server back on, an
 `toolprune measure` shows the difference with no model call.
 
 From a terminal, inside the repository: `~/.tokeneconomizer/bin/te --host copilot <command>` (the
-launcher appears after the first session). A turn that is still stuck after the loop guard's
+launcher appears after the first session). In PowerShell, use
+`& "$HOME\.tokeneconomizer\bin\te.ps1" --host copilot <command>` instead (or the same path under
+`$env:TOKENECONOMIZER_HOME` when set). Session-start and prompt hooks create or repair the launchers,
+so an open session picks up the PowerShell launcher on its next prompt after updating.
+A turn that is still stuck after the loop guard's
 redirect shows "● TokenEconomizer: …" in the conversation (and on stdout under `copilot -p`); press
 **Esc** twice to interrupt it, or Ctrl+C to end a `copilot -p` run.
 
diff --git a/plugin/hooks/copilot-hooks.json b/plugin/hooks/copilot-hooks.json
index 15c8fd8..898d5bd 100644
--- a/plugin/hooks/copilot-hooks.json
+++ b/plugin/hooks/copilot-hooks.json
@@ -7,6 +7,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 15
           }
         ]
@@ -18,6 +19,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 20
           }
         ]
@@ -29,6 +31,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 60
           }
         ]
@@ -40,6 +43,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 60
           }
         ]
@@ -51,6 +55,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 10
           }
         ]
@@ -62,6 +67,7 @@
           {
             "type": "command",
             "command": "\"${PLUGIN_ROOT}/scripts/te-hook\" --host copilot",
+            "windows": "& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te-hook.ps1') --host copilot",
             "timeout": 10
           }
         ]
diff --git a/plugin/scripts/te-hook.ps1 b/plugin/scripts/te-hook.ps1
new file mode 100644
index 0000000..877910c
--- /dev/null
+++ b/plugin/scripts/te-hook.ps1
@@ -0,0 +1,6 @@
+if ($MyInvocation.ExpectingInput) {
+    $input | & "$PSScriptRoot\te.ps1" -Hook @args
+} else {
+    & "$PSScriptRoot\te.ps1" -Hook @args
+}
+exit $LASTEXITCODE
diff --git a/plugin/scripts/te.ps1 b/plugin/scripts/te.ps1
new file mode 100644
index 0000000..89bbf29
--- /dev/null
+++ b/plugin/scripts/te.ps1
@@ -0,0 +1,51 @@
+param([switch]$Hook)
+
+$env:PYTHONUTF8 = '1'
+$OutputEncoding = [Console]::InputEncoding = [Console]::OutputEncoding = New-Object System.Text.UTF8Encoding
+$mode = if ($Hook) { 'hook' } else { 'cli' }
+$payload = if ($Hook) {
+    if ($MyInvocation.ExpectingInput) { $input -join "`n" } else { [Console]::In.ReadToEnd() }
+}
+$candidates = @(
+    foreach ($name in @($env:TE_PYTHON, 'python3', 'python', 'py')) {
+        if ($name) {
+            Get-Command $name -CommandType Application -All -ErrorAction SilentlyContinue
+        }
+    }
+)
+$python = $candidates | Where-Object { $_.Source -notlike '*\WindowsApps\*' } | Select-Object -First 1
+if (-not $python) {
+    foreach ($candidate in $candidates) {
+        & $candidate.Source -c pass *> $null
+        if ($LASTEXITCODE -eq 0) { $python = $candidate; break }
+    }
+}
+if (-not $python) {
+    $message = 'te: no Python on PATH (set TE_PYTHON)'
+    if ($Hook) {
+        $root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else {
+            Join-Path $HOME '.tokeneconomizer'
+        }
+        try {
+            [IO.Directory]::CreateDirectory($root) | Out-Null
+            [IO.File]::AppendAllText((Join-Path $root 'errors.log'), "$message`n")
+        } catch [IO.IOException] {
+            [Console]::Error.WriteLine($_.Exception.Message)
+        } catch [UnauthorizedAccessException] {
+            [Console]::Error.WriteLine($_.Exception.Message)
+        }
+        '{}'
+        exit 0
+    }
+    [Console]::Error.WriteLine($message)
+    exit 1
+}
+$pythonArgs = @()
+if ($python.Name -eq 'py.exe' -or $python.Name -eq 'py') { $pythonArgs += '-3' }
+$pythonArgs += @((Join-Path $PSScriptRoot 'te_bootstrap.py'), $mode)
+if ($Hook) {
+    $payload | & $python.Source @pythonArgs @args
+} else {
+    & $python.Source @pythonArgs @args
+}
+exit $LASTEXITCODE
diff --git a/plugin/slash-commands/config.md b/plugin/slash-commands/config.md
index 913ede6..fe4c3d5 100644
--- a/plugin/slash-commands/config.md
+++ b/plugin/slash-commands/config.md
@@ -3,7 +3,16 @@ description: Show or change TokenEconomizer's settings - turn each mechanism on
 argument-hint: "[show | set KEY=VALUE ... [--global] | unset KEY ... [--global]]"
 ---
 The arguments I typed after the command are: "$ARGUMENTS" (it shows every setting when there are none).
-Run this exact command with the Bash tool, then show me its output verbatim in a code block:
+Run the command for this shell, then show me its output verbatim in a code block.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path config $ARGUMENTS
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" config $ARGUMENTS
diff --git a/plugin/slash-commands/facts.md b/plugin/slash-commands/facts.md
index 9bfc20e..9623871 100644
--- a/plugin/slash-commands/facts.md
+++ b/plugin/slash-commands/facts.md
@@ -1,7 +1,16 @@
 ---
 description: Earlier name of /tokeneconomizer:microskills - show the repository facts TokenEconomizer injects
 ---
-Run this exact command with the Bash tool, then show me its output verbatim in a code block, with no commentary:
+Run the command for this shell, then show me its output verbatim in a code block, with no commentary.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path microskills
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" microskills
diff --git a/plugin/slash-commands/microskills.md b/plugin/slash-commands/microskills.md
index 4f65110..5bc2ae4 100644
--- a/plugin/slash-commands/microskills.md
+++ b/plugin/slash-commands/microskills.md
@@ -1,7 +1,16 @@
 ---
 description: Show the repository facts (micro-skills) TokenEconomizer learned and injects at session start
 ---
-Run this exact command with the Bash tool, then show me its output verbatim in a code block, with no commentary:
+Run the command for this shell, then show me its output verbatim in a code block, with no commentary.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path microskills
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" microskills
diff --git a/plugin/slash-commands/repos.md b/plugin/slash-commands/repos.md
index e0a4778..99f2141 100644
--- a/plugin/slash-commands/repos.md
+++ b/plugin/slash-commands/repos.md
@@ -3,7 +3,16 @@ description: List every repository TokenEconomizer keeps state for, or merge one
 argument-hint: "[list | migrate | merge KEY [INTO]]"
 ---
 The arguments I typed after the command are: "$ARGUMENTS" (it lists the repositories when there are none).
-Run this exact command with the Bash tool, then show me its output verbatim in a code block:
+Run the command for this shell, then show me its output verbatim in a code block.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path repos $ARGUMENTS
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" repos $ARGUMENTS
diff --git a/plugin/slash-commands/status.md b/plugin/slash-commands/status.md
index 8f01053..34991ef 100644
--- a/plugin/slash-commands/status.md
+++ b/plugin/slash-commands/status.md
@@ -1,7 +1,16 @@
 ---
 description: Show what TokenEconomizer has learned for this repository and what it has done
 ---
-Run this exact command with the Bash tool, then show me its output verbatim in a code block. Add nothing unless the output contains a warning, in which case explain the warning in one sentence.
+Run the command for this shell, then show me its output verbatim in a code block. Add nothing unless the output contains a warning, in which case explain the warning in one sentence.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path status
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" status
diff --git a/plugin/slash-commands/toolprune.md b/plugin/slash-commands/toolprune.md
index c757e9b..afa3adf 100644
--- a/plugin/slash-commands/toolprune.md
+++ b/plugin/slash-commands/toolprune.md
@@ -3,7 +3,16 @@ description: Review the tools TokenEconomizer left out of this repository's sess
 argument-hint: "[show | apply [TOOL ...] | restore [TOOL ...] | refresh-catalog | measure]"
 ---
 The arguments I typed after the command are: "$ARGUMENTS" (it shows the proposal when there are none).
-Run this exact command with the Bash tool, then show me its output verbatim in a code block:
+Run the command for this shell, then show me its output verbatim in a code block.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path toolprune $ARGUMENTS
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" toolprune $ARGUMENTS
diff --git a/plugin/slash-commands/untool.md b/plugin/slash-commands/untool.md
index a5fc7b9..a6649c8 100644
--- a/plugin/slash-commands/untool.md
+++ b/plugin/slash-commands/untool.md
@@ -3,7 +3,16 @@ description: Earlier name of /tokeneconomizer:toolprune - review the deny list,
 argument-hint: "[show | apply [TOOL ...] | restore [TOOL ...] | refresh-catalog | measure]"
 ---
 The arguments I typed after the command are: "$ARGUMENTS" (it shows the proposal when there are none).
-Run this exact command with the Bash tool, then show me its output verbatim in a code block:
+Run the command for this shell, then show me its output verbatim in a code block.
+
+In Copilot CLI on Windows, use the PowerShell tool:
+
+```powershell
+$root = if ($env:TOKENECONOMIZER_HOME) { $env:TOKENECONOMIZER_HOME } else { Join-Path $HOME '.tokeneconomizer' }
+& (Join-Path $root 'bin\te.ps1') --host copilot --cwd (Get-Location).Path toolprune $ARGUMENTS
+```
+
+Otherwise, use the Bash tool:
 
 ```
 te="${CLAUDE_PLUGIN_ROOT}/scripts/te"; [ -x "$te" ] || te="${TOKENECONOMIZER_HOME:-$HOME/.tokeneconomizer}/bin/te"; "$te" --cwd "$(pwd)" toolprune $ARGUMENTS
diff --git a/tests/test_plugin_package.py b/tests/test_plugin_package.py
index 011f962..0842c6e 100644
--- a/tests/test_plugin_package.py
+++ b/tests/test_plugin_package.py
@@ -70,6 +70,7 @@ def test_hook_files_run_the_launcher_on_every_event(name, host):
             assert f"--host {host}" in h["command"]
         if host == "copilot":
             assert h["command"].startswith('"${PLUGIN_ROOT}/scripts/te-hook"')
+            assert "te-hook.ps1" in h["windows"] and "--host copilot" in h["windows"]
         if host == "codex":
             assert h["commandWindows"] == CODEX_WINDOWS
             if event == "SessionEnd":
@@ -143,6 +144,95 @@ def _hook_env(tmp_path, **extra):
     return env
 
 
+POWERSHELLS = [p for p in (shutil.which("powershell"), shutil.which("pwsh")) if p]
+
+
+@pytest.mark.parametrize("shell", POWERSHELLS or [None])
+@pytest.mark.parametrize("event", ["SessionStart", "UserPromptSubmit"])
+@pytest.mark.skipif(os.name != "nt" or not POWERSHELLS, reason="native Windows PowerShell")
+def test_powershell_hook_and_slash_commands_without_git_bash(tmp_path, shell, event):
+    work = tmp_path / "work space \u00e9"
+    work.mkdir()
+    scripts = tmp_path / "plugin's copy" / "scripts"
+    shutil.copytree(os.path.join(PLUGIN, "scripts"), scripts,
+                    ignore=shutil.ignore_patterns("__pycache__"))
+    env = _hook_env(tmp_path, TE_PYTHON=sys.executable, TE_CORE_PATH=REPO,
+                    COPILOT_PLUGIN_ROOT=str(scripts.parent))
+    env["PATH"] = os.path.dirname(sys.executable)
+    command = next(_commands(_json(PLUGIN, "hooks", "copilot-hooks.json")))[2]["windows"]
+
+    def run(script, payload=None):
+        return subprocess.run([shell, "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command",
+                               script], input=payload, capture_output=True, encoding="utf-8",
+                              env=env, cwd=work, timeout=60)
+
+    payload = json.dumps({"hook_event_name": event, "session_id": "s",
+                          "cwd": str(work), "source": "new"}, ensure_ascii=False)
+    out = run(command, payload)
+    assert out.returncode == 0 and json.loads(out.stdout) == {}, out.stderr
+    errors = tmp_path / "home" / "errors.log"
+    assert not errors.exists(), errors.read_text(encoding="utf-8")
+    sessions = list((tmp_path / "home" / "repos").glob("*/copilot/sessions/s.json"))
+    assert sessions, (out.stdout, out.stderr)
+    assert json.loads(sessions[0].read_text(encoding="utf-8"))["cwd"] == str(work)
+    for name in ("status", "config", "repos", "microskills", "facts", "toolprune", "untool"):
+        text = open(os.path.join(PLUGIN, "slash-commands", name + ".md"), encoding="utf-8").read()
+        script = re.search(r"```powershell\n(.*?)\n```", text, re.S).group(1)
+        out = run(script.replace("$ARGUMENTS", ""))
+        assert out.returncode == 0 and out.stdout.strip(), (name, out.stderr)
+    assert (tmp_path / "home" / "bin" / "te.ps1").exists()
+    config = open(os.path.join(PLUGIN, "slash-commands", "config.md"), encoding="utf-8").read()
+    script = re.search(r"```powershell\n(.*?)\n```", config, re.S).group(1)
+    out = run(script.replace("$ARGUMENTS", "set loopguard=off"))
+    assert out.returncode == 0, out.stderr
+    settings = list((tmp_path / "home" / "repos").glob("*/config.json"))
+    assert settings and json.loads(settings[0].read_text())["loopguard"] == "off"
+    out = run(f"'{payload.replace(chr(39), chr(39) * 2)}' | {command}")
+    assert out.returncode == 0 and json.loads(out.stdout) == {}, out.stderr
+    env.update(PATH="", TE_PYTHON=str(tmp_path / "missing.exe"))
+    out = run(command, payload)
+    assert out.returncode == 0 and json.loads(out.stdout) == {}, out.stderr
+    assert "no Python" in (tmp_path / "home" / "errors.log").read_text()
+    out = run("& (Join-Path $env:COPILOT_PLUGIN_ROOT 'scripts\\te.ps1') status")
+    assert out.returncode == 1 and "no Python" in out.stderr
+
+
+@pytest.mark.parametrize("shell", POWERSHELLS or [None])
+@pytest.mark.skipif(os.name != "nt" or not POWERSHELLS, reason="native Windows PowerShell")
+def test_powershell_launcher_forwards_arguments_and_exit_code(tmp_path, shell):
+    scripts = tmp_path / "plugin's scripts"
+    scripts.mkdir()
+    shutil.copy(os.path.join(PLUGIN, "scripts", "te.ps1"), scripts)
+    (scripts / "te_bootstrap.py").write_text(
+        "import json, sys\nprint(json.dumps(sys.argv[1:]))\nsys.exit(7)\n")
+    command = "& '%s' --host copilot --cwd 'a path' config set 'paid_model=a&b'; exit $LASTEXITCODE" % (
+        str(scripts / "te.ps1").replace("'", "''"))
+    out = subprocess.run([shell, "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command", command],
+                         capture_output=True, encoding="utf-8",
+                         env=_hook_env(tmp_path, TE_PYTHON=sys.executable), timeout=60)
+    assert out.returncode == 7, out.stderr
+    assert json.loads(out.stdout) == ["cli", "--host", "copilot", "--cwd", "a path",
+                                     "config", "set", "paid_model=a&b"]
+    winapps = tmp_path / "Microsoft" / "WindowsApps"
+    winapps.mkdir(parents=True)
+    marker = tmp_path / "alias_called"
+    (winapps / "python3.cmd").write_text(f'@echo alias>"{marker}"\n@exit /b 1\n')
+    env = _hook_env(tmp_path, TE_PYTHON="",
+                    PATH=os.pathsep.join((str(winapps), os.path.dirname(sys.executable))))
+    out = subprocess.run([shell, "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command", command],
+                         capture_output=True, encoding="utf-8", env=env, timeout=60)
+    assert out.returncode == 7, out.stderr
+    assert json.loads(out.stdout)[0] == "cli"
+    assert not marker.exists()
+    (winapps / "python3.cmd").write_text(f'@"{sys.executable}" %*\n')
+    env["PATH"] = str(winapps)
+    command = "& '%s' status; exit $LASTEXITCODE" % str(scripts / "te.ps1").replace("'", "''")
+    out = subprocess.run([shell, "-NoProfile", "-ExecutionPolicy", "Bypass", "-Command", command],
+                         capture_output=True, encoding="utf-8", env=env, timeout=60)
+    assert out.returncode == 7, out.stderr
+    assert json.loads(out.stdout) == ["cli", "status"]
+
+
 def test_the_launcher_runs_the_dispatcher_from_the_checkout(tmp_path):
     work = tmp_path / "work"
     work.mkdir()
diff --git a/tokeneconomizer/plugin/controller.py b/tokeneconomizer/plugin/controller.py
index cfef0b2..d7fa25a 100644
--- a/tokeneconomizer/plugin/controller.py
+++ b/tokeneconomizer/plugin/controller.py
@@ -95,16 +95,17 @@ def handle(self):
         self.ctx.settle()
         self.cfg = self.ctx.config
         event = self.p.get("hook_event_name") or ""
+        if event in ("SessionStart", "UserPromptSubmit"):
+            try:
+                ensure_launcher(self.ctx.env)
+            except OSError:
+                self._record_error()
         handler = self.handler(event)
         return hookqueue.run(self, event, handler) if handler else {}
 
     # ---- SessionStart -----------------------------------------------------------------
     def session_start(self):
         source = self.p.get("source") or "startup"
-        try:
-            ensure_launcher(self.ctx.env)
-        except OSError:
-            pass
         s = self._session()
         s["source"] = source
         s.setdefault("cwd", self.host.cwd(self.p, self.ctx.env))
diff --git a/tokeneconomizer/plugin/paths.py b/tokeneconomizer/plugin/paths.py
index d52ae56..ea7bb8a 100644
--- a/tokeneconomizer/plugin/paths.py
+++ b/tokeneconomizer/plugin/paths.py
@@ -53,15 +53,16 @@ def launcher_path(env=None):
 
 
 def ensure_launcher(env=None):
-    """Keep `<state root>/bin/te` pointing at this plugin's `te`. Returns its path, or None.
+    """Keep `bin/te` (and `bin/te.ps1` on Windows) pointing at this plugin. Returns te or None.
 
     A slash command has to name the CLI's path. Claude Code substitutes `${CLAUDE_PLUGIN_ROOT}`
     into a command's text; the Copilot CLI substitutes nothing but `$ARGUMENTS` (1.0.83:
     `${CLAUDE_PLUGIN_ROOT}`, `${PLUGIN_ROOT}`, `${COPILOT_PLUGIN_ROOT}`, `{{plugin_root}}` all
-    arrive literally), and its shell exports none of them. So every hook session start writes
-    this one-line launcher, the commands fall back to it, and a person on any host has a stable
-    `te` to run. The plugin's location comes from the bootstrap (`TE_PLUGIN_ROOT`); the file is
-    rewritten only when it changes, as an installed copy's path does across updates."""
+    arrive literally), and its shell exports none of them. Session-start and prompt hooks keep
+    these launchers current, including in sessions already open when the plugin was updated.
+    The commands fall back to them, and a person on any host has a stable `te` to run. The plugin's
+    location comes from the bootstrap (`TE_PLUGIN_ROOT`); each file is rewritten only when it
+    changes, as an installed copy's path does across updates."""
     import shlex
     env = os.environ if env is None else env
     plugin = env.get("TE_PLUGIN_ROOT")
@@ -71,18 +72,23 @@ def ensure_launcher(env=None):
     path = launcher_path(env)
     body = ("#!/bin/sh\n# Written by the TokenEconomizer plugin at session start: its `te` "
             "command line.\nexec %s \"$@\"\n" % shlex.quote(target))
-    try:
-        with open(path, encoding="utf-8") as fh:
-            if fh.read() == body:
-                return path
-    except OSError:
-        pass
-    os.makedirs(os.path.dirname(path), exist_ok=True)
-    tmp = "%s.%d.tmp" % (path, os.getpid())
-    with open(tmp, "w", encoding="utf-8") as fh:
-        fh.write(body)
-    os.chmod(tmp, 0o700)
-    os.replace(tmp, path)
+    launchers = {path: body}
+    if os.name == "nt":
+        launchers[path + ".ps1"] = "& '%s' @args\nexit $LASTEXITCODE\n" % (
+            target.replace("'", "''") + ".ps1")
+    for launcher, body in launchers.items():
+        try:
+            with open(launcher, encoding="utf-8") as fh:
+                if fh.read() == body:
+                    continue
+        except OSError:
+            pass
+        os.makedirs(os.path.dirname(launcher), exist_ok=True)
+        tmp = "%s.%d.tmp" % (launcher, os.getpid())
+        with open(tmp, "w", encoding="utf-8") as fh:
+            fh.write(body)
+        os.chmod(tmp, 0o700)
+        os.replace(tmp, launcher)
     return path