diff --git a/cli/entrypoints.py b/cli/entrypoints.py
index 3092d2d9..8e5d0a74 100644
--- a/cli/entrypoints.py
+++ b/cli/entrypoints.py
@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import os
+import shutil
 import subprocess
 import sys
 from collections.abc import Mapping, Sequence
@@ -153,7 +154,19 @@ def launch_claude(argv: Sequence[str] | None = None) -> None:
         raise SystemExit(1)
 
     args = list(sys.argv[1:] if argv is None else argv)
-    command = [settings.claude_cli_bin, *args]
+    claude_command = shutil.which(settings.claude_cli_bin)
+    if claude_command is None:
+        print(
+            f"Could not find Claude Code command: {settings.claude_cli_bin}",
+            file=sys.stderr,
+        )
+        print(
+            "Install Claude Code with: npm install -g @anthropic-ai/claude-code",
+            file=sys.stderr,
+        )
+        raise SystemExit(127)
+
+    command = [claude_command, *args]
     env = _claude_child_env(settings, os.environ)
     process: subprocess.Popen[bytes] | None = None
     try:
diff --git a/tests/cli/test_entrypoints.py b/tests/cli/test_entrypoints.py
index 2b81c8ad..6b29c0c0 100644
--- a/tests/cli/test_entrypoints.py
+++ b/tests/cli/test_entrypoints.py
@@ -222,6 +222,7 @@ def test_launch_claude_passes_args_and_child_env(
     with (
         patch("cli.entrypoints.get_settings", return_value=settings),
         patch("cli.entrypoints._preflight_proxy", return_value=None),
+        patch("cli.entrypoints.shutil.which", return_value="resolved-claude.cmd"),
         patch("cli.entrypoints.subprocess.Popen") as popen,
         patch("cli.entrypoints.register_pid") as register_pid,
         patch("cli.entrypoints.unregister_pid") as unregister_pid,
@@ -234,7 +235,7 @@ def test_launch_claude_passes_args_and_child_env(
 
     assert exc_info.value.code == 7
     popen.assert_called_once()
-    assert popen.call_args.args[0] == ["claude-test", "--model", "sonnet"]
+    assert popen.call_args.args[0] == ["resolved-claude.cmd", "--model", "sonnet"]
     child_env = popen.call_args.kwargs["env"]
     assert child_env["ANTHROPIC_BASE_URL"] == "http://127.0.0.1:9191"
     assert child_env["ANTHROPIC_AUTH_TOKEN"] == "proxy-token"
@@ -252,6 +253,7 @@ def test_launch_claude_keyboard_interrupt_kills_child_tree() -> None:
     with (
         patch("cli.entrypoints.get_settings", return_value=settings),
         patch("cli.entrypoints._preflight_proxy", return_value=None),
+        patch("cli.entrypoints.shutil.which", return_value="resolved-claude.cmd"),
         patch("cli.entrypoints.subprocess.Popen") as popen,
         patch("cli.entrypoints.register_pid"),
         patch("cli.entrypoints.kill_pid_tree_best_effort") as kill_tree,
@@ -268,6 +270,28 @@ def test_launch_claude_keyboard_interrupt_kills_child_tree() -> None:
     unregister_pid.assert_called_once_with(12345)
 
 
+def test_launch_claude_exits_when_command_cannot_be_resolved(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    from cli.entrypoints import launch_claude
+
+    settings = _launcher_settings(claude_bin="claude-missing")
+    with (
+        patch("cli.entrypoints.get_settings", return_value=settings),
+        patch("cli.entrypoints._preflight_proxy", return_value=None),
+        patch("cli.entrypoints.shutil.which", return_value=None),
+        patch("cli.entrypoints.subprocess.Popen") as popen,
+        pytest.raises(SystemExit) as exc_info,
+    ):
+        launch_claude([])
+
+    assert exc_info.value.code == 127
+    popen.assert_not_called()
+    captured = capsys.readouterr()
+    assert "Could not find Claude Code command: claude-missing" in captured.err
+    assert "npm install -g @anthropic-ai/claude-code" in captured.err
+
+
 def test_launch_claude_unreachable_proxy_exits_with_hint(
     capsys: pytest.CaptureFixture[str],
 ) -> None: