diff --git a/tests/agent/test_external_process_provider_init.py b/tests/agent/test_external_process_provider_init.py
new file mode 100644
index 0000000000..9771c68285
--- /dev/null
+++ b/tests/agent/test_external_process_provider_init.py
@@ -0,0 +1,18 @@
+"""External-process profiles receive their resolved ACP launch details at client construction."""
+
+from types import SimpleNamespace
+
+
+def test_explicit_client_kwargs_injects_command_for_any_external_process_profile(monkeypatch):
+    from agent.agent_init import _explicit_client_kwargs
+    from providers.base import ProviderProfile
+
+    profile = ProviderProfile(name="test-process-provider", auth_type="external_process")
+    monkeypatch.setattr("providers.get_provider_profile", lambda _name: profile)
+    agent = SimpleNamespace(
+        provider="test-process-provider", acp_command="/tmp/test-process", acp_args=["--acp", "--stdio"])
+
+    kwargs = _explicit_client_kwargs(agent, "process-placeholder", "acp://test-process", None)
+
+    assert kwargs["command"] == "/tmp/test-process"
+    assert kwargs["args"] == ["--acp", "--stdio"]