security: harden API server key placeholder handling (#30738)

tests/hermes_cli/test_auth_usable_secret.py

@@ -0,0 +1,13 @@
+"""Tests for placeholder API key detection in hermes_cli.auth."""
+
+from hermes_cli.auth import has_usable_secret
+
+
+def test_has_usable_secret_rejects_documented_placeholder_key() -> None:
+    """Network-exposed API server key must reject static documentation placeholders."""
+    assert not has_usable_secret("your_api_key_here", min_length=8)
+
+
+def test_has_usable_secret_accepts_generated_key() -> None:
+    """Random-looking keys should still be accepted."""
+    assert has_usable_secret("b4d59f7fe8b857d0b367ef0f5710b6a4", min_length=8)