fix(moa): preserve legacy preset updates and suppress warnings

hermes_cli/config.py

@@ -904,7 +904,11 @@ def get_missing_config_fields() -> List[Dict[str, Any]]:
             if key not in current:
                 missing.append({"key": full_key, "default": default_value,
                                 "description": f"New config option: {full_key}"})
-            elif isinstance(default_value, dict) and isinstance(current.get(key), dict):
+            elif (
+                isinstance(default_value, dict)
+                and isinstance(current.get(key), dict)
+                and not (prefix == "moa" and key == "presets")
+            ):
                 _check(default_value, current[key], full_key)
 
     _check(DEFAULT_CONFIG, load_config())

hermes_cli/web_routers/models.py

@@ -310,7 +310,8 @@ def set_moa_models(body: MoaConfigPayload, profile: Optional[str] = None):
         # desktop's debounced PUT /api/config autosave races it, so the whole
         # span holds _CONFIG_MUTATION_LOCK or one of the two saves is dropped.
         with config_write_scope(body.profile or profile):
-            if body.presets:
+            legacy_flat_update = not body.presets
+            if not legacy_flat_update:
                 raw = {
                     "default_preset": body.default_preset,
                     "active_preset": body.active_preset,
@@ -339,9 +340,28 @@ def set_moa_models(body: MoaConfigPayload, profile: Optional[str] = None):
                 # MoaConfigPayload; an editor round-trip must not reset it.
                 raw["privacy_filter"] = existing_moa["privacy_filter"]
             normalized = normalize_moa_config(raw)
+            if legacy_flat_update and isinstance(existing_moa, dict):
+                existing_presets = existing_moa.get("presets")
+                existing_default = existing_moa.get("default_preset")
+                if isinstance(existing_presets, dict):
+                    if isinstance(existing_default, str) and existing_default in existing_presets:
+                        # Older clients update the flat default preset; keep the existing
+                        # default name and any valid active selection from the stored map.
+                        synthesized_default = normalized.get("default_preset")
+                        if (
+                            isinstance(synthesized_default, str)
+                            and synthesized_default in normalized["presets"]
+                        ):
+                            normalized["presets"][existing_default] = normalized["presets"].pop(
+                                synthesized_default
+                            )
+                            normalized["default_preset"] = existing_default
+                    existing_active = existing_moa.get("active_preset")
+                    if isinstance(existing_active, str) and existing_active in existing_presets:
+                        normalized["active_preset"] = existing_active
             from hermes_cli import config as config_mod
             updated = config_mod._merge_partial_save(raw_cfg, {"moa": normalized})
-            if body.presets:
+            if not legacy_flat_update:
                 # ``_merge_partial_save`` retains undeclared metadata on surviving presets;
                 # filter after that merge so omitted names are authoritative deletions.
                 merged_presets = updated["moa"]["presets"]

tests/hermes_cli/test_moa_preset_config_warnings.py

@@ -0,0 +1,17 @@
+"""A user's named MoA presets are not schema-defaulted config options."""
+
+from hermes_cli import config as hermes_config
+
+
+def test_missing_config_fields_ignores_user_named_presets_but_checks_schema_options(monkeypatch):
+    """Custom preset names must not be compared against the built-in ``default`` name."""
+    monkeypatch.setattr(
+        hermes_config,
+        "load_config",
+        lambda: {"moa": {"presets": {"keep_a": {}}}, "terminal": {}},
+    )
+
+    missing_keys = {field["key"] for field in hermes_config.get_missing_config_fields()}
+
+    assert not any(key.startswith("moa.presets.") for key in missing_keys)
+    assert "terminal.backend" in missing_keys

tests/hermes_cli/test_moa_preset_deletion.py

@@ -20,6 +20,7 @@ import subprocess
 import sys
 from pathlib import Path
 
+import pytest
 import yaml
 
 from hermes_cli.web_models import MoaConfigPayload, MoaModelSlot, MoaPresetPayload
@@ -216,3 +217,71 @@ def test_deletion_preserves_privacy_filter_and_retained_preset_metadata(tmp_path
     assert on_disk["save_traces"] is True
     assert on_disk["trace_dir"] == "/custom/traces"
     assert on_disk["presets"]["keep_a"]["operator_note"] == "retain me"
+
+
+@pytest.mark.parametrize("include_presets", [False, True], ids=["missing-presets", "empty-presets"])
+def test_legacy_flat_update_preserves_named_presets_and_valid_default(
+    tmp_path, monkeypatch, include_presets
+):
+    """Older flat clients preserve named presets and a valid persisted active selection."""
+    home = tmp_path / ".hermes"
+    home.mkdir()
+    seeded = _three_presets()
+    seeded["active_preset"] = "keep_b"
+    _seed(home, monkeypatch, seeded)
+
+    payload = {
+        "active_preset": "",
+        "reference_models": [MoaModelSlot(provider="openai-codex", model="gpt-5.8")],
+        "aggregator": MoaModelSlot(provider="anthropic", model="claude-opus-5"),
+        "enabled": True,
+    }
+    if include_presets:
+        payload["presets"] = {}
+
+    set_moa_models(MoaConfigPayload(**payload))
+
+    moa = _on_disk(home)["moa"]
+    assert set(moa["presets"]) == {"keep_a", "doomed", "keep_b"}
+    assert moa["default_preset"] == "keep_a"
+    assert moa["active_preset"] == "keep_b"
+    assert moa["active_preset"] in moa["presets"]
+    assert "default" not in moa["presets"]
+    assert moa["presets"]["keep_a"]["reference_models"] == [
+        {"provider": "openai-codex", "model": "gpt-5.8", "enabled": True}
+    ]
+    assert moa["presets"]["keep_a"]["aggregator"] == {
+        "provider": "anthropic", "model": "claude-opus-5"
+    }
+    # Legacy flat fields represent the saved default preset. Runtime resolution uses
+    # default_preset when no preset name is explicitly requested; active_preset is metadata.
+    from hermes_cli.moa_config import resolve_moa_preset
+
+    assert resolve_moa_preset(moa)["reference_models"] == moa["presets"]["keep_a"]["reference_models"]
+    assert moa["presets"]["keep_b"] == seeded["presets"]["keep_b"]
+    assert moa["presets"]["doomed"] == seeded["presets"]["doomed"]
+
+
+def test_legacy_flat_update_with_named_default_and_empty_map_does_not_fail(tmp_path, monkeypatch):
+    """A legacy flat payload's default_preset field cannot rename its synthesized map."""
+    home = tmp_path / ".hermes"
+    home.mkdir()
+    _seed(home, monkeypatch, _three_presets())
+
+    result = set_moa_models(
+        MoaConfigPayload(
+            default_preset="keep_b",
+            presets={},
+            reference_models=[MoaModelSlot(provider="openai-codex", model="gpt-5.8")],
+            aggregator=MoaModelSlot(provider="anthropic", model="claude-opus-5"),
+            enabled=True,
+        )
+    )
+
+    moa = _on_disk(home)["moa"]
+    assert result["ok"] is True
+    assert set(moa["presets"]) == {"keep_a", "doomed", "keep_b"}
+    assert moa["default_preset"] == "keep_a"
+    assert moa["presets"]["keep_a"]["reference_models"] == [
+        {"provider": "openai-codex", "model": "gpt-5.8", "enabled": True}
+    ]