diff --git a/hermes_cli/config.py b/hermes_cli/config.py
index 772025845da..38e318a36fd 100644
--- a/hermes_cli/config.py
+++ b/hermes_cli/config.py
@@ -2533,10 +2533,32 @@ def validate_config_structure(config: Optional[Dict[str, Any]] = None) -> List["
                         "Add the API endpoint URL, e.g.: base_url: https://api.example.com/v1",
                     ))
 
-    # ── fallback_model must be a top-level dict with provider + model ────
+    # ── fallback_model: single dict OR list of dicts (chain) ─────────────
     fb = config.get("fallback_model")
     if fb is not None:
-        if not isinstance(fb, dict):
+        if isinstance(fb, list):
+            # Chain fallback — validate each entry
+            for i, entry in enumerate(fb):
+                if not isinstance(entry, dict):
+                    issues.append(ConfigIssue(
+                        "error",
+                        f"fallback_model[{i}] should be a dict, got {type(entry).__name__}",
+                        "Each entry needs provider + model",
+                    ))
+                else:
+                    if not entry.get("provider"):
+                        issues.append(ConfigIssue(
+                            "warning",
+                            f"fallback_model[{i}] is missing 'provider' field",
+                            "Add: provider: openrouter (or another provider)",
+                        ))
+                    if not entry.get("model"):
+                        issues.append(ConfigIssue(
+                            "warning",
+                            f"fallback_model[{i}] is missing 'model' field",
+                            "Add: model: <model-name>",
+                        ))
+        elif not isinstance(fb, dict):
             issues.append(ConfigIssue(
                 "error",
                 f"fallback_model should be a dict with 'provider' and 'model', got {type(fb).__name__}",
@@ -3468,7 +3490,12 @@ def save_config(config: Dict[str, Any]):
     if not sec or sec.get("redact_secrets") is None:
         parts.append(_SECURITY_COMMENT)
     fb = normalized.get("fallback_model", {})
-    if not fb or not isinstance(fb, dict) or not (fb.get("provider") and fb.get("model")):
+    fb_is_valid = False
+    if isinstance(fb, list):
+        fb_is_valid = any(isinstance(e, dict) and e.get("provider") and e.get("model") for e in fb)
+    elif isinstance(fb, dict):
+        fb_is_valid = bool(fb.get("provider") and fb.get("model"))
+    if not fb_is_valid:
         parts.append(_FALLBACK_COMMENT)
 
     atomic_yaml_write(
diff --git a/tests/hermes_cli/test_config_validation.py b/tests/hermes_cli/test_config_validation.py
index c18afc9110b..7209e638f9a 100644
--- a/tests/hermes_cli/test_config_validation.py
+++ b/tests/hermes_cli/test_config_validation.py
@@ -136,6 +136,40 @@ class TestFallbackModelValidation:
         fb_issues = [i for i in issues if "fallback" in i.message.lower()]
         assert len(fb_issues) == 0
 
+    def test_valid_fallback_list(self):
+        """List-form fallback_model (chain) should validate when every entry has provider+model."""
+        issues = validate_config_structure({
+            "fallback_model": [
+                {"provider": "openrouter", "model": "anthropic/claude-sonnet-4"},
+                {"provider": "anthropic", "model": "claude-sonnet-4-6"},
+            ],
+        })
+        fb_issues = [i for i in issues if "fallback" in i.message.lower()]
+        assert len(fb_issues) == 0
+
+    def test_fallback_list_entry_missing_provider(self):
+        issues = validate_config_structure({
+            "fallback_model": [
+                {"provider": "openrouter", "model": "anthropic/claude-sonnet-4"},
+                {"model": "claude-sonnet-4-6"},
+            ],
+        })
+        assert any("fallback_model[1]" in i.message and "provider" in i.message for i in issues)
+
+    def test_fallback_list_entry_missing_model(self):
+        issues = validate_config_structure({
+            "fallback_model": [
+                {"provider": "openrouter"},
+            ],
+        })
+        assert any("fallback_model[0]" in i.message and "model" in i.message for i in issues)
+
+    def test_fallback_list_entry_not_a_dict(self):
+        issues = validate_config_structure({
+            "fallback_model": ["openrouter:anthropic/claude-sonnet-4"],
+        })
+        assert any("fallback_model[0]" in i.message and "should be a dict" in i.message for i in issues)
+
 
 class TestMissingModelSection:
     """Warn when custom_providers exists but model section is missing."""