diff --git a/hermes_cli/models.py b/hermes_cli/models.py
index b939780b4e..9fd45c69ca 100644
--- a/hermes_cli/models.py
+++ b/hermes_cli/models.py
@@ -3325,6 +3325,30 @@ _AGGREGATOR_PROVIDERS = frozenset(
     {"nous", "openrouter", "ai-gateway", "copilot", "kilocode"}
 )
 
+# OpenRouter request-time routing variants (docs: guides/routing/model-variants).
+# These suffixes are per-request routing modifiers valid on ANY model id —
+# ":nitro" sorts the endpoint pool by throughput and admits priority-tier
+# endpoints, ":floor" sorts by price and admits flex-tier endpoints, ":exacto"
+# applies quality-first provider sorting, ":online" attaches the web plugin.
+# They are never separate catalog entries: /models lists only the base id.
+# NOT in this set: ":free", ":batch", ":thinking", ":extended" — those ARE
+# distinct catalog SKUs that appear in /models when they exist, so absence
+# from the listing is authoritative for them and the direct-membership check
+# above handles the valid ones.
+_OPENROUTER_VARIANT_SUFFIXES = frozenset({"nitro", "floor", "exacto", "online"})
+
+
+def _openrouter_variant_base(model_id: str) -> Optional[str]:
+    """Return the base model id when ``model_id`` carries a recognized
+    OpenRouter routing-variant suffix (e.g. ``x-ai/grok-4:nitro`` →
+    ``x-ai/grok-4``), else ``None``."""
+    base, sep, suffix = (model_id or "").rpartition(":")
+    if not sep or not base:
+        return None
+    if suffix.lower() in _OPENROUTER_VARIANT_SUFFIXES:
+        return base
+    return None
+
 # Subscription/OAuth providers whose catalogs RE-EXPOSE other vendors' models
 # would be listed here (tried only as a last resort for bare short-alias
 # resolution, after every native-vendor catalog, so they never hijack an alias
@@ -6812,6 +6836,24 @@ def validate_requested_model(
                 "recognized": True,
                 "message": None,
             }
+        # OpenRouter routing variants (":nitro", ":floor", ...) are request-time
+        # modifiers, not catalog entries — /models lists only the base id.
+        # Validate the BASE against the listing but preserve the suffixed id,
+        # and do this BEFORE fuzzy auto-correction: get_close_matches would
+        # otherwise "correct" `model:nitro` → `model` and silently strip the
+        # user's routing opt-in.
+        _variant_base = (
+            _openrouter_variant_base(requested_for_lookup)
+            if normalized == "openrouter"
+            else None
+        )
+        if _variant_base is not None and _variant_base in set(api_models):
+            return {
+                "accepted": True,
+                "persist": True,
+                "recognized": True,
+                "message": None,
+            }
         else:
             # API responded but model is not listed.  Accept anyway —
             # the user may have access to models not shown in the public
@@ -6853,7 +6895,8 @@ def validate_requested_model(
 
                 _openai_listing_is_authoritative = is_official_openai_host(base_url)
             if not _openai_listing_is_authoritative and _model_in_provider_catalog(
-                requested_for_lookup.lower(), _provider_keys(normalized)
+                (_variant_base or requested_for_lookup).lower(),
+                _provider_keys(normalized),
             ):
                 return {
                     "accepted": True,
@@ -6936,6 +6979,21 @@ def validate_requested_model(
                 "recognized": True,
                 "message": None,
             }
+        # OpenRouter routing-variant suffixes: validate the base id against
+        # the catalog, keep the suffixed id (same rule as the live-listing
+        # path above — variants never appear as catalog entries).
+        if normalized == "openrouter":
+            _cat_variant_base = _openrouter_variant_base(requested_for_lookup)
+            if (
+                _cat_variant_base is not None
+                and _cat_variant_base.lower() in catalog_lower
+            ):
+                return {
+                    "accepted": True,
+                    "persist": True,
+                    "recognized": True,
+                    "message": None,
+                }
         catalog_lower_list = list(catalog_lower.keys())
         auto = get_close_matches(
             requested_for_lookup.lower(), catalog_lower_list, n=1, cutoff=0.9
diff --git a/tests/hermes_cli/test_model_validation.py b/tests/hermes_cli/test_model_validation.py
index 966eae73e7..51387a0bf0 100644
--- a/tests/hermes_cli/test_model_validation.py
+++ b/tests/hermes_cli/test_model_validation.py
@@ -594,3 +594,84 @@ class TestProbeApiModelsUserAgent:
         assert req.get_header("Authorization") is None
 
 
+
+
+# -- validate — OpenRouter routing-variant suffixes (:nitro / :floor / ...) ----
+
+class TestValidateOpenRouterVariantSuffixes:
+    """OpenRouter's `:nitro`, `:floor`, `:exacto`, `:online` are request-time
+    routing modifiers, not catalog models — /models lists only the base id.
+    Validation must accept `base:variant` when `base` is listed, preserve the
+    suffixed id (no auto-correct stripping the routing opt-in), and still
+    reject variants on unknown bases and unknown suffixes."""
+
+    _LISTING = [
+        "~x-ai/grok-latest",
+        "x-ai/grok-4.6",
+        "deepseek/deepseek-v4-flash",
+        "thinkingmachines/inkling:free",
+    ]
+
+    def _validate(self, model):
+        return _validate(model, "openrouter", api_models=self._LISTING)
+
+    @pytest.mark.parametrize("suffix", ["nitro", "floor", "exacto", "online"])
+    def test_variant_on_listed_base_accepted_unmodified(self, suffix):
+        result = self._validate(f"~x-ai/grok-latest:{suffix}")
+        assert result["accepted"] is True
+        assert result["recognized"] is True
+        assert result.get("corrected_model") is None
+        assert result["message"] is None
+
+    def test_variant_not_fuzzy_corrected_to_base(self):
+        """The old failure mode: get_close_matches would 'fix' model:nitro
+        to the bare base id and silently drop the routing behavior."""
+        result = self._validate("x-ai/grok-4.6:nitro")
+        assert result["accepted"] is True
+        assert result.get("corrected_model") is None
+
+    def test_variant_on_unknown_base_rejected(self):
+        result = self._validate("x-ai/notreal-model:nitro")
+        assert result["accepted"] is False
+
+    def test_unknown_suffix_keeps_old_behavior(self):
+        result = self._validate("x-ai/grok-4.6:bogus")
+        assert result["accepted"] is False
+
+    def test_free_sku_still_direct_matched(self):
+        """`:free` SKUs ARE catalog entries; direct membership handles them."""
+        result = self._validate("thinkingmachines/inkling:free")
+        assert result["accepted"] is True
+        assert result.get("corrected_model") is None
+
+    def test_variant_uppercase_suffix_accepted(self):
+        result = self._validate("x-ai/grok-4.6:NITRO")
+        assert result["accepted"] is True
+        assert result.get("corrected_model") is None
+
+    def test_non_openrouter_provider_unaffected(self):
+        """The variant carve-out is OpenRouter-only; other providers keep
+        their existing behavior for colon-suffixed names."""
+        result = _validate(
+            "x-ai/grok-4.6:nitro",
+            "groq",
+            api_models=["x-ai/grok-4.6"],
+        )
+        assert result.get("corrected_model") != "x-ai/grok-4.6:nitro"
+
+    def test_static_catalog_fallback_accepts_variant(self):
+        """Gateway path: /models unreachable → static catalog validates the
+        base id and preserves the suffix."""
+        with patch("hermes_cli.models.fetch_api_models", return_value=None), \
+             patch(
+                 "hermes_cli.models.provider_model_ids",
+                 return_value=["x-ai/grok-4.6", "anthropic/claude-opus-4.6"],
+             ):
+            result = validate_requested_model(
+                "x-ai/grok-4.6:floor",
+                "openrouter",
+                base_url="https://openrouter.ai/api/v1",
+            )
+        assert result["accepted"] is True
+        assert result["recognized"] is True
+        assert result.get("corrected_model") is None