diff --git a/litellm/model_prices_and_context_window_backup.json b/litellm/model_prices_and_context_window_backup.json
index a783960eddd..46a2593c1a1 100644
--- a/litellm/model_prices_and_context_window_backup.json
+++ b/litellm/model_prices_and_context_window_backup.json
@@ -57496,6 +57496,14 @@
                 "model_info": {
                     "supports_reasoning": true
                 }
+            },
+            {
+                "name": "openai-reasoning-family-baseline",
+                "pattern": "^(?!.*search-api)(?:[a-z0-9_.-]+/)*(?:ft:)?(?:o[1-9]\\d*(?![a-z0-9])|gpt-[5-9](?:\\.\\d+)?(?![0-9.])|(?:gpt-\\d+(?:\\.\\d+)?(?:-[a-z0-9]+)*-)?(?:codex|deep-research|chat-latest)(?![a-z0-9]))",
+                "description": "OpenAI reasoning families by id shape, under any provider namespace and with an optional ft: prefix: the o-series (o1, o3-pro, o4-mini), gpt-5 through gpt-9 majors including dotted minors and suffixed variants (gpt-5.5-cyber, gpt-6-astra), and the codex, deep-research and chat-latest lines when standalone or on a gpt base. gpt-5-search-api is excluded because it is a search-only surface. Every model here is a reasoning model, and the Responses API drops the caller's reasoning param for any mapped OpenAI model whose info lacks supports_reasoning, so an id the registry has not named yet keeps its reasoning settings instead of silently losing them. Rules lose to exact entries. Carries no mode and no pricing, so cost stays on the standard unpriced behavior.",
+                "model_info": {
+                    "supports_reasoning": true
+                }
             }
         ]
     },
diff --git a/model_prices_and_context_window.json b/model_prices_and_context_window.json
index a783960eddd..46a2593c1a1 100644
--- a/model_prices_and_context_window.json
+++ b/model_prices_and_context_window.json
@@ -57496,6 +57496,14 @@
                 "model_info": {
                     "supports_reasoning": true
                 }
+            },
+            {
+                "name": "openai-reasoning-family-baseline",
+                "pattern": "^(?!.*search-api)(?:[a-z0-9_.-]+/)*(?:ft:)?(?:o[1-9]\\d*(?![a-z0-9])|gpt-[5-9](?:\\.\\d+)?(?![0-9.])|(?:gpt-\\d+(?:\\.\\d+)?(?:-[a-z0-9]+)*-)?(?:codex|deep-research|chat-latest)(?![a-z0-9]))",
+                "description": "OpenAI reasoning families by id shape, under any provider namespace and with an optional ft: prefix: the o-series (o1, o3-pro, o4-mini), gpt-5 through gpt-9 majors including dotted minors and suffixed variants (gpt-5.5-cyber, gpt-6-astra), and the codex, deep-research and chat-latest lines when standalone or on a gpt base. gpt-5-search-api is excluded because it is a search-only surface. Every model here is a reasoning model, and the Responses API drops the caller's reasoning param for any mapped OpenAI model whose info lacks supports_reasoning, so an id the registry has not named yet keeps its reasoning settings instead of silently losing them. Rules lose to exact entries. Carries no mode and no pricing, so cost stays on the standard unpriced behavior.",
+                "model_info": {
+                    "supports_reasoning": true
+                }
             }
         ]
     },
diff --git a/tests/test_litellm/litellm_core_utils/test_fallback_generalizations.py b/tests/test_litellm/litellm_core_utils/test_fallback_generalizations.py
index b0220a36054..b6e656f282a 100644
--- a/tests/test_litellm/litellm_core_utils/test_fallback_generalizations.py
+++ b/tests/test_litellm/litellm_core_utils/test_fallback_generalizations.py
@@ -677,3 +677,48 @@ def test_deployment_model_info_beats_the_seeded_rule_defaults(shipped_cost_map):
 
     assert litellm.model_cost[model]["supports_reasoning"] is False
     assert litellm.supports_reasoning(model="some-org/NoThink-1", custom_llm_provider="wandb") is False
+
+
+def test_shipped_rules_flag_unmapped_openai_reasoning_families(shipped_cost_map):
+    for model in (
+        "gpt-5.7-nova",
+        "openai/gpt-6",
+        "ft:gpt-5.1-2025-11-13:org::abc",
+        "o5-mini",
+        "gpt-5.6-codex-max",
+        "o4-mini-deep-research-2027-01-01",
+        "gpt-5.7-chat-latest",
+        "azure/gpt-5.7-cyber",
+        "openai/codex-mini-latest-2027",
+    ):
+        assert model not in litellm.model_cost, model
+        assert match_capability_generalizations(model) == {"supports_reasoning": True}, model
+    info = litellm.get_model_info("gpt-5.7-nova", custom_llm_provider="openai")
+    assert info["litellm_provider"] == "openai"
+    assert info["supports_reasoning"] is True
+    assert info.get("mode") is None
+    assert not info.get("input_cost_per_token")
+    assert litellm.supports_reasoning(model="gpt-5.7-nova", custom_llm_provider="openai") is True
+
+
+def test_shipped_openai_reasoning_rule_skips_non_reasoning_gpt_ids(shipped_cost_map):
+    for model in (
+        "gpt-4o",
+        "gpt-4.1-nano-new",
+        "gpt-oss-120b",
+        "gpt-realtime-2027",
+        "gpt-image-2",
+        "gpt-5-search-api-2027-01-01",
+        "omni-moderation-new",
+        "text-embedding-4",
+        "vendor/my-codex-embedding",
+        "some-codex-model",
+        "azure/gpt-35-turbo-0125-custom",
+        "github_copilot/gpt-41-copilot-new",
+    ):
+        assert match_capability_generalizations(model) is None, model
+
+
+def test_shipped_openai_reasoning_rule_loses_to_mapped_entries(shipped_cost_map):
+    assert "gpt-5-search-api" in litellm.model_cost
+    assert litellm.supports_reasoning(model="gpt-5-search-api", custom_llm_provider="openai") is False