diff --git a/.github/run-eval/resolve_model_config.py b/.github/run-eval/resolve_model_config.py
index c21ecc8888..bfde570044 100755
--- a/.github/run-eval/resolve_model_config.py
+++ b/.github/run-eval/resolve_model_config.py
@@ -132,6 +132,11 @@
         "display_name": "GPT-5.3 Codex",
         "llm_config": {"model": "litellm_proxy/gpt-5-3-codex"},
     },
+    "gpt-5.4-codex": {
+        "id": "gpt-5.4-codex",
+        "display_name": "GPT-5.4 Codex",
+        "llm_config": {"model": "litellm_proxy/gpt-5.4-codex"},
+    },
     "gpt-5.2-high-reasoning": {
         "id": "gpt-5.2-high-reasoning",
         "display_name": "GPT-5.2 High Reasoning",
diff --git a/openhands-sdk/openhands/sdk/llm/utils/model_prompt_spec.py b/openhands-sdk/openhands/sdk/llm/utils/model_prompt_spec.py
index da226703a3..a61185fb0f 100644
--- a/openhands-sdk/openhands/sdk/llm/utils/model_prompt_spec.py
+++ b/openhands-sdk/openhands/sdk/llm/utils/model_prompt_spec.py
@@ -38,7 +38,13 @@ class ModelPromptSpec(BaseModel):
     "openai_gpt": (
         (
             "gpt-5-codex",
-            ("gpt-5-codex", "gpt-5.1-codex", "gpt-5.2-codex", "gpt-5.3-codex"),
+            (
+                "gpt-5-codex",
+                "gpt-5.1-codex",
+                "gpt-5.2-codex",
+                "gpt-5.3-codex",
+                "gpt-5.4-codex",
+            ),
         ),
         ("gpt-5", ("gpt-5", "gpt-5.1", "gpt-5.2")),
     ),
diff --git a/tests/github_workflows/test_resolve_model_config.py b/tests/github_workflows/test_resolve_model_config.py
index 2ed496df68..e1b0ea0228 100644
--- a/tests/github_workflows/test_resolve_model_config.py
+++ b/tests/github_workflows/test_resolve_model_config.py
@@ -491,3 +491,12 @@ def test_models_importable_without_litellm():
         f"stderr: {result.stderr}"
     )
     assert "SUCCESS" in result.stdout
+
+
+def test_gpt_5_4_codex_config():
+    """Test that gpt-5.4-codex has correct configuration."""
+    model = MODELS["gpt-5.4-codex"]
+
+    assert model["id"] == "gpt-5.4-codex"
+    assert model["display_name"] == "GPT-5.4 Codex"
+    assert model["llm_config"]["model"] == "litellm_proxy/gpt-5.4-codex"
diff --git a/tests/sdk/llm/test_model_features.py b/tests/sdk/llm/test_model_features.py
index 9032c8dd39..297683abdb 100644
--- a/tests/sdk/llm/test_model_features.py
+++ b/tests/sdk/llm/test_model_features.py
@@ -39,6 +39,7 @@ def test_model_matches(name, pattern, expected):
         # GPT-5 family
         ("gpt-5.2", True),
         ("gpt-5.2-codex", True),
+        ("gpt-5.4-codex", True),
         ("gpt-4o", False),
         ("claude-3-5-sonnet", False),
         ("gemini-1.5-pro", False),