diff --git a/src/cai/sdk/agents/models/openai_chatcompletions.py b/src/cai/sdk/agents/models/openai_chatcompletions.py
index 6324fd6e..48d15683 100644
--- a/src/cai/sdk/agents/models/openai_chatcompletions.py
+++ b/src/cai/sdk/agents/models/openai_chatcompletions.py
@@ -3668,16 +3668,27 @@ class OpenAIChatCompletionsModel(Model):
         # round-robin through them to stay under 40 req/min per key.
         # Only applies when no explicit api_base was routed above (alias,
         # ollama_cloud, or a custom provider fallback): those must keep
-        # their own endpoint + key.
+        # their own endpoint + key. Also only applies to known NIM models.
+        def _is_nim_model(model: str) -> bool:
+            """Check if model is a known NIM model (provider is on NVIDIA NIM)."""
+            provider = model.split("/")[0].lower() if "/" in model else model.lower()
+            nim_providers = {
+                "nvidia", "meta", "google", "microsoft", "mistralai",
+                "llama", "nemotron", "codellama", "mixtral", "phi",
+                "qwen", "yi", "deepseek", "gemma", "stable-diffusion",
+                "sdxl", "cosxl", "proteus", "realistic-vision",
+            }
+            return provider in nim_providers
+
         if is_nim_rotation_configured() and not kwargs.get("api_base"):
-            kwargs["api_key"] = get_next_nim_key()
-            kwargs["custom_llm_provider"] = "openai"
-            kwargs["api_base"] = (
-                resolve_llm_openai_compatible_base(
-                    str(kwargs.get("model") or os.getenv("CAI_MODEL") or "")
-                ).rstrip("/")
-                or os.getenv("OPENAI_API_BASE", "").rstrip("/")
-            )
+            model_str = str(kwargs.get("model") or os.getenv("CAI_MODEL") or "")
+            if _is_nim_model(model_str):
+                kwargs["api_key"] = get_next_nim_key()
+                kwargs["custom_llm_provider"] = "openai"
+                kwargs["api_base"] = (
+                    resolve_llm_openai_compatible_base(model_str).rstrip("/")
+                    or os.getenv("OPENAI_API_BASE", "").rstrip("/")
+                )
 
         # Filter out NotGiven values to avoid JSON serialization issues
         filtered_kwargs = {}
@@ -3785,7 +3796,21 @@ class OpenAIChatCompletionsModel(Model):
                 request_body = {k: v for k, v in request_body.items() if v is not None}
 
                 api_url = f"{openai_api_base.rstrip('/')}/chat/completions"
-                if "api.nvidia.com" in openai_api_base.lower() and is_nim_rotation_configured():
+                model_str = str(kwargs.get("model") or os.getenv("CAI_MODEL") or "")
+                def _is_nim_model(model: str) -> bool:
+                    provider = model.split("/")[0].lower() if "/" in model else model.lower()
+                    nim_providers = {
+                        "nvidia", "meta", "google", "microsoft", "mistralai",
+                        "llama", "nemotron", "codellama", "mixtral", "phi",
+                        "qwen", "yi", "deepseek", "gemma", "stable-diffusion",
+                        "sdxl", "cosxl", "proteus", "realistic-vision",
+                    }
+                    return provider in nim_providers
+                if (
+                    "api.nvidia.com" in openai_api_base.lower()
+                    and is_nim_rotation_configured()
+                    and _is_nim_model(model_str)
+                ):
                     direct_api_key = get_next_nim_key() or "sk-placeholder"
                 else:
                     direct_api_key = (