feat: add provider data keys for Cerebras, Databricks, NVIDIA, and RunPod (#3734)

# What does this PR do?

add provider-data key passing support to Cerebras, Databricks, NVIDIA
and RunPod

also, added missing tests for Fireworks, Anthropic, Gemini, SambaNova,
and vLLM

addresses #3517 

## Test Plan

ci w/ new tests

---------

Co-authored-by: Ashwin Bharambe <ashwin.bharambe@gmail.com>

src/llama_stack/providers/registry/inference.py

@@ -61,6 +61,7 @@ def available_providers() -> list[ProviderSpec]:
             pip_packages=[],
             module="llama_stack.providers.remote.inference.cerebras",
             config_class="llama_stack.providers.remote.inference.cerebras.CerebrasImplConfig",
+            provider_data_validator="llama_stack.providers.remote.inference.cerebras.config.CerebrasProviderDataValidator",
             description="Cerebras inference provider for running models on Cerebras Cloud platform.",
         ),
         RemoteProviderSpec(
@@ -149,6 +150,7 @@ def available_providers() -> list[ProviderSpec]:
             pip_packages=["databricks-sdk"],
             module="llama_stack.providers.remote.inference.databricks",
             config_class="llama_stack.providers.remote.inference.databricks.DatabricksImplConfig",
+            provider_data_validator="llama_stack.providers.remote.inference.databricks.config.DatabricksProviderDataValidator",
             description="Databricks inference provider for running models on Databricks' unified analytics platform.",
         ),
         RemoteProviderSpec(
@@ -158,6 +160,7 @@ def available_providers() -> list[ProviderSpec]:
             pip_packages=[],
             module="llama_stack.providers.remote.inference.nvidia",
             config_class="llama_stack.providers.remote.inference.nvidia.NVIDIAConfig",
+            provider_data_validator="llama_stack.providers.remote.inference.nvidia.config.NVIDIAProviderDataValidator",
             description="NVIDIA inference provider for accessing NVIDIA NIM models and AI services.",
         ),
         RemoteProviderSpec(
@@ -167,6 +170,7 @@ def available_providers() -> list[ProviderSpec]:
             pip_packages=[],
             module="llama_stack.providers.remote.inference.runpod",
             config_class="llama_stack.providers.remote.inference.runpod.RunpodImplConfig",
+            provider_data_validator="llama_stack.providers.remote.inference.runpod.config.RunpodProviderDataValidator",
             description="RunPod inference provider for running models on RunPod's cloud GPU platform.",
         ),
         RemoteProviderSpec(

src/llama_stack/providers/remote/inference/cerebras/cerebras.py

@@ -18,6 +18,8 @@ from .config import CerebrasImplConfig
 class CerebrasInferenceAdapter(OpenAIMixin):
     config: CerebrasImplConfig
 
+    provider_data_api_key_field: str = "cerebras_api_key"
+
     def get_base_url(self) -> str:
         return urljoin(self.config.base_url, "v1")
 

src/llama_stack/providers/remote/inference/cerebras/config.py

@@ -7,7 +7,7 @@
 import os
 from typing import Any
 
-from pydantic import Field
+from pydantic import BaseModel, Field
 
 from llama_stack.providers.utils.inference.model_registry import RemoteInferenceProviderConfig
 from llama_stack.schema_utils import json_schema_type
@@ -15,6 +15,13 @@ from llama_stack.schema_utils import json_schema_type
 DEFAULT_BASE_URL = "https://api.cerebras.ai"
 
 
+class CerebrasProviderDataValidator(BaseModel):
+    cerebras_api_key: str | None = Field(
+        default=None,
+        description="API key for Cerebras models",
+    )
+
+
 @json_schema_type
 class CerebrasImplConfig(RemoteInferenceProviderConfig):
     base_url: str = Field(

src/llama_stack/providers/remote/inference/databricks/config.py

@@ -6,12 +6,19 @@
 
 from typing import Any
 
-from pydantic import Field, SecretStr
+from pydantic import BaseModel, Field, SecretStr
 
 from llama_stack.providers.utils.inference.model_registry import RemoteInferenceProviderConfig
 from llama_stack.schema_utils import json_schema_type
 
 
+class DatabricksProviderDataValidator(BaseModel):
+    databricks_api_token: str | None = Field(
+        default=None,
+        description="API token for Databricks models",
+    )
+
+
 @json_schema_type
 class DatabricksImplConfig(RemoteInferenceProviderConfig):
     url: str | None = Field(

src/llama_stack/providers/remote/inference/databricks/databricks.py

@@ -20,6 +20,8 @@ logger = get_logger(name=__name__, category="inference::databricks")
 class DatabricksInferenceAdapter(OpenAIMixin):
     config: DatabricksImplConfig
 
+    provider_data_api_key_field: str = "databricks_api_token"
+
     # source: https://docs.databricks.com/aws/en/machine-learning/foundation-model-apis/supported-models
     embedding_model_metadata: dict[str, dict[str, int]] = {
         "databricks-gte-large-en": {"embedding_dimension": 1024, "context_length": 8192},

src/llama_stack/providers/remote/inference/nvidia/config.py

@@ -7,12 +7,19 @@
 import os
 from typing import Any
 
-from pydantic import Field
+from pydantic import BaseModel, Field
 
 from llama_stack.providers.utils.inference.model_registry import RemoteInferenceProviderConfig
 from llama_stack.schema_utils import json_schema_type
 
 
+class NVIDIAProviderDataValidator(BaseModel):
+    nvidia_api_key: str | None = Field(
+        default=None,
+        description="API key for NVIDIA NIM models",
+    )
+
+
 @json_schema_type
 class NVIDIAConfig(RemoteInferenceProviderConfig):
     """

src/llama_stack/providers/remote/inference/nvidia/nvidia.py

@@ -17,6 +17,8 @@ logger = get_logger(name=__name__, category="inference::nvidia")
 class NVIDIAInferenceAdapter(OpenAIMixin):
     config: NVIDIAConfig
 
+    provider_data_api_key_field: str = "nvidia_api_key"
+
     """
     NVIDIA Inference Adapter for Llama Stack.
     """

src/llama_stack/providers/remote/inference/runpod/config.py

@@ -6,12 +6,19 @@
 
 from typing import Any
 
-from pydantic import Field, SecretStr
+from pydantic import BaseModel, Field, SecretStr
 
 from llama_stack.providers.utils.inference.model_registry import RemoteInferenceProviderConfig
 from llama_stack.schema_utils import json_schema_type
 
 
+class RunpodProviderDataValidator(BaseModel):
+    runpod_api_token: str | None = Field(
+        default=None,
+        description="API token for RunPod models",
+    )
+
+
 @json_schema_type
 class RunpodImplConfig(RemoteInferenceProviderConfig):
     url: str | None = Field(

src/llama_stack/providers/remote/inference/runpod/runpod.py

@@ -24,6 +24,7 @@ class RunpodInferenceAdapter(OpenAIMixin):
     """
 
     config: RunpodImplConfig
+    provider_data_api_key_field: str = "runpod_api_token"
 
     def get_base_url(self) -> str:
         """Get base URL for OpenAI client."""