diff --git a/src/providers/__init__.py b/src/providers/__init__.py
new file mode 100644
index 000000000..557a3e2b1
--- /dev/null
+++ b/src/providers/__init__.py
@@ -0,0 +1 @@
+"""Inference provider registry package."""
diff --git a/src/providers/inference/__init__.py b/src/providers/inference/__init__.py
new file mode 100644
index 000000000..e4144a405
--- /dev/null
+++ b/src/providers/inference/__init__.py
@@ -0,0 +1 @@
+"""Inference providers, catalog models, and shared registry types."""
diff --git a/src/providers/inference/azure/__init__.py b/src/providers/inference/azure/__init__.py
new file mode 100644
index 000000000..2c404ed6f
--- /dev/null
+++ b/src/providers/inference/azure/__init__.py
@@ -0,0 +1 @@
+"""Azure inference provider package."""
diff --git a/src/providers/inference/bedrock/__init__.py b/src/providers/inference/bedrock/__init__.py
new file mode 100644
index 000000000..0ceafff75
--- /dev/null
+++ b/src/providers/inference/bedrock/__init__.py
@@ -0,0 +1 @@
+"""Bedrock inference provider package."""
diff --git a/src/providers/inference/catalog.py b/src/providers/inference/catalog.py
new file mode 100644
index 000000000..5a7917b16
--- /dev/null
+++ b/src/providers/inference/catalog.py
@@ -0,0 +1,16 @@
+"""Internal inference catalog models."""
+
+from typing import Any
+
+from pydantic import BaseModel, Field
+
+from providers.inference.types import ModelType
+
+
+class CatalogModel(BaseModel):
+    """Cached catalog row for inference providers and the registry."""
+
+    name: str
+    provider_resource_id: str
+    model_type: ModelType
+    metadata: dict[str, Any] = Field(default_factory=dict)
diff --git a/src/providers/inference/openai/__init__.py b/src/providers/inference/openai/__init__.py
new file mode 100644
index 000000000..58e09e810
--- /dev/null
+++ b/src/providers/inference/openai/__init__.py
@@ -0,0 +1 @@
+"""OpenAI inference provider package."""
diff --git a/src/providers/inference/sentence_transformers/__init__.py b/src/providers/inference/sentence_transformers/__init__.py
new file mode 100644
index 000000000..f0803640e
--- /dev/null
+++ b/src/providers/inference/sentence_transformers/__init__.py
@@ -0,0 +1 @@
+"""Sentence-transformers inference provider package."""
diff --git a/src/providers/inference/types.py b/src/providers/inference/types.py
new file mode 100644
index 000000000..e8dbbcc96
--- /dev/null
+++ b/src/providers/inference/types.py
@@ -0,0 +1,19 @@
+"""Shared literals and aliases for the inference provider registry."""
+
+from typing import Any, Final, Literal
+
+ProviderType = Literal[
+    "openai",
+    "azure",
+    "vertexai",
+    "bedrock",
+    "watsonx",
+    "vllm",
+    "sentence_transformers",
+]
+
+ModelType = Literal["llm", "embedding", "rerank"]
+
+type ProviderId = str
+
+PROVIDER_CLASSES: Final[dict[ProviderType, Any]] = {}
diff --git a/src/providers/inference/vertexai/__init__.py b/src/providers/inference/vertexai/__init__.py
new file mode 100644
index 000000000..4039d7de8
--- /dev/null
+++ b/src/providers/inference/vertexai/__init__.py
@@ -0,0 +1 @@
+"""Vertex AI inference provider package."""
diff --git a/src/providers/inference/vllm/__init__.py b/src/providers/inference/vllm/__init__.py
new file mode 100644
index 000000000..debb49eb6
--- /dev/null
+++ b/src/providers/inference/vllm/__init__.py
@@ -0,0 +1 @@
+"""vLLM inference provider package."""
diff --git a/src/providers/inference/watsonx/__init__.py b/src/providers/inference/watsonx/__init__.py
new file mode 100644
index 000000000..3ef1ef4ef
--- /dev/null
+++ b/src/providers/inference/watsonx/__init__.py
@@ -0,0 +1 @@
+"""WatsonX inference provider package."""
diff --git a/tests/unit/providers/__init__.py b/tests/unit/providers/__init__.py
new file mode 100644
index 000000000..5f2ac7b20
--- /dev/null
+++ b/tests/unit/providers/__init__.py
@@ -0,0 +1 @@
+"""Unit tests for the providers package."""
diff --git a/tests/unit/providers/inference/__init__.py b/tests/unit/providers/inference/__init__.py
new file mode 100644
index 000000000..c8331a150
--- /dev/null
+++ b/tests/unit/providers/inference/__init__.py
@@ -0,0 +1 @@
+"""Unit tests for providers.inference."""
diff --git a/tests/unit/providers/inference/test_catalog.py b/tests/unit/providers/inference/test_catalog.py
new file mode 100644
index 000000000..075f52634
--- /dev/null
+++ b/tests/unit/providers/inference/test_catalog.py
@@ -0,0 +1,17 @@
+"""Unit tests for internal inference catalog models."""
+
+from providers.inference.catalog import CatalogModel
+
+
+def test_catalog_model_construction() -> None:
+    """CatalogModel stores name, wire id, type, and metadata."""
+    row = CatalogModel(
+        name="fast-chat",
+        provider_resource_id="gpt-4o-mini",
+        model_type="llm",
+        metadata={"context_window": 128000},
+    )
+    assert row.name == "fast-chat"
+    assert row.provider_resource_id == "gpt-4o-mini"
+    assert row.model_type == "llm"
+    assert row.metadata["context_window"] == 128000