diff --git a/ollama/__init__.py b/ollama/__init__.py
index 92bba280..90b66711 100644
--- a/ollama/__init__.py
+++ b/ollama/__init__.py
@@ -1,4 +1,5 @@
 from ollama._client import AsyncClient, Client
+from importlib.metadata import version, PackageNotFoundError
 from ollama._types import (
   ChatResponse,
   EmbeddingsResponse,
@@ -57,3 +58,10 @@
 ps = _client.ps
 web_search = _client.web_search
 web_fetch = _client.web_fetch
+exists = _client.exists
+
+
+try:
+    __version__ = version("ollama")
+except PackageNotFoundError:
+    __version__ = "unknown"
\ No newline at end of file
diff --git a/ollama/_client.py b/ollama/_client.py
index 8dfce824..3198c9fe 100644
--- a/ollama/_client.py
+++ b/ollama/_client.py
@@ -670,6 +670,12 @@ def ps(self) -> ProcessResponse:
       'GET',
       '/api/ps',
     )
+  def exists(self, model: str) -> bool:
+    try:
+        self.show(model)
+        return True
+    except Exception:
+        return False
 
   def web_search(self, query: str, max_results: int = 3) -> WebSearchResponse:
     """
diff --git a/ollama/_types.py b/ollama/_types.py
index 96529d63..2afb8ee2 100644
--- a/ollama/_types.py
+++ b/ollama/_types.py
@@ -572,7 +572,7 @@ class ShowResponse(SubscriptableBaseModel):
 
   details: Optional[ModelDetails] = None
 
-  modelinfo: Optional[Mapping[str, Any]] = Field(alias='model_info')
+  modelinfo: Optional[Mapping[str, Any]] = Field(default=None, alias='model_info')
 
   parameters: Optional[str] = None
 
diff --git a/tests/test_show.py b/tests/test_show.py
new file mode 100644
index 00000000..8f7433d0
--- /dev/null
+++ b/tests/test_show.py
@@ -0,0 +1,13 @@
+import sys
+sys.path.insert(0, '.')  # force Python to use local folder first
+
+from ollama._types import ShowResponse
+
+test_data = {
+    "template": "test template",
+    "details": None,
+}
+
+response = ShowResponse(**test_data)
+print(f"modelinfo: {response.modelinfo}")
+print("✓ Fix works — no ValidationError")
\ No newline at end of file