diff --git a/langchain/VERSION b/langchain/VERSION
index 32786aa437b..44517d5188e 100644
--- a/langchain/VERSION
+++ b/langchain/VERSION
@@ -1 +1 @@
-0.0.18
+0.0.19
diff --git a/langchain/model_laboratory.py b/langchain/model_laboratory.py
index 2bf30904878..614bba344f9 100644
--- a/langchain/model_laboratory.py
+++ b/langchain/model_laboratory.py
@@ -1,6 +1,7 @@
 """Experiment with different models."""
-from typing import List, Optional, Sequence
+from typing import List, Optional, Sequence, Union
 
+from langchain.agents.agent import Agent
 from langchain.chains.base import Chain
 from langchain.chains.llm import LLMChain
 from langchain.input import get_color_mapping, print_text
@@ -11,29 +12,32 @@ from langchain.prompts.prompt import PromptTemplate
 class ModelLaboratory:
     """Experiment with different models."""
 
-    def __init__(self, chains: Sequence[Chain], names: Optional[List[str]] = None):
+    def __init__(
+        self, chains: Sequence[Union[Chain, Agent]], names: Optional[List[str]] = None
+    ):
         """Initialize with chains to experiment with.
 
         Args:
             chains: list of chains to experiment with.
         """
-        if not isinstance(chains[0], Chain):
-            raise ValueError(
-                "ModelLaboratory should now be initialized with Chains. "
-                "If you want to initialize with LLMs, use the `from_llms` method "
-                "instead (`ModelLaboratory.from_llms(...)`)"
-            )
         for chain in chains:
-            if len(chain.input_keys) != 1:
+            if not isinstance(chain, (Chain, Agent)):
                 raise ValueError(
-                    "Currently only support chains with one input variable, "
-                    f"got {chain.input_keys}"
-                )
-            if len(chain.output_keys) != 1:
-                raise ValueError(
-                    "Currently only support chains with one output variable, "
-                    f"got {chain.output_keys}"
+                    "ModelLaboratory should now be initialized with Chains or Agents. "
+                    "If you want to initialize with LLMs, use the `from_llms` method "
+                    "instead (`ModelLaboratory.from_llms(...)`)"
                 )
+            if isinstance(chain, Chain):
+                if len(chain.input_keys) != 1:
+                    raise ValueError(
+                        "Currently only support chains with one input variable, "
+                        f"got {chain.input_keys}"
+                    )
+                if len(chain.output_keys) != 1:
+                    raise ValueError(
+                        "Currently only support chains with one output variable, "
+                        f"got {chain.output_keys}"
+                    )
         if names is not None:
             if len(names) != len(chains):
                 raise ValueError("Length of chains does not match length of names.")