diff --git a/docs/my-website/docs/providers/anthropic.md b/docs/my-website/docs/providers/anthropic.md
index 617476b97..198a6a03d 100644
--- a/docs/my-website/docs/providers/anthropic.md
+++ b/docs/my-website/docs/providers/anthropic.md
@@ -4,7 +4,6 @@ LiteLLM supports
 - `claude-3` (`claude-3-opus-20240229`, `claude-3-sonnet-20240229`)
 - `claude-2`
 - `claude-2.1`
-- `claude-instant-1`
 - `claude-instant-1.2`
 
 ## API Keys
@@ -56,7 +55,6 @@ for chunk in response:
 | claude-3-sonnet  | `completion('claude-3-sonnet-20240229', messages)` | `os.environ['ANTHROPIC_API_KEY']`       |
 | claude-2.1  | `completion('claude-2.1', messages)` | `os.environ['ANTHROPIC_API_KEY']`       |
 | claude-2  | `completion('claude-2', messages)` | `os.environ['ANTHROPIC_API_KEY']`       |
-| claude-instant-1  | `completion('claude-instant-1', messages)` | `os.environ['ANTHROPIC_API_KEY']`       |
 | claude-instant-1.2  | `completion('claude-instant-1.2', messages)` | `os.environ['ANTHROPIC_API_KEY']`       |
 
 ## Advanced
diff --git a/litellm/llms/anthropic.py b/litellm/llms/anthropic.py
index 829a8becd..79b84c4d2 100644
--- a/litellm/llms/anthropic.py
+++ b/litellm/llms/anthropic.py
@@ -121,11 +121,29 @@ def completion(
         prompt = prompt_factory(
             model=model, messages=messages, custom_llm_provider="anthropic"
         )
-
+    """
+    format messages for anthropic
+    1. Anthropic supports roles like "user" and "assistant", (here litellm translates system-> assistant)
+    2. The first message always needs to be of role "user"
+    """
+    # 1. Anthropic only supports roles like "user" and "assistant"
     for message in messages:
         if message["role"] == "system":
             message["role"] = "assistant"
 
+    # 2. The first message always needs to be of role "user"
+    if len(messages) > 0:
+        if messages[0]["role"] != "user":
+            # find the index of the first user message
+            for i, message in enumerate(messages):
+                if message["role"] == "user":
+                    break
+
+            # remove the user message at existing position and add it to the front
+            messages.pop(i)
+            # move the first user message to the front
+            messages = [message] + messages
+
     ## Load Config
     config = litellm.AnthropicConfig.get_config()
     for k, v in config.items():
diff --git a/litellm/tests/test_completion.py b/litellm/tests/test_completion.py
index 163a66af3..bbe1dae3a 100644
--- a/litellm/tests/test_completion.py
+++ b/litellm/tests/test_completion.py
@@ -56,7 +56,7 @@ def test_completion_custom_provider_model_name():
 def test_completion_claude():
     litellm.set_verbose = True
     litellm.cache = None
-    litellm.AnthropicConfig(max_tokens_to_sample=200, metadata={"user_id": "1224"})
+    litellm.AnthropicConfig(max_tokens=200, metadata={"user_id": "1224"})
     messages = [
         {
             "role": "system",
@@ -67,7 +67,7 @@ def test_completion_claude():
     try:
         # test without max tokens
         response = completion(
-            model="claude-instant-1",
+            model="claude-instant-1.2",
             messages=messages,
             request_timeout=10,
         )