fix: getting context window sizes of models without prefixes (#994)

* fix: getting context window sizes of models without prefixes

* feat: limit split counts to 1

libs/superagent/app/memory/buffer_memory.py

@@ -7,7 +7,23 @@
 from app.memory.message import BaseMessage
 
 DEFAULT_TOKEN_LIMIT_RATIO = 0.75
-DEFAULT_TOKEN_LIMIT = 3000
+DEFAULT_TOKEN_LIMIT = 3072
+
+
+def get_context_window(model: str) -> int:
+    max_input_tokens = model_cost.get(model, {}).get("max_input_tokens")
+
+    # Some models don't have a provider prefix in their name
+    # But they point to the same model
+    # Example: claude-3-haiku-20240307 and anthropic/claude-3-haiku-20240307
+    if not max_input_tokens:
+        model_parts = model.split("/", 1)
+        if len(model_parts) > 1:
+            model_without_prefix = model_parts[1]
+            max_input_tokens = model_cost.get(model_without_prefix, {}).get(
+                "max_input_tokens", DEFAULT_TOKEN_LIMIT
+            )
+    return max_input_tokens
 
 
 class BufferMemory(BaseMemory):
@@ -21,8 +37,9 @@ def __init__(
         self.memory_store = memory_store
         self.tokenizer_fn = tokenizer_fn
         self.model = model
-        context_window = model_cost.get(self.model, {}).get("max_input_tokens")
-        self.context_window = max_tokens or context_window * DEFAULT_TOKEN_LIMIT_RATIO
+        self.context_window = (
+            max_tokens or get_context_window(model=model) * DEFAULT_TOKEN_LIMIT_RATIO
+        )
 
     def add_message(self, message: BaseMessage) -> None:
         self.memory_store.add_message(message)