fix: add default model gpt4.1 (#5897)

add default model gpt4.1

Co-authored-by: Ari Webb <ari@letta.com>

letta/constants.py

@@ -439,3 +439,6 @@ WEB_SEARCH_MODEL_ENV_VAR_DEFAULT_VALUE = "gpt-4.1-mini-2025-04-14"
 EXCLUDE_MODEL_KEYWORDS_FROM_BASE_TOOL_RULES = ["claude-4-sonnet", "claude-3-5-sonnet", "gpt-5", "gemini-2.5-pro"]
 # But include models with these keywords in base tool rules (overrides exclusion)
 INCLUDE_MODEL_KEYWORDS_BASE_TOOL_RULES = ["mini"]
+
+# Default handle for model used to generate tools
+DEFAULT_GENERATE_TOOL_MODEL_HANDLE = "openai/gpt-4.1"

letta/server/rest_api/routers/v1/tools.py

@@ -7,6 +7,7 @@ from httpx import ConnectError, HTTPStatusError
 from pydantic import BaseModel, Field
 from starlette.responses import StreamingResponse
 
+from letta.constants import DEFAULT_GENERATE_TOOL_MODEL_HANDLE
 from letta.errors import (
     LettaInvalidArgumentError,
     LettaInvalidMCPSchemaError,
@@ -817,7 +818,7 @@ async def generate_tool_from_prompt(
     Generate a tool from the given user prompt.
     """
     actor = await server.user_manager.get_actor_or_default_async(actor_id=headers.actor_id)
-    llm_config = await server.get_cached_llm_config_async(actor=actor, handle=request.handle or "anthropic/claude-3-5-sonnet-20240620")
+    llm_config = await server.get_cached_llm_config_async(actor=actor, handle=request.handle or DEFAULT_GENERATE_TOOL_MODEL_HANDLE)
     formatted_prompt = (
         f"Generate a python function named {request.tool_name} using the instructions below "
         + (f"based on this starter code: \n\n```\n{request.starter_code}\n```\n\n" if request.starter_code else "\n")