Refactor custom tool execution utilities

llama_toolchain/agentic_system/execute_with_custom_tools.py

@@ -0,0 +1,96 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from typing import AsyncGenerator, List
+
+from llama_models.llama3.api.datatypes import *  # noqa: F403
+from llama_toolchain.agentic_system.api import *  # noqa: F403
+from llama_toolchain.memory.api import *  # noqa: F403
+from llama_toolchain.safety.api import *  # noqa: F403
+
+from llama_toolchain.agentic_system.api import (
+    AgenticSystemTurnResponseEventType as EventType,
+)
+from llama_toolchain.tools.custom.datatypes import CustomTool
+
+
+class AgentWithCustomToolExecutor:
+    def __init__(
+        self,
+        api: AgenticSystem,
+        agent_id: str,
+        session_id: str,
+        agent_config: AgentConfig,
+        custom_tools: List[CustomTool],
+    ):
+        self.api = api
+        self.agent_id = agent_id
+        self.session_id = session_id
+        self.agent_config = agent_config
+        self.custom_tools = custom_tools
+
+    async def execute_turn(
+        self,
+        messages: List[Message],
+        attachments: Optional[List[Attachment]] = None,
+        max_iters: int = 5,
+        stream: bool = True,
+    ) -> AsyncGenerator:
+        tools_dict = {t.get_name(): t for t in self.custom_tools}
+
+        current_messages = messages.copy()
+        n_iter = 0
+        while n_iter < max_iters:
+            n_iter += 1
+
+            request = AgenticSystemTurnCreateRequest(
+                agent_id=self.agent_id,
+                session_id=self.session_id,
+                messages=current_messages,
+                attachments=attachments,
+                stream=stream,
+            )
+
+            turn = None
+            async for chunk in self.api.create_agentic_system_turn(request):
+                if chunk.event.payload.event_type != EventType.turn_complete.value:
+                    yield chunk
+                else:
+                    turn = chunk.event.payload.turn
+
+            message = turn.output_message
+            if len(message.tool_calls) == 0:
+                yield chunk
+                return
+
+            if message.stop_reason == StopReason.out_of_tokens:
+                yield chunk
+                return
+
+            tool_call = message.tool_calls[0]
+            if tool_call.tool_name not in tools_dict:
+                m = ToolResponseMessage(
+                    call_id=tool_call.call_id,
+                    tool_name=tool_call.tool_name,
+                    content=f"Unknown tool `{tool_call.tool_name}` was called. Try again with something else",
+                )
+                next_message = m
+            else:
+                tool = tools_dict[tool_call.tool_name]
+                result_messages = await execute_custom_tool(tool, message)
+                next_message = result_messages[0]
+
+            yield next_message
+            current_messages = [next_message]
+
+
+async def execute_custom_tool(tool: CustomTool, message: Message) -> List[Message]:
+    result_messages = await tool.run([message])
+    assert (
+        len(result_messages) == 1
+    ), f"Expected single message, got {len(result_messages)}"
+
+    return result_messages