feat: support agent reflection at local

Author: yaozheng-fang

veadk/reflector/__init__.py

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+# Copyright (c) 2025 Beijing Volcano Engine Technology Co., Ltd. and/or its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

veadk/reflector/base_reflector.py

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+# Copyright (c) 2025 Beijing Volcano Engine Technology Co., Ltd. and/or its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from abc import ABC, abstractmethod
+
+from pydantic import BaseModel
+
+from veadk import Agent
+
+
+class ReflectorResult(BaseModel):
+    optimized_prompt: str
+    """Optimized system prompt"""
+
+    reason: str
+    """Reason for the optimized prompt"""
+
+
+class BaseReflector(ABC):
+    def __init__(self, agent: Agent):
+        self.agent = agent
+
+    @abstractmethod
+    def reflect(self, traces: list[dict]) -> ReflectorResult:
+        """Do agent self-reflection and generate a optimized system prompt.
+
+        Args:
+            traces (list[dict]): The traces for agent reflection.
+
+        Returns:
+            str: The optimized system prompt.
+        """
+        ...

veadk/reflector/local_reflector.py

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+# Copyright (c) 2025 Beijing Volcano Engine Technology Co., Ltd. and/or its affiliates.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import json
+import os
+
+from typing_extensions import override
+
+from veadk import Agent, Runner
+from veadk.reflector.base_reflector import BaseReflector, ReflectorResult
+
+
+class LocalReflector(BaseReflector):
+    def __init__(self, agent: Agent):
+        super().__init__(agent)
+
+    def _read_traces_from_dir(self, trace_dir: str) -> list[dict]:
+        traces = []
+        for file in os.listdir(trace_dir):
+            if file.endswith(".json"):
+                with open(os.path.join(trace_dir, file), "r") as f:
+                    traces.append(json.load(f))
+        return traces
+
+    @override
+    async def reflect(self, trace_file: str) -> ReflectorResult:
+        assert os.path.isfile(trace_file), f"{trace_file} is not a file."
+        assert trace_file.endswith(".json"), f"{trace_file} is not a valid json file."
+
+        with open(trace_file, "r") as f:
+            traces = json.load(f)
+
+        agent = Agent(
+            name="agent_reflector",
+            description="Reflect the traces and generate a optimized system prompt.",
+            instruction="""You are a helpful optimizer and reflector.
+            
+Your task is to reflect the traces and generate a optimized system prompt (based on the given agent's system prompt).
+
+You should response in json format with two fields: 
+- optimized_prompt: The optimized system prompt.
+- reason: The reason for the optimized prompt.
+            """,
+            output_schema=ReflectorResult,
+        )
+        runner = Runner(agent)
+
+        response = await runner.run(
+            messages=f"The system prompt is: {self.agent.instruction}, and the history traces are: {traces}"
+        )
+
+        if response:
+            try:
+                optimized_prompt = json.loads(response).get("optimized_prompt", "")
+                reason = json.loads(response).get("reason", "")
+            except Exception as e:
+                optimized_prompt = ""
+                reason = f"response from optimizer is not valid json: {e}, response: {response}"
+        else:
+            optimized_prompt = ""
+            reason = "response from optimizer is empty"
+
+        return ReflectorResult(
+            optimized_prompt=optimized_prompt,
+            reason=reason,
+        )