diff --git a/main.py b/main.py index 922a39b..28bc1ff 100644 --- a/main.py +++ b/main.py @@ -6,9 +6,7 @@ from langchain_openai import ChatOpenAI from langchain_core.messages import HumanMessage from langchain.tools import tool from deepagents import create_deep_agent -from deepagents.backends import FilesystemBackend, LocalShellBackend, CompositeBackend -from langgraph.graph import StateGraph, START, END -from langgraph.graph.message import add_messages +from deepagents.backends import CompositeBackend, LocalShellBackend, FilesystemBackend # ---------- LLM ---------- llm = ChatOpenAI( @@ -18,13 +16,13 @@ llm = ChatOpenAI( temperature=0.0, ) -# ---------- Backend for deepagents ---------- +# ---------- Backend ---------- backend = CompositeBackend([ LocalShellBackend(workspace_dir="./workspace"), FilesystemBackend(), ]) -# ---------- State definition ---------- +# ---------- State ---------- class ReflectState(TypedDict): question: str draft: str @@ -33,40 +31,58 @@ class ReflectState(TypedDict): round: int max_rounds: int -# ---------- LangGraph nodes ---------- +# ---------- Nodes ---------- +from langgraph.graph import StateGraph, START, END +from langgraph.graph.message import add_messages + +# Helper to format the prompt for each node +DRAFT_PROMPT = """Write a concise answer (5–10 sentences) to the following question: + +{question} +""" + +REFLECT_PROMPT = """You are a critic. Given the draft answer below, evaluate its completeness, specificity, and absence of filler. Respond with: +1. verdict: either "ok" or "needs_revision" +2. critique: 2–3 bullet points explaining what to improve (if any) + +Draft: +{draft} +""" + +REWRITE_PROMPT = """You are revising the draft answer based on the critique. Produce a new draft that addresses the points. Keep the answer concise (5–10 sentences). + +Critique: +{critique} + +Previous draft: +{draft} +""" + +# Node functions async def draft_answer(state: ReflectState) -> ReflectState: - prompt = f"Write a concise answer (5–10 sentences) to the following question:\n\n{state['question']}" - response = await llm.ainvoke([HumanMessage(content=prompt)]) + response = await llm.ainvoke([HumanMessage(content=DRAFT_PROMPT.format(question=state["question"]))]) state["draft"] = response.content.strip() return state async def reflect(state: ReflectState) -> ReflectState: - prompt = ( - "You are a critic. Evaluate the draft answer for completeness, specificity, and lack of filler.\n" - "Return a verdict ('ok' or 'needs_revision') and 2–3 bullet points of critique.\n" - f"Draft: {state['draft']}" - ) - response = await llm.ainvoke([HumanMessage(content=prompt)]) - # Simple parsing: first line verdict, rest critique - lines = response.content.strip().splitlines() - verdict = lines[0].strip().lower() - critique = "\n".join(lines[1:]).strip() + response = await llm.ainvoke([HumanMessage(content=REFLECT_PROMPT.format(draft=state["draft"]))]) + # Parse verdict and critique + text = response.content.strip() + verdict_line = next((l for l in text.splitlines() if l.lower().startswith("verdict:")), "") + critique_lines = [l for l in text.splitlines() if l.startswith("-") or l.startswith("•")] + verdict = verdict_line.split(":",1)[1].strip().lower() if verdict_line else "needs_revision" + critique = "\n".join(critique_lines) if critique_lines else "" state["verdict"] = verdict state["critique"] = critique return state async def rewrite(state: ReflectState) -> ReflectState: - prompt = ( - "Rewrite the draft answer incorporating the following critique. Keep the answer concise (5–10 sentences).\n" - f"Critique: {state['critique']}\n" - f"Original draft: {state['draft']}" - ) - response = await llm.ainvoke([HumanMessage(content=prompt)]) + response = await llm.ainvoke([HumanMessage(content=REWRITE_PROMPT.format(critique=state["critique"], draft=state["draft"]))]) state["draft"] = response.content.strip() state["round"] += 1 return state -# ---------- Graph construction ---------- +# ---------- Graph ---------- graph = StateGraph(ReflectState) graph.add_node("draft_answer", draft_answer) graph.add_node("reflect", reflect) @@ -76,24 +92,30 @@ graph.add_node("rewrite", rewrite) graph.set_entry_point("draft_answer") # Transitions +# After draft -> reflect graph.add_edge("draft_answer", "reflect") -# From reflect: if ok -> END, else if needs_revision and round < max_rounds -> rewrite -graph.add_conditional_edges( - "reflect", - lambda state: ( - "END" if state["verdict"] == "ok" else ( - "rewrite" if state["round"] < state["max_rounds"] else "END" - ) - ), -) +# After reflect +# if ok -> END +# if needs_revision and round < max_rounds -> rewrite +# else -> END + +def reflect_conditional(state: ReflectState): + if state["verdict"] == "ok": + return "END" + if state["round"] < state["max_rounds"]: + return "rewrite" + return "END" + +graph.add_conditional_edges("reflect", reflect_conditional, {"rewrite": "rewrite", "END": "END"}) +# After rewrite -> reflect graph.add_edge("rewrite", "reflect") -app = graph.compile() +graph.compile() # ---------- DeepAgent wrapper ---------- @tool -def run_graph(question: str, max_rounds: int = 2) -> str: - """Run the reflection graph for a given question.""" +def run_reflect_graph(question: str, max_rounds: int = 2) -> str: + """Run the reflection graph and return the final draft.""" initial_state: ReflectState = { "question": question, "draft": "", @@ -102,20 +124,20 @@ def run_graph(question: str, max_rounds: int = 2) -> str: "round": 0, "max_rounds": max_rounds, } - result = app.invoke(initial_state) + result = graph.invoke(initial_state) return result["draft"] agent = create_deep_agent( model=llm, - tools=[run_graph], + tools=[run_reflect_graph], backend=backend, - system_prompt="You are an assistant that can generate and improve answers using reflection. Use the provided tool to get a refined answer.", + system_prompt="You are an assistant that can answer questions and self‑critique using the provided tool.", ) async def main(): - question = "Объясни студенту разницу между tool и resource в MCP" + question = "Объясни студенту разницу между tool и resource в MCP." response = await agent.ainvoke( - {"messages": [HumanMessage(content=question)]}, + {"messages": [HumanMessage(content=f"Please answer: {question}")]}, {"configurable": {"thread_id": "session-1"}}, ) print("Final answer:\n", response["messages"][-1].content)