Upload agent.py

agent.py

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+"""
+HF Agents Course — Unit 4
+GAIA Level 1 Agent (LangGraph + Qwen3.5-35B-A3B)
+"""
+
+import os
+from dotenv import load_dotenv
+from langchain_openai import ChatOpenAI
+from langgraph.graph import StateGraph, END
+from langchain_core.messages import HumanMessage
+from typing import TypedDict, Annotated
+import operator
+
+# =========================
+# 基础配置
+# =========================
+load_dotenv()
+
+AGICTO_API_KEY = os.getenv("AGICTO_API_KEY")
+AGICTO_BASE_URL = os.getenv("AGICTO_BASE_URL", "https://agicto.com/v1")
+
+llm = ChatOpenAI(
+    model="qwen3.5-35b-a3b",
+    openai_api_key=AGICTO_API_KEY,
+    openai_api_base=AGICTO_BASE_URL,
+    temperature=0.1,
+    max_tokens=1024,
+)
+
+# =========================
+# System Prompt（GAIA 专用）
+# =========================
+SYSTEM_PROMPT = (
+    "You are a GAIA benchmark agent.\n"
+    "Think step-by-step internally.\n"
+    "Do NOT explain your reasoning.\n"
+    "Output ONLY the final exact answer.\n"
+    "No units, no punctuation, no extra words.\n"
+    "If the question includes a file URL, use its content."
+)
+
+# =========================
+# LangGraph State
+# =========================
+class AgentState(TypedDict):
+    messages: Annotated[list, operator.add]
+
+def build_graph():
+    def run_agent(state: AgentState) -> AgentState:
+        response = llm.invoke(state["messages"])
+        return {"messages": [response]}
+
+    graph = StateGraph(AgentState)
+    graph.add_node("agent", run_agent)
+    graph.set_entry_point("agent")
+    graph.add_edge("agent", END)
+    return graph.compile()
+
+graph = build_graph()
+
+# =========================
+# ✅ HF 官方接口
+# =========================
+def agent(question: str, files: list[str] | None = None) -> str:
+    """
+    必须保留此函数签名，HF Unit 4 评分器会直接调用。
+    """
+    messages = [
+        {"role": "system", "content": SYSTEM_PROMPT},
+        {"role": "user", "content": question},
+    ]
+
+    result = graph.invoke({"messages": messages})
+    answer = result["messages"][-1].content
+
+    # ✅ GAIA 硬性规则
+    return answer.strip().splitlines()[0]