最小可用的 Agent 内核仅仅需要：一个 while 循环 + 一个工具。
说白了就是Agent 最本质的“大脑-手脚”循环
Java实现代码
public class AgentLoop {
// 模拟 Anthropic API 客户端
private static final String API_KEY = System.getenv("ANTHROPIC_API_KEY");
private static final String MODEL_ID = System.getenv("MODEL_ID");
private static final HttpClient client = HttpClient.newHttpClient();
// 核心循环
public static void agentLoop(List<Map<String, Object>> messages) {
while (true) {
// 1. 调用 LLM
System.out.println(">>> 正在思考...");
Map<String, Object> response = callLLM(messages);
// 2. 将助手回复加入历史
messages.add(response);
// 3. 检查停止原因
// 注意：这里简化了逻辑，实际需解析 JSON 中的 stop_reason
String stopReason = (String) response.get("stop_reason");
if (!"tool_use".equals(stopReason)) {
return; // 任务完成，退出循环
}
// 4. 执行工具
List<Map<String, Object>> toolResults = new ArrayList<>();
List<Map<String, Object>> content = (List<Map<String, Object>>) response.get("content");
for (Map<String, Object> block : content) {
if ("tool_use".equals(block.get("type"))) {
Map<String, Object> input = (Map<String, Object>) block.get("input");
String command = (String) input.get("command");
String toolId = (String) block.get("id");
System.out.println("\033[33m$ " + command + "\033[0m"); // 黄色输出命令
// 执行 Bash
String output = runBash(command);
System.out.println(output.length() > 200 ? output.substring(0, 200) + "..." : output);
// 构造工具结果
Map<String, Object> result = new HashMap<>();
result.put("type", "tool_result");
result.put("tool_use_id", toolId);
result.put("content", output);
toolResults.add(result);
}
}
// 5. 将工具结果作为用户输入再次加入历史
Map<String, Object> userTurn = new HashMap<>();
userTurn.put("role", "user");
userTurn.put("content", toolResults);
messages.add(userTurn);
}
}
// 模拟 LLM 调用 (实际需替换为 SDK 调用)
private static Map<String, Object> callLLM(List<Map<String, Object>> messages) {
// 这里是一个占位符，实际应发送 HTTP 请求给 Anthropic API
// 返回结构需匹配 API 响应
return new HashMap<>();
}
// 执行 Shell 命令
private static String runBash(String command) {
// 安全检查
if (command.contains("rm -rf /") || command.contains("sudo")) {
return "Error: Dangerous command blocked";
}
try {
ProcessBuilder pb = new ProcessBuilder("bash", "-c", command);
pb.redirectErrorStream(true);
Process p = pb.start();
// 读取输出
BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
StringBuilder output = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
output.append(line).append("\n");
}
// 等待完成 (带超时)
if (!p.waitFor(120, TimeUnit.SECONDS)) {
p.destroyForcibly();
return "Error: Timeout (120s)";
}
String result = output.toString().trim();
return result.isEmpty() ? "(no output)" : result.substring(0, Math.min(result.length(), 50000));
} catch (IOException | InterruptedException e) {
return "Error: " + e.getMessage();
}
}
public static void main(String[] args) {
List<Map<String, Object>> history = new ArrayList<>();
Scanner scanner = new Scanner(System.in);
System.out.println("Agent 已启动 (输入 'q' 退出)");
while (true) {
System.out.print("\033[36ms01 >> \033[0m");
String query = scanner.nextLine();
if (query.trim().equalsIgnoreCase("q") || query.isEmpty()) {
break;
}
Map<String, Object> userMsg = new HashMap<>();
userMsg.put("role", "user");
userMsg.put("content", query);
history.add(userMsg);
agentLoop(history);
// 打印最终回复
System.out.println("Agent 执行完毕。");
}
}
}