diff --git a/.gitignore b/.gitignore
index 0b188bc..592ebfd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,14 @@ target/
 #  and can be added to the global gitignore or merged into this file.  For a more nuclear
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 #.idea/
+
+# Cache directory for conversation sessions
+.cache/
+
+# Added by cargo
+Cargo.lock
+/target
+
+# Environment
+.env
+.env.*
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..de76095
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "user-content-agent"
+version = "0.0.1"
+edition = "2024"
+
+[dependencies]
+reqwest = { version = "0.12", features = ["json", "rustls-tls", "stream"], default-features = false }
+tokio = { version = "1", features = ["full", "signal"] }
+anyhow = "1.0"
+dotenvy = "0.15"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+futures = "0.3"
+async-stream = "0.3"
+chrono = { version = "0.4", features = ["serde"] }
diff --git a/src/cache.rs b/src/cache.rs
new file mode 100644
index 0000000..1bfe1dd
--- /dev/null
+++ b/src/cache.rs
@@ -0,0 +1,145 @@
+use anyhow::{Result, Context};
+use serde::{Deserialize, Serialize};
+use std::fs;
+use std::path::{Path, PathBuf};
+
+/// 会话数据
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct Session {
+    pub messages: Vec<(String, String)>, // (role, content)
+    pub created_at: String,
+    pub updated_at: String,
+}
+
+impl Session {
+    /// 创建新会话
+    pub fn new() -> Self {
+        let now = chrono::Local::now().to_rfc3339();
+        Self {
+            messages: Vec::new(),
+            created_at: now.clone(),
+            updated_at: now,
+        }
+    }
+    
+    /// 添加消息
+    pub fn add_message(&mut self, role: String, content: String) {
+        self.messages.push((role, content));
+        self.updated_at = chrono::Local::now().to_rfc3339();
+    }
+    
+    /// 获取消息列表
+    pub fn get_messages(&self) -> Vec<(String, String)> {
+        self.messages.clone()
+    }
+}
+
+/// 缓存管理器
+pub struct CacheManager {
+    cache_dir: PathBuf,
+}
+
+impl CacheManager {
+    /// 创建缓存管理器
+    pub fn new() -> Result<Self> {
+        let cache_dir = PathBuf::from(".cache/sessions");
+        
+        // 创建缓存目录
+        if !cache_dir.exists() {
+            fs::create_dir_all(&cache_dir)
+                .context("创建缓存目录失败")?;
+        }
+        
+        Ok(Self { cache_dir })
+    }
+    
+    /// 获取最新的会话文件路径
+    pub fn get_latest_session_path(&self) -> Option<PathBuf> {
+        if !self.cache_dir.exists() {
+            return None;
+        }
+        
+        let mut entries: Vec<_> = fs::read_dir(&self.cache_dir)
+            .ok()?
+            .filter_map(|entry| entry.ok())
+            .filter(|entry| {
+                entry.path().extension()
+                    .map(|ext| ext == "json")
+                    .unwrap_or(false)
+            })
+            .collect();
+        
+        // 按修改时间排序（最新的在前）
+        entries.sort_by_key(|entry| {
+            entry.metadata()
+                .and_then(|m| m.modified())
+                .unwrap_or(std::time::SystemTime::UNIX_EPOCH)
+        });
+        entries.reverse();
+        
+        entries.first().map(|entry| entry.path())
+    }
+    
+    /// 创建新的会话文件路径
+    pub fn create_session_path(&self) -> PathBuf {
+        let timestamp = chrono::Local::now().format("%Y%m%d_%H%M%S");
+        self.cache_dir.join(format!("session_{}.json", timestamp))
+    }
+    
+    /// 保存会话
+    pub fn save_session(&self, session: &Session, path: &Path) -> Result<()> {
+        let json = serde_json::to_string_pretty(session)
+            .context("序列化会话失败")?;
+        
+        fs::write(path, json)
+            .context("保存会话文件失败")?;
+        
+        Ok(())
+    }
+    
+    /// 加载会话
+    pub fn load_session(&self, path: &Path) -> Result<Session> {
+        let json = fs::read_to_string(path)
+            .context("读取会话文件失败")?;
+        
+        let session: Session = serde_json::from_str(&json)
+            .context("解析会话文件失败")?;
+        
+        Ok(session)
+    }
+    
+    /// 获取所有会话文件
+    pub fn list_sessions(&self) -> Result<Vec<(String, PathBuf)>> {
+        if !self.cache_dir.exists() {
+            return Ok(Vec::new());
+        }
+        
+        let mut sessions = Vec::new();
+        
+        for entry in fs::read_dir(&self.cache_dir)? {
+            let entry = entry?;
+            let path = entry.path();
+            
+            if path.extension().map(|ext| ext == "json").unwrap_or(false) {
+                if let Ok(metadata) = entry.metadata() {
+                    if let Ok(modified) = metadata.modified() {
+                        let datetime = chrono::DateTime::<chrono::Local>::from(modified);
+                        sessions.push((datetime.format("%Y-%m-%d %H:%M:%S").to_string(), path));
+                    }
+                }
+            }
+        }
+        
+        // 按时间排序（最新的在前）
+        sessions.sort_by(|a, b| b.0.cmp(&a.0));
+        
+        Ok(sessions)
+    }
+}
+
+// 为Session实现Default trait
+impl Default for Session {
+    fn default() -> Self {
+        Self::new()
+    }
+}
diff --git a/src/chat.rs b/src/chat.rs
new file mode 100644
index 0000000..b353340
--- /dev/null
+++ b/src/chat.rs
@@ -0,0 +1,183 @@
+use anyhow::{Result, Context};
+use futures::Stream;
+use serde::{Deserialize, Serialize};
+use std::pin::Pin;
+
+/// 流式输出块
+#[derive(Debug, Clone)]
+pub enum StreamChunk {
+    Reasoning(String),
+    Content(String),
+    Done,
+}
+
+/// AI对话客户端，支持OpenAI兼容的API
+pub struct ChatClient {
+    api_key: String,
+    api_base: String,
+    default_model: String,
+    client: reqwest::Client,
+}
+
+/// 消息结构
+#[derive(Serialize, Debug, Clone)]
+struct Message {
+    role: String,
+    content: String,
+}
+
+/// 请求结构
+#[derive(Serialize, Debug)]
+struct ChatRequest {
+    model: String,
+    messages: Vec<Message>,
+    stream: bool,
+}
+
+/// 流式响应结构
+#[derive(Deserialize, Debug)]
+struct StreamResponse {
+    choices: Vec<StreamChoice>,
+}
+
+#[derive(Deserialize, Debug)]
+struct StreamChoice {
+    delta: StreamDelta,
+    finish_reason: Option<String>,
+}
+
+#[derive(Deserialize, Debug)]
+struct StreamDelta {
+    content: Option<String>,
+    #[serde(rename = "reasoning_content")]
+    reasoning_content: Option<String>,
+}
+
+impl ChatClient {
+    /// 创建新的对话客户端
+    /// 从环境变量读取配置：
+    /// - OPENAI_API_KEY: API密钥（必需）
+    /// - OPENAI_API_BASE: API地址（可选，默认：https://api.openai.com/v1）
+    /// - OPENAI_MODEL: 默认模型（可选，默认：gpt-3.5-turbo）
+    pub fn new() -> Result<Self> {
+        let api_key = std::env::var("OPENAI_API_KEY")
+            .context("未设置环境变量 OPENAI_API_KEY")?;
+        
+        let api_base = std::env::var("OPENAI_API_BASE")
+            .unwrap_or_else(|_| "https://api.openai.com/v1".to_string());
+        
+        let default_model = std::env::var("OPENAI_MODEL")
+            .unwrap_or_else(|_| "gpt-3.5-turbo".to_string());
+        
+        let client = reqwest::Client::new();
+        
+        Ok(Self {
+            api_key,
+            api_base,
+            default_model,
+            client,
+        })
+    }
+    
+    /// 流式发送消息（带对话历史）
+    /// 使用默认模型
+    pub async fn chat_stream(&self, messages: Vec<(String, String)>) -> Result<Pin<Box<dyn Stream<Item = Result<StreamChunk>> + Send + '_>>> {
+        self.chat_stream_with_model(&self.default_model, messages).await
+    }
+    
+    /// 流式发送消息（带对话历史）
+    /// 指定使用的模型
+    /// messages: Vec<(role, content)>，role可以是"user"或"assistant"
+    pub async fn chat_stream_with_model(&self, model: &str, messages: Vec<(String, String)>) -> Result<Pin<Box<dyn Stream<Item = Result<StreamChunk>> + Send + '_>>> {
+        let request = ChatRequest {
+            model: model.to_string(),
+            messages: messages.into_iter().map(|(role, content)| Message { role, content }).collect(),
+            stream: true,
+        };
+        
+        let url = format!("{}/chat/completions", self.api_base);
+        
+        let response = self.client
+            .post(&url)
+            .header("Authorization", format!("Bearer {}", self.api_key))
+            .header("Content-Type", "application/json")
+            .json(&request)
+            .send()
+            .await?;
+        
+        let status = response.status();
+        if !status.is_success() {
+            let error_text = response.text().await?;
+            anyhow::bail!("API请求失败: {} - {}", status, error_text);
+        }
+        
+        let stream = response.bytes_stream();
+        
+        Ok(Box::pin(async_stream::stream! {
+            use futures::StreamExt;
+            
+            let mut buffer = String::new();
+            
+            for await chunk_result in stream {
+                let chunk = chunk_result?;
+                buffer.push_str(&String::from_utf8_lossy(&chunk));
+                
+                // 处理buffer中的完整行
+                while let Some(pos) = buffer.find("\n") {
+                    let line = buffer[..pos].trim().to_string();
+                    buffer.drain(..pos + 1);
+                    
+                    if line.starts_with("data: ") {
+                        let data = &line[6..];
+                        
+                        if data == "[DONE]" {
+                            yield Ok(StreamChunk::Done);
+                            continue;
+                        }
+                        
+                        match serde_json::from_str::<StreamResponse>(data) {
+                            Ok(response) => {
+                                if let Some(choice) = response.choices.first() {
+                                    if let Some(ref finish_reason) = choice.finish_reason {
+                                        if finish_reason == "stop" {
+                                            yield Ok(StreamChunk::Done);
+                                        }
+                                    } else {
+                                        // 将思维过程拆分成单个字符逐个输出
+                                        if let Some(ref reasoning) = choice.delta.reasoning_content {
+                                            for ch in reasoning.chars() {
+                                                yield Ok(StreamChunk::Reasoning(ch.to_string()));
+                                            }
+                                        }
+                                        // 将回复内容拆分成单个字符逐个输出
+                                        if let Some(ref content) = choice.delta.content {
+                                            for ch in content.chars() {
+                                                yield Ok(StreamChunk::Content(ch.to_string()));
+                                            }
+                                        }
+                                    }
+                                }
+                            }
+                            Err(e) => {
+                                // 忽略解析错误，继续处理下一行
+                                eprintln!("解析警告: {} - 数据: {}", e, data);
+                            }
+                        }
+                    }
+                }
+            }
+        }))
+    }
+    
+    /// 流式发送单条消息（无对话历史，兼容旧接口）
+    /// 使用默认模型
+    pub async fn chat_stream_simple(&self, message: &str) -> Result<Pin<Box<dyn Stream<Item = Result<StreamChunk>> + Send + '_>>> {
+        self.chat_stream(vec![("user".to_string(), message.to_string())]).await
+    }
+}
+
+impl Default for ChatClient {
+    fn default() -> Self {
+        Self::new().expect("创建ChatClient失败")
+    }
+}
diff --git a/src/interactive.rs b/src/interactive.rs
new file mode 100644
index 0000000..d48d551
--- /dev/null
+++ b/src/interactive.rs
@@ -0,0 +1,238 @@
+use crate::cache::{CacheManager, Session};
+use crate::chat::ChatClient;
+use anyhow::Result;
+use futures::StreamExt;
+use std::io::{self, Write};
+use std::sync::{Arc, Mutex};
+use tokio::signal;
+
+/// 交互式对话模式
+pub async fn run_interactive() -> Result<()> {
+    println!("=== 交互式AI对话 ===");
+    println!("输入 'exit' 或 'quit' 退出对话");
+    println!("按 Ctrl+C 也可以安全退出并保存会话\n");
+    
+    // 创建缓存管理器
+    let cache_manager = CacheManager::new()?;
+    
+    // 创建AI对话客户端
+    let client = ChatClient::new()?;
+    
+    // 维护对话历史（使用Arc<Mutex<>>以便在信号处理函数中访问）
+    let session = Arc::new(Mutex::new(Session::new()));
+    let session_path = cache_manager.create_session_path();
+    let mut message_count: u32 = 0;
+    
+    // 检查是否有上次会话
+    if let Some(latest_session_path) = cache_manager.get_latest_session_path() {
+        println!("发现上次的对话会话！");
+        println!("是否要恢复上次的对话？ (y/n)");
+        
+        print!("> ");
+        io::stdout().flush()?;
+        
+        let mut input = String::new();
+        io::stdin().read_line(&mut input)?;
+        
+        if input.trim().eq_ignore_ascii_case("y") || input.trim().eq_ignore_ascii_case("yes") {
+            match cache_manager.load_session(&latest_session_path) {
+                Ok(loaded_session) => {
+                    let mut session_guard = session.lock().unwrap();
+                    *session_guard = loaded_session;
+                    let msg_count = session_guard.messages.len();
+                    println!("✓ 已恢复 {} 条对话消息\n", msg_count);
+                    drop(session_guard); // 释放锁
+                    
+                    // 显示最近的几条消息作为提醒
+                    let session_guard = session.lock().unwrap();
+                    let recent_messages = session_guard.messages.len().saturating_sub(4);
+                    if recent_messages < session_guard.messages.len() {
+                        println!("最近的对话: ");
+                        for (role, content) in &session_guard.messages[recent_messages..] {
+                            let prefix = if role == "user" { "你" } else { "AI" };
+                            let display_content = if content.chars().count() > 50 {
+                                let truncated: String = content.chars().take(50).collect();
+                                format!("{}...", truncated)
+                            } else {
+                                content.replace('\n', " ")
+                            };
+                            println!("  {}: {}", prefix, display_content);
+                        }
+                        println!();
+                    }
+                    drop(session_guard); // 释放锁
+                }
+                Err(e) => {
+                    eprintln!("恢复会话失败: {}", e);
+                    eprintln!("将开始新的对话会话\n");
+                }
+            }
+        } else {
+            println!("将开始新的对话会话\n");
+        }
+    }
+    
+    // 设置Ctrl+C信号处理
+    let session_clone = Arc::clone(&session);
+    let session_path_clone = session_path.clone();
+    let cache_manager_clone = CacheManager::new()?;
+    
+    tokio::spawn(async move {
+        match signal::ctrl_c().await {
+            Ok(()) => {
+                println!("\n\n检测到 Ctrl+C，正在保存会话并退出...");
+                let session_guard = session_clone.lock().unwrap();
+                if !session_guard.messages.is_empty() {
+                    match cache_manager_clone.save_session(&session_guard, &session_path_clone) {
+                        Ok(_) => {
+                            let user_messages = session_guard.messages.iter().filter(|(role, _)| role == "user").count();
+                            let ai_messages = session_guard.messages.iter().filter(|(role, _)| role == "assistant").count();
+                            println!("✓ 会话已保存（共 {} 轮对话）", user_messages);
+                            println!("文件: {:?}", session_path_clone);
+                        }
+                        Err(e) => eprintln!("保存会话失败: {}", e),
+                    }
+                }
+                println!("再见！");
+                std::process::exit(0);
+            }
+            Err(err) => {
+                eprintln!("设置信号处理器失败: {}", err);
+            }
+        }
+    });
+    
+    loop {
+        // 显示提示符
+        print!("\n你: ");
+        io::stdout().flush()?;
+        
+        // 读取用户输入
+        let mut input = String::new();
+        io::stdin().read_line(&mut input)?;
+        
+        // 去除首尾空白
+        let input = input.trim();
+        
+        // 检查是否退出
+        if input.eq_ignore_ascii_case("exit") || input.eq_ignore_ascii_case("quit") {
+            println!("\n对话结束，再见！");
+            break;
+        }
+        
+        // 检查输入是否为空
+        if input.is_empty() {
+            continue;
+        }
+        
+        // 添加用户消息到会话
+        {
+            let mut session_guard = session.lock().unwrap();
+            session_guard.add_message("user".to_string(), input.to_string());
+        }
+        message_count += 1;
+        
+        // 每5条消息自动保存一次
+        if message_count % 5 == 0 {
+            let session_guard = session.lock().unwrap();
+            if let Err(e) = cache_manager.save_session(&session_guard, &session_path) {
+                eprintln!("警告: 自动保存失败: {}", e);
+            }
+        }
+        
+        // 发送消息并获取流式回复
+        let messages = {
+            let session_guard = session.lock().unwrap();
+            session_guard.get_messages()
+        };
+        
+        match client.chat_stream(messages).await {
+            Ok(mut stream) => {
+                let mut is_first_content = true;
+                let mut is_reasoning = true;
+                let mut assistant_response = String::new();
+                
+                print!("\x1b[90mAI思维: ");
+                io::stdout().flush()?;
+                
+                while let Some(chunk_result) = stream.next().await {
+                    match chunk_result {
+                        Ok(crate::chat::StreamChunk::Reasoning(ch)) => {
+                            if is_reasoning {
+                                print!("{}", ch);
+                                io::stdout().flush()?;
+                            }
+                        }
+                        Ok(crate::chat::StreamChunk::Content(ch)) => {
+                            if is_first_content {
+                                // 结束思维过程，切换到回复模式
+                                println!("\x1b[0m");
+                                println!();
+                                print!("AI: ");
+                                io::stdout().flush()?;
+                                is_first_content = false;
+                                is_reasoning = false;
+                            }
+                            print!("{}", ch);
+                            io::stdout().flush()?;
+                            assistant_response.push_str(&ch);
+                        }
+                        Ok(crate::chat::StreamChunk::Done) => {
+                            break;
+                        }
+                        Err(e) => {
+                            eprintln!("\n\x1b[31m错误: {}\x1b[0m", e);
+                            break;
+                        }
+                    }
+                }
+                
+                // 确保输出完成
+                if is_reasoning {
+                    // 如果没有收到内容，说明只有思维过程
+                    println!("\x1b[0m");
+                } else {
+                    println!("\x1b[0m");
+                }
+                
+                // 添加AI回复到会话
+                if !assistant_response.is_empty() {
+                    let mut session_guard = session.lock().unwrap();
+                    session_guard.add_message("assistant".to_string(), assistant_response);
+                }
+                
+                // AI回复完成后立即保存会话
+                {
+                    let session_guard = session.lock().unwrap();
+                    if let Err(e) = cache_manager.save_session(&session_guard, &session_path) {
+                        eprintln!("\n警告: 保存会话失败: {}", e);
+                    }
+                }
+            }
+            Err(e) => {
+                eprintln!("\n\x1b[31m发送消息失败: {}\x1b[0m", e);
+                // 出错时移除最后添加的用户消息
+                let mut session_guard = session.lock().unwrap();
+                session_guard.messages.pop();
+                message_count = message_count.saturating_sub(1);
+            }
+        }
+    }
+    
+    // 退出时保存会话
+    let session_guard = session.lock().unwrap();
+    if !session_guard.messages.is_empty() {
+        println!("\n正在保存对话会话...");
+        match cache_manager.save_session(&session_guard, &session_path) {
+            Ok(_) => println!("✓ 会话已保存到 {:?}", session_path),
+            Err(e) => eprintln!("保存会话失败: {}", e),
+        }
+        
+        // 显示会话统计
+        let user_messages = session_guard.messages.iter().filter(|(role, _)| role == "user").count();
+        let ai_messages = session_guard.messages.iter().filter(|(role, _)| role == "assistant").count();
+        println!("本次对话共 {} 轮（你: {}, AI: {}）", user_messages, user_messages, ai_messages);
+    }
+    
+    Ok(())
+}
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..ec27416
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,34 @@
+mod cache;
+mod chat;
+mod interactive;
+mod test;
+
+use anyhow::Result;
+use std::env;
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    // 加载环境变量
+    dotenvy::dotenv().ok();
+    
+    // 获取命令行参数
+    let args: Vec<String> = env::args().collect();
+    
+    match args.get(1).map(|s| s.as_str()) {
+        Some("test") => {
+            // 运行测试模式
+            test::run_test().await?;
+        }
+        Some("interactive") | None => {
+            // 运行交互式对话模式（默认）
+            interactive::run_interactive().await?;
+        }
+        _ => {
+            println!("用法: {} [test|interactive]", args[0]);
+            println!("  test        - 运行测试模式（单次对话）");
+            println!("  interactive - 运行交互式对话模式（默认）");
+        }
+    }
+    
+    Ok(())
+}
diff --git a/src/test.rs b/src/test.rs
new file mode 100644
index 0000000..ba4e31c
--- /dev/null
+++ b/src/test.rs
@@ -0,0 +1,50 @@
+use crate::chat::ChatClient;
+use anyhow::Result;
+use futures::StreamExt;
+
+/// 测试AI对话功能
+pub async fn run_test() -> Result<()> {
+    println!("=== 测试AI对话功能 ===\n");
+    
+    // 创建AI对话客户端
+    let client = ChatClient::new()?;
+    
+    // 创建消息列表（只包含一条用户消息）
+    let messages = vec![("user".to_string(), "你好！请介绍一下你自己。".to_string())];
+    
+    // 发送消息并获取流式回复
+    let mut stream = client.chat_stream(messages).await?;
+    
+    let mut is_first_content = true;
+    let mut is_reasoning = true;
+    
+    print!("\x1b[90m思维过程: ");
+    
+    while let Some(chunk_result) = stream.next().await {
+        match chunk_result? {
+            crate::chat::StreamChunk::Reasoning(text) => {
+                if is_reasoning {
+                    print!("{}", text);
+                }
+            }
+            crate::chat::StreamChunk::Content(text) => {
+                if is_first_content {
+                    println!("\x1b[0m");
+                    println!();
+                    print!("AI回复: ");
+                    is_first_content = false;
+                    is_reasoning = false;
+                }
+                print!("{}", text);
+            }
+            crate::chat::StreamChunk::Done => {
+                break;
+            }
+        }
+    }
+    
+    println!();
+    println!("\n=== 测试完成 ===");
+    
+    Ok(())
+}