diff --git a/README-en.md b/README-en.md
index 3934aa1..9d4abb9 100644
--- a/README-en.md
+++ b/README-en.md
@@ -5,103 +5,156 @@
 [![Documentation Status](https://img.shields.io/badge/docs-github_pages-blue.svg)](https://cubenlp.github.io/askchat/)
 [![Coverage](https://codecov.io/gh/cubenlp/askchat/branch/main/graph/badge.svg)](https://codecov.io/gh/cubenlp/askchat)
 
-[English](README-en.md) | [Simplified Chinese](README.md)
+[English](README-en.md) | [简体中文](README.md)
 
 Invoke ChatGPT from the command line.
 
-## Installation
+## Installation and Configuration
 
 ```bash
 pip install askchat --upgrade
 ```
 
-## How to Use
-
-Run simply with the default environment variables:
+Configure environment variables:
 
 ```bash
-ask hello
+export OPENAI_API_KEY="your-api-key"
+export OPENAI_API_BASE_URL="https://api.openai.com"
+export OPENAI_API_BASE="https://api.openai.com/v1"
+export OPENAI_MODEL="gpt-3.5-turbo"
 ```
 
-Specify other options via `askchat`:
+Note: The `OPENAI_API_BASE` variable takes precedence over `OPENAI_API_BASE_URL`. Use one of them as needed.
+
+## Usage
+
+To run with the default environment variables:
 
 ```bash
-# Ask using a specific model
-askchat hello -m "baichuan2" --base-url "localhost:8000"
+ask hello
 ```
 
-Generate a default configuration file via environment variables, edit the configuration in `~/.askchat/.env`:
+## AskChat
+
+Use `askchat` for more flexibility with parameters and to manage conversations, with related files saved under `~/.askchat/`. Supported options include:
 
 ```bash
-askchat --generate-config
+❯ askchat --help
+Usage: askchat [OPTIONS] [MESSAGE]...
+
+  Interact with ChatGPT in terminal via chattool
+
+Options:
+  -m, --model TEXT     Model name
+  -b, --base-url TEXT  Base URL of the API (without suffix `/v1`)
+  --api-base TEXT      Base URL of the API (with suffix `/v1`)
+  -a, --api-key TEXT   OpenAI API key
+  -u, --use-env TEXT   Use environment variables from the ENV_PATH
+  -c                   Continue the last conversation
+  -r, --regenerate     Regenerate the last conversation
+  -l, --load TEXT      Load the conversation from a file
+  -p, --print          Print the last conversation or a specific conversation
+  -s, --save TEXT      Save the conversation to a file
+  -d, --delete TEXT    Delete the conversation from a file
+  --list               List all the conversation files
+  --generate-config    Generate a configuration file by environment table
+  --debug              Print debug log
+  --valid-models       Print valid models that contain "gpt" in their names
+  --all-valid-models   Print all valid models
+  -v, --version        Print the version
+  --help               Show this message and exit.
 ```
 
-## Chat Options
+### Default Parameters
 
-```bash
-# Show the current version
-askchat -v
+Default parameters for the `askchat` command-line tool, used for direct interaction with ChatGPT or configuring API connection information.
 
-# Print debug logs
-askchat --debug
+| Parameter          | Example                   | Description                        |
+|--------------------|---------------------------|------------------------------------|
+| `<message>`        | `askchat hello`           | The simplest form of dialogue      |
+| `-m / --model`     | `-m gpt-3.5-turbo`        | Specify the model name             |
+| `-b / --base-url`  | `-b https://api.example.com` | Set the Base URL (excluding `/v1`) |
+| `--api-base`       | `--api-base https://api.example.com/v1` | Set the Base URL (including `/v1`) |
+| `-a / --api-key`   | `-a sk-xxxxxxx`           | Provide the OpenAI API key         |
+| `-u / --use-env`   | `-u prod`                 | Load environment variables from the specified config file, see `chatenv` |
 
-# Get valid models that include "gpt"
-askchat --valid-models
+Note: For some model APIs, like ChatGPT, `/v4` is used as the base path of the API. In such cases, use the `--api-base` parameter.
 
-# Get all valid models
-askchat --all-valid-models
-```
+### Conversation Management
 
+Conversation management parameters allow users to save, load, delete, and list conversation histories, as well as continue a previous conversation.
 
-## Managing Conversation History
+| Parameter              | Example                         | Description                                    |
+|------------------------|---------------------------------|------------------------------------------------|
+| `-c`                   | `askchat -c`                    | Continue the last conversation                 |
+| `-r / --regenerate`    | `askchat -r`                    | Regenerate the last response of the conversation |
+| `-l / --load`          | `askchat -l conversation1`      | Load conversation history from a file and continue |
+| `-p / --print`         | `askchat -p [name]`             | Print
 
-Manage conversations using `askchat`:
+ the last or a specified conversation history |
+| `-s / --save`          | `askchat -s conversation1`      | Save the current conversation history to a file   |
+| `-d / --delete`        | `askchat -d conversation1`      | Delete a specified conversation history file     |
+| `--list`               | `askchat --list`                | List all saved conversation history files        |
 
-```bash
-askchat hello
-# Continue the last conversation: -c
-askchat -c please tell me a joke
-# Regenerate the last conversation: -r
-askchat -r
-# Modify and regenerate the last conversation: -r
-askchat -r give me some jokes please
-# Save the conversation: -s/--save
-askchat -s joke
-# Load a conversation: -l/--load
-askchat -l joke
-# Delete a conversation: -d/--delete
-askchat -d joke
-# List all saved conversations: --list
-askchat --list
-# Print the last conversation: -p/--print
-askchat -p
-# Print a specific conversation: -p/--print
-askchat -p joke
-```
+All conversations are saved in `~/.askchat/`, with the most recent conversation saved in `~/.askchat/_last_chat.json`.
 
-## Managing Environment Configuration
+### Other Options
 
-Manage different environment configurations with `chatenv`:
+These options provide auxiliary functions, such as generating configuration files, printing debug logs, listing models, and showing version information.
 
-```bash
-# Create a new environment
-chatenv create <name> [--api-key "<api_key>"] [--base-url "<base_url>"] [--api-base "<api_base>"] [--model "<model_name>"]
+| Parameter                | Example                       | Description                                |
+|--------------------------|-------------------------------|--------------------------------------------|
+| `--generate-config`      | `askchat --generate-config`   | Generate a config file, saved in `~/.askchat/.env` |
+| `--debug`                | `askchat --debug`             | Print debug logs                           |
+| `--valid-models`         | `askchat --valid-models`      | Print valid models containing "gpt" in their names |
+| `--all-valid-models`     | `askchat --all-valid-models`  | Print all valid models                     |
+| `-v / --version`         | `askchat -v`                  | Print the version of `askchat`             |
+
+Note: `--all-valid-models` prints all available models, including Embedding, dalle-3, tts, etc. Use `--valid-models` to filter these out.
+
+## ChatEnv
+
+`chatenv` is a command-line tool designed for managing different environment configurations for `askchat`, supporting operations such as create, activate, delete, etc. It facilitates switching between different environments, managing API keys, model names, and API base URLs.
+
+1. Create a new environment configuration using the `create` command.
+
+    ```bash
+    chatenv create <name> [-a API_KEY] [-b BASE_URL] [--api-base API_BASE] [-m MODEL]
+    ```
+
+2. Activate an environment, setting it as the current configuration.
+
+    ```bash
+    chatenv use <name>
+    ```
+
+3. Delete a specified environment configuration file.
+
+    ```bash
+    chatenv delete <name>
+    chatenv delete --default
+    ```
+
+4. List all available environments.
+
+    ```bash
+    chatenv list
+    ```
 
-# Activate a specified environment
-chatenv use <name>
+5. Display the configuration information of a specified environment, or the default environment if no name is provided.
 
-# Update environment configuration
-chatenv config [<name>] [--api-key "<new_api_key>"] [--base-url "<new_base_url>"] [--api-base "<new_api_base>"] [--model "<new_model_name>"]
+    ```bash
+    chatenv show [name]
+    ```
 
-# List all environments
-chatenv list
+6. Save the currently active environment configuration to a file with a specified name.
 
-# Show variables of a specified or default environment
-chatenv show [<name>]
+    ```bash
+    chatenv save <name>
+    ```
 
-# Save the current environment as a new environment file
-chatenv save <name>
+7. Update one or more settings of a specified or default environment configuration.
 
-# Delete a specified or the default environment configuration
-chatenv delete [<name>] [--default]
-```
\ No newline at end of file
+    ```bash
+    chatenv config [name] [-a API_KEY] [-b BASE_URL] [--api-base API_BASE] [-m MODEL]
+    ```
\ No newline at end of file
diff --git a/README.md b/README.md
index b454970..c9cbfbe 100644
--- a/README.md
+++ b/README.md
@@ -9,100 +9,150 @@
 
 在命令行中调用 ChatGPT。
 
-## 安装
+## 安装及配置
 
 ```bash
 pip install askchat --upgrade
 ```
 
+配置环境变量：
+
+```bash
+export OPENAI_API_KEY="your-api-key"
+export OPENAI_API_BASE_URL="https://api.openai.com"
+export OPENAI_API_BASE="https://api.openai.com/v1"
+export OPENAI_MODEL="gpt-3.5-turbo"
+```
+
+注：`OPENAI_API_BASE` 变量优先于 `OPENAI_API_BASE_URL` 变量，二者选一即可。
+
 ## 使用方法
 
-使用默认的环境变量进行简单运行：
+使用默认的环境变量简单地运行：
 
 ```bash
 ask hello
 ```
 
-通过 `askchat` 指定其他选项：
+## AskChat
+
+通过 `askchat` 更灵活地使用参数和管理对话，工作目录为 `~/.askchat/`，支持选项如下：
 
 ```bash
-# 使用特定模型提问
-askchat hello -m "baichuan2" --base-url "localhost:8000"
+❯ askchat --help
+Usage: askchat [OPTIONS] [MESSAGE]...
+
+  Interact with ChatGPT in terminal via chattool
+
+Options:
+  -m, --model TEXT     Model name
+  -b, --base-url TEXT  Base URL of the API (without suffix `/v1`)
+  --api-base TEXT      Base URL of the API (with suffix `/v1`)
+  -a, --api-key TEXT   OpenAI API key
+  -u, --use-env TEXT   Use environment variables from the ENV_PATH
+  -c                   Continue the last conversation
+  -r, --regenerate     Regenerate the last conversation
+  -l, --load TEXT      Load the conversation from a file
+  -p, --print          Print the last conversation or a specific conversation
+  -s, --save TEXT      Save the conversation to a file
+  -d, --delete TEXT    Delete the conversation from a file
+  --list               List all the conversation files
+  --generate-config    Generate a configuration file by environment table
+  --debug              Print debug log
+  --valid-models       Print valid models that contain "gpt" in their names
+  --all-valid-models   Print all valid models
+  -v, --version        Print the version
+  --help               Show this message and exit.
 ```
 
-通过环境变量生成默认的配置文件，在 `~/.askchat/.env` 中编辑配置：
+### 默认参数
 
-```bash
-askchat --generate-config
-```
+`askchat` 命令行工具的默认参数，这些参数用于直接与 ChatGPT 交互或者配置 API 的连接信息。
 
-## 聊天选项
+| 参数            | 示例            | 解释                               |
+|-----------------|-----------------|-----------------------------------|
+| `<message>`     | `askchat hello` | 最简单的对话          |
+| `-m / --model`  | `-m gpt-3.5-turbo` | 指定使用的模型名称                  |
+| `-b / --base-url` | `-b https://api.example.com` | 设置 Base URL (不包含 `/v1`) |
+| `--api-base`    | `--api-base https://api.example.com/v1` | 设置 Base URL (包含 `/v1`)  |
+| `-a / --api-key` | `-a sk-xxxxxxx` | 提供 OpenAI API 密钥                |
+| `-u / --use-env` | `-u prod` | 使用指定配置文件加载环境变量，详见 `chatenv`     |
 
-```bash
-# 显示当前版本
-askchat -v
+注：一些模型 API，比如智谱，使用 `/v4` 作为 API 的基础路径，这时可以使用 `--api-base` 参数。
 
-# 打印调试日志
-askchat --debug
+### 对话管理
 
-# 获取包含 "gpt" 的有效模型
-askchat --valid-models
+对话管理参数允许用户保存、加载、删除和列出对话历史记录，以及继续之前的对话。
 
-# 获取所有有效模型
-askchat --all-valid-models
-```
+| 参数                | 示例             | 解释                                       |
+|---------------------|------------------|--------------------------------------------|
+| `-c`                | `askchat -c`     | 继续上一次的对话                             |
+| `-r / --regenerate` | `askchat -r`     | 重新生成上一次对话的最后回复                   |
+| `-l / --load`       | `askchat -l conversation1` | 从文件加载对话历史，继续对话                  |
+| `-p / --print`      | `askchat -p [name]`     | 打印上次或指定的对话历史                       |
+| `-s / --save`       | `askchat -s conversation1` | 将当前对话历史保存到文件                      |
+| `-d / --delete`     | `askchat -d conversation1` | 删除指定的对话历史文件                        |
+| `--list`            | `askchat --list` | 列出所有保存的对话历史文件                     |
 
+所有对话保存在 `~/.askchat/`，使用 `askchat` 的最近一次对话保存在 `~/.askchat/_last_chat.json` 文件。
 
-## 管理对话记录
+### 其他选项
 
-使用 `askchat` 管理对话：
+这些选项提供了一些辅助功能，如生成配置文件、调试日志、打印模型列表和显示版本信息。
 
-```bash
-askchat hello
-# 继续上一次对话：-c
-askchat -c 请给我讲个笑话
-# 重新生成最后一次对话：-r
-askchat -r
-# 修改并重新生成最后一次对话：-r
-askchat -r give me some jokes please
-# 保存对话：-s/--save
-askchat -s joke
-# 加载对话：-l/--load
-askchat -l joke
-# 删除对话：-d/--delete
-askchat -d joke
-# 列出所有保存的对话：--list
-askchat --list
-# 打印最后一次对话：-p/--print
-askchat -p
-# 打印指定的对话：-p/--print
-askchat -p joke
-```
+| 参数                      | 示例                 | 解释                                       |
+|---------------------------|----------------------|--------------------------------------------|
+| `--generate-config`       | `askchat --generate-config` | 生成配置文件，保存在 `~/.askchat/.env` 中  |
+| `--debug`                 | `askchat --debug`    | 打印调试日志                                |
+| `--valid-models`          | `askchat --valid-models` | 打印包含 "gpt" 名称的有效模型列表            |
+| `--all-valid-models`      | `askchat --all-valid-models` | 打印所有有效的模型列表                     |
+| `-v / --version`          | `askchat -v`         | 打印 `askchat` 的版本信息                    |
 
-## 管理环境配置
+注：`--all-valid-models` 会打印所有可用模型，包括 Embedding, dalle-3, tts 等，使用 `--valid-models` 可以过滤掉这些。
 
-通过 `chatenv` 管理不同的环境配置：
+## ChatEnv
 
-```bash
-# 创建新环境
-chatenv create <name> [--api-key "<api_key>"] [--base-url "<base_url>"] [--api-base "<api_base>"] [--model "<model_name>"]
+`chatenv` 用于管理不同的环境配置，支持创建、激活、删除等操作，便于在不同的环境之间切换，管理 API 密钥、模型名称和 API 的基础 URL 等配置信息。
 
-# 激活指定环境
-chatenv use <name>
+1. 创建一个新的环境配置，使用 `create` 命令。
 
-# 更新环境配置
-chatenv config [<name>] [--api-key "<new_api_key>"] [--base-url "<new_base_url>"] [--api-base "<new_api_base>"] [--model "<new_model_name>"]
+    ```bash
+    chatenv create <name> [-a API_KEY] [-b BASE_URL] [--api-base API_BASE] [-m MODEL]
+    ```
 
-# 列出所有环境
-chatenv list
+2. 激活某个环境，将其设置为当前使用的配置。
 
-# 显示指定环境或默认环境的变量
-chatenv show [<name>]
+    ```bash
+    chatenv use <name>
+    ```
 
-# 保存当前环境为一个新的环境文件
-chatenv save <name>
+3. 删除指定的环境配置文件。
 
-# 删除指定的环境或默认环境配置
-chatenv delete [<name>] [--default]
-```
+    ```bash
+    chatenv delete <name>
+    chatenv delete --default
+    ```
+
+4. 列出当前所有可用环境。
+
+    ```bash
+    chatenv list
+    ```
+
+5. 显示指定环境的配置信息，如果没有指定环境名称，则显示默认环境的配置。
+
+    ```bash
+    chatenv show [name]
+    ```
+
+6. 将当前激活的环境配置保存为指定名称的配置文件。
+
+    ```bash
+    chatenv save <name>
+    ```
+
+7. 更新指定或默认环境配置的一项或多项设置。
 
+    ```bash
+    chatenv config [name] [-a API_KEY] [-b BASE_URL] [--api-base API_BASE] [-m MODEL]
+    ```
\ No newline at end of file
diff --git a/askchat/askchat.py b/askchat/askchat.py
index 6e472e9..e0617ba 100644
--- a/askchat/askchat.py
+++ b/askchat/askchat.py
@@ -15,6 +15,7 @@
 CONFIG_PATH = Path.home() / ".askchat"
 CONFIG_FILE = CONFIG_PATH / ".env"
 LAST_CHAT_FILE = CONFIG_PATH / "_last_chat.json"
+ENV_PATH = Path.home() / '.askchat' / 'envs'
 
 def setup():
     """Application setup: Ensure that necessary folders and files exist."""
@@ -22,26 +23,78 @@ def setup():
     if not os.path.exists(CONFIG_FILE):
         with open(CONFIG_FILE, 'w') as cf:
             cf.write("# Initial configuration\n")
+    load_dotenv(CONFIG_FILE, override=True)
     # if not os.path.exists(LAST_CHAT_FILE):
     #     with open(LAST_CHAT_FILE, 'w') as lcf:
     #         lcf.write('{"index": 0, "chat_log": []}')
 
-def _generate_config():
+# callback functions
+def generate_config_callback(ctx, param, value):
     """Generate a configuration file by environment table."""
+    if not value:
+        return
     api_key, model = os.getenv("OPENAI_API_KEY"), os.getenv("OPENAI_API_MODEL")
     base_url, api_base = os.getenv("OPENAI_API_BASE_URL"), os.getenv("OPENAI_API_BASE")
-    
-    # move the old config file to a temporary file
-    if os.path.exists(CONFIG_FILE):
-        # move the old config file to a temporary file
-        os.makedirs("/tmp", exist_ok=True)
-        tmp_file = os.path.join("/tmp", str(uuid.uuid4())[:8] + ".askchat.env")
-        shutil.move(CONFIG_FILE, tmp_file)
-        print(f"Moved old config file to {tmp_file}")
-        # save the config file
+    # save the config file
     write_config(CONFIG_FILE, api_key, model, base_url, api_base)
     print("Created config file at", CONFIG_FILE)
-    return
+    ctx.exit()
+
+def debug_log_callback(ctx, param, value):
+    if not value:
+        return
+    debug_log()
+    ctx.exit()
+
+def valid_models_callback(ctx, param, value):
+    if not value:
+        return
+    click.echo('Valid models that contain "gpt" in their names:')
+    click.echo(pprint(Chat().get_valid_models()))
+    ctx.exit()
+
+def all_valid_models_callback(ctx, param, value):
+    if not value:
+        return
+    click.echo('All valid models:')
+    click.echo(pprint(Chat().get_valid_models(gpt_only=False)))
+    ctx.exit()
+
+def version_callback(ctx, param, value):
+    if not value:
+        return
+    click.echo(f"askchat version: {VERSION}")
+    ctx.exit()
+
+# callback functions for handling chat history
+def save_chat_callback(ctx, param, value):
+    if not value:
+        return
+    try:
+        shutil.copyfile(LAST_CHAT_FILE, CONFIG_PATH / f"{value}.json")
+        click.echo(f"Saved conversation to {CONFIG_PATH}/{value}.json")
+    except FileNotFoundError:
+        click.echo("No last conversation to save.")
+    ctx.exit()
+
+def delete_chat_callback(ctx, param, value):
+    if not value:
+        return
+    try:
+        os.remove(CONFIG_PATH / f"{value}.json")
+        click.echo(f"Deleted conversation at {CONFIG_PATH}/{value}.json")
+    except FileNotFoundError:
+        click.echo(f"The specified conversation {CONFIG_PATH}/{value}.json does not exist.")
+    ctx.exit()
+
+def list_chats_callback(ctx, param, value):
+    if not value:
+        return
+    click.echo("All conversation files:")
+    for file in CONFIG_PATH.glob("*.json"):
+        if not file.name.startswith("_"):
+            click.echo(f" - {file.stem}")
+    ctx.exit()
 
 @click.group()
 def cli():
@@ -54,31 +107,34 @@ def cli():
 @click.option('-b', '--base-url', default=None, help='Base URL of the API (without suffix `/v1`)')
 @click.option('--api-base', default=None, help='Base URL of the API (with suffix `/v1`)')
 @click.option('-a', '--api-key', default=None, help='OpenAI API key')
+@click.option('-u', '--use-env', default=None, help='Use environment variables from the ENV_PATH')
 # Chat with history
 @click.option('-c', is_flag=True, help='Continue the last conversation')
 @click.option('-r', '--regenerate', is_flag=True, help='Regenerate the last conversation')
-@click.option('-s', '--save', default=None, help='Save the conversation to a file')
 @click.option('-l', '--load', default=None, help='Load the conversation from a file')
+# Handling chat history
 @click.option('-p', '--print', is_flag=True, help='Print the last conversation or a specific conversation')
-@click.option('-d', '--delete', default=None, help='Delete the conversation from a file')
-@click.option('--list', is_flag=True, help='List all the conversation files')
+@click.option('-s', '--save', callback=save_chat_callback, expose_value=False, help='Save the conversation to a file')
+@click.option('-d', '--delete', callback=delete_chat_callback, expose_value=False, help='Delete the conversation from a file')
+@click.option('--list', is_flag=True, callback=list_chats_callback, expose_value=False, help='List all the conversation files')
 # Other options
-@click.option('--generate-config', is_flag=True, help='Generate a configuration file by environment table')
-@click.option('--debug', is_flag=True, help='Print debug log')
-@click.option('--valid-models', is_flag=True, help='Print valid models that contain "gpt" in their names')
-@click.option('--all-valid-models', is_flag=True, help='Print all valid models')
-@click.option('-v', '--version', is_flag=True, help='Print the version')
-def main( message, model, base_url, api_base, api_key
-           , c, regenerate, save, load, print, delete, list
-           , generate_config, debug, valid_models, all_valid_models, version):
+@click.option('--generate-config', is_flag=True, callback=generate_config_callback, expose_value=False, help='Generate a configuration file by environment table')
+@click.option('--debug', is_flag=True, callback=debug_log_callback, expose_value=False, help='Print debug log')
+@click.option('--valid-models', is_flag=True, callback=valid_models_callback, expose_value=False, help='Print valid models that contain "gpt" in their names')
+@click.option('--all-valid-models', is_flag=True, callback=all_valid_models_callback, expose_value=False, help='Print all valid models')
+@click.option('-v', '--version', is_flag=True, callback=version_callback, expose_value=False, help='Print the version')
+def main( message, model, base_url, api_base, api_key, use_env
+        , c, regenerate, load, print):
     """Interact with ChatGPT in terminal via chattool"""
-    message_text = ' '.join(message).strip()
-    
+    # read environment variables from the ENV_PATH
+    if use_env:
+        env_file = ENV_PATH / f"{use_env}.env"
+        if env_file.exists():
+            load_dotenv(env_file, override=True)
+        else:
+            click.echo(f"Environment file {env_file} does not exist.")
+            return
     # set values for the environment variables
-    ## 1. read from config file `~/.askchat/.env`
-    if os.path.exists(CONFIG_FILE):
-        load_dotenv(CONFIG_FILE, override=True)
-    ## 2. read from command line
     if api_key:
         os.environ['OPENAI_API_KEY'] = api_key
     if base_url:
@@ -87,52 +143,9 @@ def main( message, model, base_url, api_base, api_key
         os.environ['OPENAI_API_BASE'] = api_base
     if model:
         os.environ['OPENAI_API_MODEL'] = model
-    # generate config file
-    if generate_config:
-        return _generate_config()
-    # update environment variables for chattool
-    chattool.load_envs()
-    # show debug log
-    if debug:
-        return debug_log()
-    # show valid models
-    if valid_models:
-        click.echo('Valid models that contain "gpt" in their names:')
-        click.echo(pprint(Chat().get_valid_models()))
-        return
-    if all_valid_models:
-        click.echo('All valid models:')
-        click.echo(pprint(Chat().get_valid_models(gpt_only=False)))
-        return
-    # Handle chat history operations
-    if load:
-        try:
-            shutil.copyfile(CONFIG_PATH / f"{load}.json", LAST_CHAT_FILE)
-            click.echo(f"Loaded conversation from {CONFIG_PATH}/{load}.json")
-        except FileNotFoundError:
-            click.echo(f"The specified conversation {load} does not exist." +\
-                       "Please check the chat list with `--list` option.")
-        return
-    if save:
-        try:
-            shutil.copyfile(LAST_CHAT_FILE, CONFIG_PATH / f"{save}.json")
-            click.echo(f"Saved conversation to {CONFIG_PATH}/{save}.json")
-        except FileNotFoundError:
-            click.echo("No last conversation to save.")
-        return
-    if delete:
-        try:
-            os.remove(CONFIG_PATH / f"{delete}.json")
-            click.echo(f"Deleted conversation at {CONFIG_PATH}/{delete}.json")
-        except FileNotFoundError:
-            click.echo(f"The specified conversation {CONFIG_PATH}/{delete}.json does not exist.")
-        return
-    if list:
-        click.echo("All conversation files:")
-        for file in CONFIG_PATH.glob("*.json"):
-            if not file.name.startswith("_"):
-                click.echo(f" - {file.stem}")
-        return
+    chattool.load_envs() # update the environment variables in chattool
+    # print chat messages
+    message_text = ' '.join(message).strip()
     if print:
         fname = message_text if message_text else '_last_chat'
         fname = f"{CONFIG_PATH}/{fname}.json"
@@ -141,29 +154,45 @@ def main( message, model, base_url, api_base, api_key
         except FileNotFoundError:
             click.echo(f"The specified conversation {fname} does not exist.")
         return
-    # Handle version option
-    if version:
-        click.echo(f"askchat version: {VERSION}")
-        return
-    # Main chat
+    # handling chat history | Four cases: regenerate, load, continue, default
     chat = Chat()
-    if c or regenerate: # Load last chat if -c or -r is used
+    if regenerate:
         try:
             chat = Chat.load(LAST_CHAT_FILE)
         except FileNotFoundError:
             click.echo("No last conversation found. Starting a new conversation.")
             return
-    if regenerate:
         if len(chat) < 2:
             click.echo("You should have at least two messages in the conversation")
             return
         chat.pop()
+    elif load: # load and continue the conversation
+        try:
+            shutil.copyfile(CONFIG_PATH / f"{load}.json", LAST_CHAT_FILE)
+            click.echo(f"Loaded conversation from {CONFIG_PATH}/{load}.json")
+        except FileNotFoundError:
+            click.echo(f"The specified conversation {load} does not exist." +\
+                       "Please check the chat list with `--list` option.")
+        if not message_text: # if no message is provided, just quit
+            return
+        chat = Chat.load(LAST_CHAT_FILE)
+        chat.user(message_text)
+    elif c: # continue the last conversation
+        if not message_text:
+            click.echo("Please specify message!")
+            return
+        try:
+            chat = Chat.load(LAST_CHAT_FILE)
+        except FileNotFoundError:
+            click.echo("No last conversation found. Starting a new conversation.")
+            return
+        chat.user(message_text)
     else:
         if not message_text:
             click.echo("Please specify message!")
             return
         chat.user(message_text)
-    # Simulate chat response
+    # Add chat response
     chat.assistant(asyncio.run(show_resp(chat)))
     chat.save(LAST_CHAT_FILE, mode='w')