codex-chat-bot

A small Python chat project with:

• a Python programming interface
• a command-line interface
• single-session memory
• local image attachments for vision-capable models
• configurable API key, base URL, model, and system rules

The project uses OpenAI SDK-compatible Chat Completions API endpoints.

Installation

python -m pip install codex-chat-bot

Environment Variables

Only CODEX_CHAT_* environment variables are read:

export CODEX_CHAT_API_KEY="your API key"
export CODEX_CHAT_BASE_URL="https://api.openai.com/v1"
export CODEX_CHAT_MODEL="gpt-5.5"                       # optional
export CODEX_CHAT_TIMEOUT="600"                          # optional, seconds
export CODEX_CHAT_MAX_COMPLETION_TOKENS="1024"            # optional

Requests use a default timeout of 600 seconds. Set CODEX_CHAT_TIMEOUT to override it for slower or faster endpoints. If an environment value is surrounded by one matching pair of single or double quotes, that outer pair is removed automatically. Unmatched quotes are kept.

CODEX_CHAT_BASE_URL must be the API root, not the provider's Web UI address. For OpenAI-compatible gateways this commonly ends in /v1. If the endpoint returns an HTML page, the client raises InvalidEndpointResponseError with a configuration hint.

When a real ChatSession creates its SDK client and the configured URL does not already end in /v1, it probes the current /models endpoint first and then the /v1/models candidate. It appends /v1 only when the candidate is a recognizable JSON API endpoint and the original is not. These probes do not create model completions or consume completion tokens.

JSON Config File

You can also load api_key, base_url, model, and system_rules from a UTF-8 JSON file:

{
    "api_key": "your API key",
    "base_url": "https://api.openai.com/v1",
    "model": "gpt-5.5",
    "system_rules": [
        "You are a concise programming assistant.",
        "Answer in English."
    ]
}

Use --config or --config-file to choose the file:

codex-chat --config ./config.json "Hello"

Values from the config file are used before environment variables and command line options, so CODEX_CHAT_* variables and explicit flags can still override the file for one run.

Command-Line Usage

Run a single chat turn:

codex-chat "Write a Python hello world example."

Start interactive chat:

codex-chat

If codex-chat is not on your PATH, run the module directly:

python -m codex_chat_bot.cli
python -m codex_chat_bot.cli "Hello"

Interactive commands:

• /name NAME changes the name used for your next messages. The default name is user.
• /reset clears the current session memory.
• /import PATH loads chat history from a JSON file.
• /export PATH saves chat history to a JSON file.
• /exit or /quit exits the chat.

Common options:

codex-chat --api-key "your API key" --base-url "https://api.openai.com/v1" "Hello"
codex-chat --config ./config.json "Hello"
codex-chat --model gpt-5.5 --system "You are a concise programming assistant."
codex-chat --system-rule "Answer in English." --system-rule "Keep answers short." "Explain pytest."
codex-chat --system-rules-file ./rules.txt "Review this idea."
codex-chat --bind-history ./history.json "Continue our chat."
codex-chat --base-url "https://api.openai.com/v1" "Explain pytest."

If CODEX_CHAT_API_KEY or CODEX_CHAT_BASE_URL is not set and the value was not passed on the command line, interactive CLI startup prompts for the missing value.

--bind-history loads the JSON file if it already exists, creates an empty history file if it does not, and writes every new message to that file as the chat changes. If the file exists but is not valid chat history JSON, the CLI prints a warning and recreates it as an empty history file.

Python API

The object-oriented API is built around ChatConfig, ChatSession, Message, and ImageAttachment. See the complete Python API guide for lifecycle, persistence, error handling, and extension details.

Text messages

from codex_chat_bot import ChatConfig, ChatSession

session = ChatSession(ChatConfig.from_env())

print(session.ask("Remember that my project is named codex-chat-bot."))
print(session.ask("What is my project called?"))
print(session.ask("This is Alice speaking.", username="alice"))

session.bind_history("history.json")
session.ask("This message is saved automatically.")

Local image attachments

Pass one local path directly to images=. The file is read immediately and embedded as a Base64 data URL in the Chat Completions request, so no public URL or separate file-hosting service is needed:

from codex_chat_bot import ChatConfig, ChatSession

session = ChatSession(ChatConfig.from_env())
answer = session.ask(
    "Read the chart and summarize its trend.",
    images="./chart.png",
)
print(answer)

For multiple images or explicit control over image detail, create reusable ImageAttachment objects:

from codex_chat_bot import ChatConfig, ChatSession, ImageAttachment

session = ChatSession(ChatConfig.from_env())
diagram = ImageAttachment.from_file("./architecture.png", detail="high")

response = session.send(
    "Compare these two diagrams.",
    images=[diagram, "./architecture-v2.webp"],
)
print(response.text)

Supported local formats are PNG, JPEG, WEBP, and GIF. The configured model and OpenAI-compatible endpoint must also support image input. detail can be "auto", "low", or "high".

images= explicitly accepts None, [], one path string, or a list of path strings. None and [] both send a normal text-only message; list order is preserved for multiple images.

To construct the complete message object yourself, use Message.user() and send_message():

from codex_chat_bot import ImageAttachment, Message

message = Message.user(
    "Inspect this screenshot.",
    username="alice",
    images=(ImageAttachment.from_file("./screen.png"),),
)
response = session.send_message(message)

You can also pass configuration explicitly:

from codex_chat_bot import ChatConfig, ChatSession

config = ChatConfig(
    api_key="your API key",
    base_url="https://api.openai.com/v1",
    model="gpt-5.5",
    timeout=600,
    system_rules=(
        "You are a patient Python programming assistant.",
        "Answer in English.",
        "Keep code examples runnable.",
    ),
)

session = ChatSession(config)
answer = session.ask("Write a function that reads a JSON file.")
print(answer)

system_rules are added to the session's initial system message and stay active until the session is reset.

Pass username= to ask() or send() to distinguish different people in one session. User messages are sent to the model with the speaker name included, and chat history stores each message's username.

Chat history JSON uses a top-level messages array:

{
    "messages": [
        { "role": "system", "content": "You are a helpful assistant.", "username": "system" },
        { "role": "user", "content": "Hello", "username": "alice" },
        { "role": "assistant", "content": "Hi!", "username": "assistant" }
    ]
}

Messages with images include an images array containing the media type, detail level, filename, and Base64 image bytes. This makes an exported history self-contained, but it can be large and should be protected as sensitive data.

Tests

python -m pytest