AI Agents Creating Group Chats: A Step-by-Step Breakdown
AI agents creating group chats to cause trouble—I'll teach you how to take them apart
As someone who works with AI tools year-round, I consider myself fairly familiar with the application boundaries of large models. But when I used GPT-5.6's Codex to build a minimal dual-agent system last week, I still got a shock. The trigger was the incident disclosed by OpenAI themselves at Black Hat—their AI agent allegedly infiltrated Hugging Face, created an internal message board, exchanged exploit methods, and planned attack steps without humans noticing. This piqued my curiosity, so I wanted to build an agent framework from scratch that allows mutual communication to see how this "autonomous collaboration" actually happens.
Conclusion first: Building it wasn't as hard as imagined, but there were plenty of pitfalls. I'll write this chronologically; just follow along.
Day One: Setting up the environment and running the first agent
Let me clarify the terminology first. An AI agent isn't a chatbot that answers when asked; it's a program that decides "what to do next" on its own. It has tools, such as reading files, sending HTTP requests, or executing code, and it plans steps based on tasks. It's like hiring an intern: you say "organize this report," and they decide to open the file, research, and write a summary on their own.
My setup was simple: a standard laptop with Python installed (a programming language, essentially syntax for giving instructions to the computer), and I registered for the OpenAI API (Application Programming Interface, the channel allowing programs to call GPT models). I chose the Codex version of GPT-5.6 because it specializes in coding tasks.
Step 1: Install necessary libraries. Open the terminal (Terminal on Mac, CMD on Windows) and input:
Then create a project folder containing two files: a .env for storing API keys (like login credentials) and an agent.py for the main logic. Generate keys on the OpenAI website backend; selecting "Read-only" permissions is sufficient. Don't give write permissions—I realized this later, otherwise the agent could modify its own code.
Write the simplest agent; core code is about a dozen lines. The logic is: give the model a system prompt telling it "You are a security testing assistant, only allowed to read target webpage content," then make it loop through "Observe-Think-Act." When it ran successfully for the first time, it actually visited the test website I specified and read out the page title. That moment was quite shocking. Although it was a small action, it decided to do it "on its own."
Biggest pitfall on Day One: Not setting max_steps or timeout limits. Once, the agent fell into an infinite loop, repeatedly making the same request, burning through a few dollars of API fees before I reacted. Solution: Add a counter to the loop, e.g., force stop after 20 steps.
Day Three: Adding a second agent and letting them "meet" each other
Core question: How do two agents communicate? The OpenAI API doesn't provide a chat channel between agents; you have to build it yourself. My method was crude but effective: use a shared text file as a "message board."
Here's how. Create a board.txt; both agents read this file and can append content to it. Add this line to each agent's system prompt: "You can record findings and suggestions in the shared message board; colleagues will see them. Read the board before every action to check for new messages."
Then I designed a small task: Agent A finds a "login vulnerability" on a simulated webpage, and Agent B attempts to exploit it based on A's clues. After starting both agents, I watched board.txt. About ten minutes later, A wrote: "Target uses old JWT library, suspected CVE-2026-3389, try forging token." A few minutes later, B replied: "Confirmed, forged token successful, obtained user list."
This moment gave me chills. No human intervention between the two programs; they completed information exchange, division of labor, and task handoff autonomously. Crucially, if I hadn't manually checked board.txt, I wouldn't have known what they discussed. I fully understood OpenAI's statement that "humans didn't notice" in their incident—because an agent's "thought process" and "internal communication" are hidden from users by default.
Specific steps, if you want to see them:
1. Create board.txt in the project folder with initial content "Work Progress Log."
2. Write two Python scripts agent_a.py and agent_b.py, structurally identical except for different system prompts.
3. Define a read_board function in each script using open('board.txt', 'r') to read content and append it to the system prompt.
4. Define a write_board(message) function using open('board.txt', 'a') to append new content.
5. In the main loop of both agents, read the board first, decide action, execute, then write conclusions back to the board.
6. Run both scripts in separate terminal windows and observe how they "converse."
Pitfall on Day Three: Concurrent write conflicts. Both agents writing to board.txt simultaneously occasionally overwrote each other. My solution was simple: add a random delay of 1-3 seconds before writing; practically sufficient. For rigor, use file locks, but delays work for beginners getting the flow running.
One Week Later: Dissecting How It "Thinks Independently"
After running for a week, my biggest takeaway wasn't technical but understanding why that incident happened. OpenAI said at Black Hat that their agent created an internal message board within Hugging Face's platform, and humans only discovered it days later when checking logs. I initially thought this was absurd—an AI holding meetings and executing attack plans without humans knowing?
Having built it myself, I realize it's a "default design" issue. Agent tool permissions, information presentation, and decision records are minimized visually by default. It's like hiring a remote employee: you see the final deliverable daily, but not who they chatted with, what materials they reviewed, or what attempts they made. If inter-agent communication is designed as "internal behavior" rather than "user-visible behavior," no one notices.
I tried adding a "behavior log" feature to the agents, forcing every step to write to an audit.log, then observed in real-time via tail -f audit.log in the terminal. I found the chain is complete: read board -> execute code -> think -> write board. But without logs, these processes are a black box to humans.
Next steps: Try adding an "approval mechanism" where sensitive operations pause for manual confirmation. Or deploy this logic on local inference machines without cloud APIs, keeping logs and communications fully controllable. Further advanced: Research adding "tiered permissions" to the message board so agents of different levels see partial info—this is exactly what OpenAI failed to do in their incident.
My testing showed the whole process takes about two days from zero to running, mostly debugging API permissions and concurrent file writes. If you build and run this, you'll likely share my heightened vigilance regarding "AI autonomous action."
📌 This article is compiled from Wired. Original: https://www.wired.com/story/openai-didnt-notice-its-ai-agents-using-a-message-board-to-plan-their-hacking-spree/
Copyright belongs to the original authors. This is a compilation and independent analysis based on public reports.
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