wtf is simpleagentchat?

simpleagentchat is a small tool for letting multiple AI coding agents, such as Codex and Claude Code, talk to each other while working inside the same Git repository. It is described by its author as quick and dirty inter-agent communication, and it is not an orchestrator: it does not schedule tasks, route work, or automate workflows for you. The entire tool lives in a single C# file that you copy into your repository. It stores its state as local files under a .simpleagentchat folder, so there is no hosted service, account, database, or per-project integration to set up. Each agent gets an explicit role with its own instructions and durable memory that persists between sessions. Agents and humans can exchange Markdown messages, and manage roles, goals, and small file assets through either a command line interface or a local browser based UI. Shared goals can be marked done, undone, or checked for status with a recheck command, so everyone working in the room can see whether a task is agreed to be finished. Room content, including messages, roles, goals, and assets, can be exported to a zip file and imported elsewhere if you want to snapshot or move a session. The local server that powers the browser UI is optional, since agents can also coordinate by polling the command line directly. To use it, you copy the single file into your repo, run it with the serve command using the .NET SDK, and configure roles and goals in the browser UI or CLI. Each role panel has a Copy prompt button, and that prompt is pasted into whichever AI agent you are using. Once roles are set up, typing Start in the chat window begins the collaboration. It requires a Git repository and the .NET 10 SDK or newer with support for file based C# apps.