OpenBitFun (formerly BitFun) is an open-source agent workspace with a desktop app, a CLI, mobile clients, and messaging bots. A Rust agent runtime manages session state, context, and tool execution, with persistent sessions, interruption recovery, long-term memory, context compression, and cache reuse for long-running tasks.
The agent harness plans steps, manages context, calls tools, coordinates agents, and combines their results. It runs in one of four modes:
| Mode | Use |
|---|---|
| Minimal | Quick collaboration: the agent acts directly and you refine the work together |
| Standard | Everyday multi-step tasks: plan, work through, and check results |
| Ultimate | Complex tasks divided among several agents |
| Creative | Building Mini Apps or extending the workspace itself |
Work continues on the device that runs the task while you check progress, add instructions, or answer approval requests from a phone or a browser. Account login and sync between devices run through a self-deployed relay server, and SSH connections run agents on a remote host, through a jump host, or inside a container. In a DeepSWE v1.1 evaluation, OpenBitFun reached a 64.6% pass rate with GLM-5.3-Flash and 56.6% with DeepSeek-V4-Flash.
Features
- Harness modes: Minimal, Standard, Ultimate, and Creative modes for different kinds of work
- Cross-device control: start on desktop and continue from a phone or browser, with one-, two-, or three-screen mobile layouts
- Remote workspaces: SSH to a remote host, through a jump host, or into a container
- Mini Apps: describe a need and the agent builds an app that pairs an interface with an agent conversation, with a marketplace for sharing
- Specialist agents: choose a model, define a role, and attach tools and workflows
- Extensibility: MCP tools, Skills, Hooks, skins, and source changes, including having the Code Agent modify OpenBitFun itself
- Long-running tasks: persistent sessions, interruption recovery, long-term memory, and context compression
