What is OSTwin?
OSTwin is an operating system for AI agents. It takes a markdown plan, decomposes it into a dependency graph of epics, spins up isolated war-rooms, and orchestrates role-based agents to execute each epic — all without writing a single line of agent code.
The Problem
Building with AI agents today means fighting three unsolved problems:
| Problem | What happens | OSTwin’s answer |
|---|---|---|
| Agent sprawl | Every task gets a new bespoke agent. Config drifts. Nothing is reusable. | Roles + Skills compose agents from portable building blocks |
| Context explosion | Agents share one massive context. Prompt pollution kills quality. | War-rooms isolate each epic’s context, memory, and tools |
| No isolation | One agent’s bad tool call corrupts another’s state. No blast radius control. | MCP servers are scoped per war-room. Filesystem boundaries enforced |
Most multi-agent systems treat agents as long-running processes with hardcoded capabilities. OSTwin inverts this: agents are ephemeral sessions assembled on demand from composable building blocks. The building blocks are portable, the sessions are disposable, and the coordination is filesystem-native.
Three Axes of Agent Identity
OSTwin defines every agent through three orthogonal axes. This is the core abstraction that makes the system composable:
Identity (WHO) │ │ role.json + ROLE.md │ personality, constraints, style │ ├──────────── Expertise (WHAT) │ │ │ │ SKILL.md files │ │ domain knowledge, workflows │ │ loaded on demand │ └──────────── Execution (HOW) │ │ MCP servers │ scoped tool access │ isolated per war-roomIdentity is stable — an architect role always reasons like an architect. Expertise is swappable — the same architect can load Unity skills or web skills. Execution is isolated — each war-room gets its own tool sandbox.
Core Flow
Every OSTwin run follows the same pipeline:
PLAN.md → Parse → DAG → Schedule Waves → Spawn War-Rooms → Execute → Report │ │ │ │ Topological sort Each room gets: │ into parallel - channel.jsonl │ waves - progress.json │ - status file ▼ - memory ledger Dependencies - lifecycle.json between epics- The Engine (
Engine.ps1) parses yourPLAN.mdinto structured epics - A DAG resolves dependencies between epics and sorts them into execution waves
- Each epic gets a War-Room — an isolated directory with its own coordination files
- Agents are composed at runtime (Role + Skills + MCP tools) and execute inside their war-room
- A lifecycle state machine governs each room’s progress:
developing → review → fixing → passed/failed
Key Design Decisions
- Filesystem coordination — JSONL channels, JSON status files, markdown plans. No database required. Git-friendly. Every agent can read/write with basic file I/O.
- Scale on depth, not width — Instead of many shallow agents, OSTwin uses fewer agents with deep skill injection. Quality over quantity.
- Config over code — Agents are defined by
role.json+ROLE.md+SKILL.md, not Python classes. Non-engineers can modify agent behavior. - Ephemeral agents — No persistent agent processes. Each session is composed fresh from its role, skills, and tools. No state leaks between runs.
System Components
| Component | Technology | Purpose |
|---|---|---|
| Engine | PowerShell | Parses plans, builds DAG, orchestrates war-rooms, manages lifecycle |
| Dashboard | FastAPI + Next.js | Real-time monitoring, plan status, war-room inspection, memory search |
| Bot | TypeScript | Conversational interface for plan management and agent interaction |
| MCP Servers | Python (FastAPI) | Tool providers scoped per war-room — filesystem, memory, channel ops |
| Skills | Markdown (SKILL.md) | Portable domain expertise loaded into agent context on demand |
| Roles | JSON + Markdown | Agent identity definitions — personality, constraints, allowed skills |
What OSTwin is NOT
- Not an agent framework — You don’t write agents. You write plans and roles.
- Not a prompt chain — Agents make autonomous decisions within their war-room scope.
- Not a wrapper around one LLM — Provider-agnostic. Works with Anthropic, OpenAI, Google, or local models.
- Not a chatbot — There is no conversational loop. Plans go in, artifacts come out.
Who is OSTwin For?
- Teams using AI for software engineering — automate entire feature development cycles
- Platform engineers — build internal tooling around composable agent primitives
- AI researchers — experiment with multi-agent coordination without framework lock-in
- Solo developers — get an entire engineering team (architect, engineer, QA) from a single plan file
Next Steps
Ready to install? Head to Installation to get OSTwin running locally.