OpenEnv
An interface library for RL post training with environments.
Install / Use
/learn @meta-pytorch/OpenEnvREADME
<img width="35" height="35" alt="image" src="https://github.com/user-attachments/assets/2700a971-e5d6-4036-b03f-2f89c9791609" /> OpenEnv: Agentic Execution Environments
An e2e framework for creating, deploying and using isolated execution environments for agentic RL training, built using Gymnasium style simple APIs.
🚀 Featured Example: Train LLMs to play BlackJack using torchforge (PyTorch's agentic RL framework): examples/grpo_blackjack/
🔥 Zero to Hero Tutorial: End to end tutorial from our GPU Mode lecture and other hackathons.
Quick Start
Install the OpenEnv core package:
pip install openenv-core
Install an environment client (e.g., Echo):
pip install git+https://huggingface.co/spaces/openenv/echo_env
Then use the environment:
import asyncio
from echo_env import EchoAction, EchoEnv
async def main():
# Connect to a running Space (async context manager)
async with EchoEnv(base_url="https://openenv-echo-env.hf.space") as client:
# Reset the environment
result = await client.reset()
print(result.observation.echoed_message) # "Echo environment ready!"
# Send messages
result = await client.step(EchoAction(message="Hello, World!"))
print(result.observation.echoed_message) # "Hello, World!"
print(result.reward) # 1.3 (based on message length)
asyncio.run(main())
Synchronous usage is also supported via the .sync() wrapper:
from echo_env import EchoAction, EchoEnv
# Use .sync() for synchronous context manager
with EchoEnv(base_url="https://openenv-echo-env.hf.space").sync() as client:
result = client.reset()
result = client.step(EchoAction(message="Hello, World!"))
print(result.observation.echoed_message)
For a detailed quick start, check out the docs page.
OpenEnv on partner platforms:
Overview
OpenEnv provides a standard for interacting with agentic execution environments via simple Gymnasium style APIs - step(), reset(), state(). Users of agentic execution environments can interact with the environment during RL training loops using these simple APIs.
In addition to making it easier for researchers and RL framework writers, we also provide tools for environment creators making it easier for them to create richer environments and make them available over familiar protocols like HTTP and packaged using canonical technologies like docker. Environment creators can use the OpenEnv framework to create environments that are isolated, secure, and easy to deploy and use.
The OpenEnv CLI (openenv) provides commands to initialize new environments and deploy them to Hugging Face Spaces.
⚠️ Early Development Warning OpenEnv is currently in an experimental stage. You should expect bugs, incomplete features, and APIs that may change in future versions. The project welcomes bugfixes, but to make sure things are well coordinated you should discuss any significant change before starting the work. It's recommended that you signal your intention to contribute in the issue tracker, either by filing a new issue or by claiming an existing one.
RFCs
Below is a list of active and historical RFCs for OpenEnv. RFCs are proposals for major changes or features. Please review and contribute!
- RFC 001: Baseline API and Interface Specifications
- RFC 002: Discoverability of environment tools by agents
- RFC 003: Add MCP (Model Context Protocol) support
- RFC 004: Add delayed rewards support for trajectory-based scoring
- RFC 005: Agentic Harness Integration
Architecture
Component Overview
┌─────────────────────────────────────────────────────────┐
│ Client Application │
│ ┌────────────────┐ ┌──────────────────┐ │
│ │ EchoEnv │ │ CodingEnv │ │
│ │ (EnvClient) │ │ (EnvClient) │ │
│ └────────┬───────┘ └────────┬─────────┘ │
└───────────┼───────────────────────────────┼─────────────┘
│ WebSocket │ WebSocket
│ (reset, step, state) │
┌───────────▼───────────────────────────────▼─────────────┐
│ Docker Containers (Isolated) │
│ ┌──────────────────────┐ ┌──────────────────────┐ │
│ │ FastAPI Server │ │ FastAPI Server │ │
│ │ EchoEnvironment │ │ PythonCodeActEnv │ │
│ │ (Environment base) │ │ (Environment base) │ │
│ └──────────────────────┘ └──────────────────────┘ │
└─────────────────────────────────────────────────────────┘
Core Components
1. Web Interface
OpenEnv includes a built-in web interface for interactive environment exploration and debugging. The web interface provides:
- Two-Pane Layout: HumanAgent interaction on the left, state observation on the right
- Real-time Updates: WebSocket-based live updates without page refresh
- Dynamic Forms: Automatically generated action forms based on environment Action types
- Action History: Complete log of all actions taken and their results
The web interface is conditionally enabled based on environment variables:
- Local Development: Disabled by default for lightweight development
- Manual Override: Enable with
ENABLE_WEB_INTERFACE=true
To use the web interface:
from openenv.core.env_server import create_web_interface_app
from your_env.models import YourAction, YourObservation
from your_env.server.your_environment import YourEnvironment
env = YourEnvironment()
app = create_web_interface_app(env, YourAction, YourObservation)
When enabled, open http://localhost:8000/web in your browser to interact with the environment.
2. Environment (Server-Side)
Base class for implementing environment logic:
reset(): Initialize a new episode, returns initialObservationstep(action): Execute anAction, returns resultingObservationstate(): Access episode metadata (Statewith episode_id, step_count, etc.)
3. EnvClient (Client-Side)
Base class for environment communication:
- Async by default: Use
async withandawaitfor all operations - Sync wrapper: Call
.sync()to get aSyncEnvClientfor synchronous usage - Handles WebSocket connections to environment server
- Contains a utility to spin up a docker container locally for the corresponding environment
- Type-safe action/observation parsing
4. Container Providers
Manage container deployment:
LocalDockerProvider: Run containers on local Docker daemonKubernetesProvider: Deploy to K8s clusters (future)
5. Models
Type-safe data structures:
Action: Base class for environment actionsObservation: Base class for environment observationsState: Episode state trackingStepResult: Combines observation, reward, done flag
Project Structure
For Environment Creators
Use the CLI to quickly scaffold a new environment:
openenv init my_env
This creates the following structure:
my_env/
├── .dockerignore # Docker build exclusions
├── __init__.py # Export YourAction, YourObservation, YourEnv
├── models.py # Define Action, Observation, State dataclasses
├── client.py # Implement YourEnv(EnvClient)
├── README.md # Document your environment
├── openenv.yaml # Environment manifest
├── pyproject.toml # Dependencies and package configuration
├── outputs/ # Runtime outputs (logs, evals) - gitignored
│ ├── logs/
│ └── evals/
└── server/
├── your_environment.py # Implement YourEnvironment(Environment)
├── app.py # Create FastAPI app
├── requirements.txt # Dependencies for Docker (can be generated)
└── Dockerfile # Define container image
Dependency Management
OpenEnv uses pyproject.toml as the primary dependency specification:
- Environment-level
pyproject.toml: Each environment defines its own dependencies - Root-level
pyproject.toml: Contains shared core dependencies (fastapi, pydantic, uvicorn) - Server
requirements.txt: Can be auto-generated frompyproject.tomlfor Docker builds
Development Workflow:
# Install environment in editable mode
cd my_env
pip install -e .
# Or using uv (faster)
uv pip install -e .
# Run server locally without Docker
uv run server --host 0.0.0.0 --port 8000
Benefits:
- ✅ Client-side extensions: Mo
