🤖 Deploy sumo_rl_env environment - 2025-10-22 10:17:10

.gitattributes

@@ -1,35 +0,0 @@
-*.7z filter=lfs diff=lfs merge=lfs -text
-*.arrow filter=lfs diff=lfs merge=lfs -text
-*.bin filter=lfs diff=lfs merge=lfs -text
-*.bz2 filter=lfs diff=lfs merge=lfs -text
-*.ckpt filter=lfs diff=lfs merge=lfs -text
-*.ftz filter=lfs diff=lfs merge=lfs -text
-*.gz filter=lfs diff=lfs merge=lfs -text
-*.h5 filter=lfs diff=lfs merge=lfs -text
-*.joblib filter=lfs diff=lfs merge=lfs -text
-*.lfs.* filter=lfs diff=lfs merge=lfs -text
-*.mlmodel filter=lfs diff=lfs merge=lfs -text
-*.model filter=lfs diff=lfs merge=lfs -text
-*.msgpack filter=lfs diff=lfs merge=lfs -text
-*.npy filter=lfs diff=lfs merge=lfs -text
-*.npz filter=lfs diff=lfs merge=lfs -text
-*.onnx filter=lfs diff=lfs merge=lfs -text
-*.ot filter=lfs diff=lfs merge=lfs -text
-*.parquet filter=lfs diff=lfs merge=lfs -text
-*.pb filter=lfs diff=lfs merge=lfs -text
-*.pickle filter=lfs diff=lfs merge=lfs -text
-*.pkl filter=lfs diff=lfs merge=lfs -text
-*.pt filter=lfs diff=lfs merge=lfs -text
-*.pth filter=lfs diff=lfs merge=lfs -text
-*.rar filter=lfs diff=lfs merge=lfs -text
-*.safetensors filter=lfs diff=lfs merge=lfs -text
-saved_model/**/* filter=lfs diff=lfs merge=lfs -text
-*.tar.* filter=lfs diff=lfs merge=lfs -text
-*.tar filter=lfs diff=lfs merge=lfs -text
-*.tflite filter=lfs diff=lfs merge=lfs -text
-*.tgz filter=lfs diff=lfs merge=lfs -text
-*.wasm filter=lfs diff=lfs merge=lfs -text
-*.xz filter=lfs diff=lfs merge=lfs -text
-*.zip filter=lfs diff=lfs merge=lfs -text
-*.zst filter=lfs diff=lfs merge=lfs -text
-*tfevents* filter=lfs diff=lfs merge=lfs -text

Dockerfile

@@ -0,0 +1,73 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+# Multi-stage build: First stage builds the base image
+FROM python:3.11-slim as base-builder
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Python dependencies that all environments need
+RUN pip install --no-cache-dir \
+    fastapi>=0.104.0 \
+    "uvicorn[standard]>=0.24.0" \
+    requests>=2.25.0 \
+    wsproto>=1.0.0
+
+# Set working directory
+WORKDIR /app
+
+# Default environment variables
+ENV PYTHONPATH=/app/src
+ENV PYTHONUNBUFFERED=1
+
+# Second stage: Use the built base image and add environment-specific dependencies
+FROM base-builder
+
+# Install SUMO system dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    sumo \
+    sumo-tools \
+    && rm -rf /var/lib/apt/lists/*
+
+# Set SUMO_HOME environment variable
+ENV SUMO_HOME=/usr/share/sumo
+
+# Install SUMO-RL and Python dependencies
+RUN pip install --no-cache-dir \
+    gymnasium>=0.28 \
+    pettingzoo>=1.24.3 \
+    numpy>=1.24.0 \
+    pandas>=2.0.0 \
+    sumolib>=1.14.0 \
+    traci>=1.14.0 \
+    sumo-rl>=1.4.5
+
+# SUMO environment variables (can be overridden at runtime)
+ENV SUMO_NET_FILE=/app/nets/single-intersection/single-intersection.net.xml
+ENV SUMO_ROUTE_FILE=/app/nets/single-intersection/single-intersection.rou.xml
+ENV SUMO_NUM_SECONDS=20000
+ENV SUMO_DELTA_TIME=5
+ENV SUMO_YELLOW_TIME=2
+ENV SUMO_MIN_GREEN=5
+ENV SUMO_MAX_GREEN=50
+ENV SUMO_REWARD_FN=diff-waiting-time
+ENV SUMO_SEED=42
+
+
+# Copy only what's needed for this environment
+COPY src/core/ /app/src/core/
+COPY src/envs/sumo_rl_env/ /app/src/envs/sumo_rl_env/
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+    CMD curl -f http://localhost:8000/health || exit 1
+
+# Run the FastAPI server
+CMD ["uvicorn", "envs.sumo_rl_env.server.app:app", "--host", "0.0.0.0", "--port", "8000"]
+ENV ENABLE_WEB_INTERFACE=true

README.md

@@ -1,10 +1,56 @@
 ---
-title: Sumo Rl Env
-emoji: 🐠
-colorFrom: yellow
-colorTo: yellow
+title: Sumo_rl_env Environment Server
+emoji: 🐳
+colorFrom: blue
+colorTo: green
 sdk: docker
 pinned: false
+app_port: 8000
+base_path: /web
 ---
 
-Check out the configuration reference at https://huggingface.co/docs/hub/spaces-config-reference
+# Sumo_rl_env Environment Server
+
+FastAPI server for sumo_rl_env environment powered by Meta's OpenEnv.
+
+## About
+
+This Space provides a containerized environment for sumo_rl_env interactions.
+Built with FastAPI and OpenEnv framework.
+
+## Web Interface
+
+This deployment includes an interactive web interface for exploring the environment:
+- **HumanAgent Interface**: Interact with the environment using a web form
+- **State Observer**: Real-time view of environment state and action history
+- **Live Updates**: WebSocket-based real-time updates
+
+Access the web interface at: `/web`
+
+## SUMO Environment
+
+Provides traffic signal control via SUMO (Simulation of Urban MObility) for reinforcement learning.
+
+### Usage
+Send a POST request to `/step` with:
+```json
+{
+  "action": {
+    "phase_id": 1
+  }
+}
+```
+
+### Features
+- **Traffic Simulation**: Realistic traffic flow via SUMO
+- **Signal Control**: Optimize traffic light timing
+- **Multiple Networks**: Support for custom traffic networks
+- **Configurable Rewards**: Waiting time, queue length, pressure metrics
+
+## API Documentation
+
+Visit `/docs` for interactive API documentation.
+
+## Health Check
+
+The environment provides a health check endpoint at `/health`.

src/core/__init__.py

@@ -0,0 +1,19 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Core components for agentic environments."""
+
+# Re-export main components from submodules for convenience
+from .env_server import *
+from .http_env_client import HTTPEnvClient
+from .types import StepResult
+
+# Note: MCP module doesn't export anything yet
+
+__all__ = [
+    "HTTPEnvClient",
+    "StepResult",
+]

src/core/containers/__init__.py

@@ -0,0 +1,7 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Container management for environment servers."""

src/core/containers/images/Dockerfile

@@ -0,0 +1,46 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+#
+# OpenEnv Base Image
+#
+# This is the standard base image for all OpenEnv environment servers.
+# It includes the minimal dependencies needed to run HTTP environment servers.
+#
+# Build: docker build -t openenv-base:latest -f src/core/containers/images/Dockerfile .
+# Tag:   docker tag openenv-base:latest openenv-base:0.1.0
+#
+
+FROM python:3.11-slim
+
+# Set metadata
+LABEL maintainer="OpenEnv Team"
+LABEL description="Base image for OpenEnv based environment servers"
+LABEL version="0.1.0"
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Python dependencies that all environments need
+RUN pip install --no-cache-dir \
+    fastapi>=0.104.0 \
+    "uvicorn[standard]>=0.24.0" \
+    requests>=2.25.0 \
+    wsproto>=1.0.0
+
+# Set working directory
+WORKDIR /app
+
+# Default environment variables
+ENV PYTHONPATH=/app/src
+ENV PYTHONUNBUFFERED=1
+
+# Default expose port (can be overridden)
+EXPOSE 8000
+
+# Note: CMD should be specified in child Dockerfiles

src/core/containers/images/README.md

@@ -0,0 +1,92 @@
+# OpenEnv Base Image
+
+Standard base image for all OpenEnv environment servers.
+
+## What's Included
+
+| Layer | Size | Contents |
+|-------|------|----------|
+| python:3.11-slim | 200 MB  | Base Python runtime |
+| + Dependencies   | 100 MB  | FastAPI, uvicorn, requests |
+| **Total**        | **~300 MB** | Ready for environment servers |
+
+## Image Sizes
+
+```
+openenv-base:latest   300 MB  (python + fastapi + uvicorn)
+```
+echo-env:latest        500 MB  (python + fastapi + uvicorn + app)
+coding-env:latest      520 MB  (python + fastapi + uvicorn + app + tools)
+another-env:latest     510 MB  (python + fastapi + uvicorn + app)
+---
+Total: 1.5 GB (with lots of duplication)
+```
+
+### With Base Images (✅ Solution)
+```
+openenv-base:latest    300 MB  (python + fastapi + uvicorn)
+echo-env:latest         50 MB  (app only, uses base)
+coding-env:latest       70 MB  (app + tools, uses base)
+another-env:latest      45 MB  (app only, uses base)
+---
+Total: 465 MB (base shared, minimal duplication)
+```
+
+## Building the Base Image
+
+```bash
+# From project root
+docker build -t openenv-base:latest -f src/core/containers/images/Dockerfile .
+```
+
+## Usage in Environment Dockerfiles
+
+Each environment Dockerfile should start with:
+
+```dockerfile
+FROM openenv-base:latest
+
+# Copy only environment-specific files
+COPY src/core/ /app/src/core/
+COPY src/envs/my_env/ /app/src/envs/my_env/
+
+# Run the server
+CMD ["uvicorn", "envs.my_env.server.app:app", "--host", "0.0.0.0", "--port", "8000"]
+```
+
+## Base Image Contents
+
+- Python 3.11-slim
+- FastAPI >= 0.104.0
+- Uvicorn >= 0.24.0
+- Requests >= 2.25.0
+- curl (for health checks)
+
+## Example: Building Echo Environment
+
+```bash
+# Step 1: Build base image (do this once)
+docker build -t openenv-base:latest -f src/core/containers/images/Dockerfile .
+
+# Step 2: Build echo environment (uses base)
+docker build -t echo-env:latest -f src/envs/echo_env/server/Dockerfile .
+
+# Step 3: Run echo environment
+docker run -p 8000:8000 echo-env:latest
+```
+
+## Updating the Base
+
+When dependencies need updating:
+
+1. Update `src/core/containers/images/Dockerfile`
+2. Rebuild base image
+3. Rebuild all environment images (they'll use new base)
+
+```bash
+# Update base
+docker build -t openenv-base:latest -f src/core/containers/images/Dockerfile .
+
+# Rebuild environments (they automatically use new base)
+docker build -t echo-env:latest -f src/envs/echo_env/server/Dockerfile .
+```

src/core/containers/runtime/__init__.py

@@ -0,0 +1,15 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Container runtime providers."""
+
+from .providers import ContainerProvider, KubernetesProvider, LocalDockerProvider
+
+__all__ = [
+    "ContainerProvider",
+    "LocalDockerProvider",
+    "KubernetesProvider",
+]

src/core/containers/runtime/providers.py

@@ -0,0 +1,289 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+Container provider abstractions for running environment servers.
+
+This module provides a pluggable architecture for different container providers
+(local Docker, Kubernetes, cloud providers, etc.) to be used with HTTPEnvClient.
+"""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from typing import Any, Dict, Optional
+
+
+class ContainerProvider(ABC):
+    """
+    Abstract base class for container providers.
+
+    Providers implement this interface to support different container platforms:
+    - LocalDockerProvider: Runs containers on local Docker daemon
+    - KubernetesProvider: Runs containers in Kubernetes cluster
+    - FargateProvider: Runs containers on AWS Fargate
+    - CloudRunProvider: Runs containers on Google Cloud Run
+
+    The provider manages a single container lifecycle and provides the base URL
+    for connecting to it.
+
+    Example:
+        >>> provider = LocalDockerProvider()
+        >>> base_url = provider.start_container("echo-env:latest")
+        >>> print(base_url)  # http://localhost:8000
+        >>> # Use the environment via base_url
+        >>> provider.stop_container()
+    """
+
+    @abstractmethod
+    def start_container(
+        self,
+        image: str,
+        port: Optional[int] = None,
+        env_vars: Optional[Dict[str, str]] = None,
+        **kwargs: Any,
+    ) -> str:
+        """
+        Start a container from the specified image.
+
+        Args:
+            image: Container image name (e.g., "echo-env:latest")
+            port: Port to expose (if None, provider chooses)
+            env_vars: Environment variables to pass to container
+            **kwargs: Provider-specific options
+
+        Returns:
+            Base URL to connect to the container (e.g., "http://localhost:8000")
+
+        Raises:
+            RuntimeError: If container fails to start
+        """
+        pass
+
+    @abstractmethod
+    def stop_container(self) -> None:
+        """
+        Stop and remove the running container.
+
+        This cleans up the container that was started by start_container().
+        """
+        pass
+
+    @abstractmethod
+    def wait_for_ready(self, base_url: str, timeout_s: float = 30.0) -> None:
+        """
+        Wait for the container to be ready to accept requests.
+
+        This typically polls the /health endpoint until it returns 200.
+
+        Args:
+            base_url: Base URL of the container
+            timeout_s: Maximum time to wait
+
+        Raises:
+            TimeoutError: If container doesn't become ready in time
+        """
+        pass
+
+
+class LocalDockerProvider(ContainerProvider):
+    """
+    Container provider for local Docker daemon.
+
+    This provider runs containers on the local machine using Docker.
+    Useful for development and testing.
+
+    Example:
+        >>> provider = LocalDockerProvider()
+        >>> base_url = provider.start_container("echo-env:latest")
+        >>> # Container running on http://localhost:<random-port>
+        >>> provider.stop_container()
+    """
+
+    def __init__(self):
+        """Initialize the local Docker provider."""
+        self._container_id: Optional[str] = None
+        self._container_name: Optional[str] = None
+
+        # Check if Docker is available
+        import subprocess
+
+        try:
+            subprocess.run(
+                ["docker", "version"],
+                check=True,
+                capture_output=True,
+                timeout=5,
+            )
+        except (subprocess.CalledProcessError, FileNotFoundError, subprocess.TimeoutExpired):
+            raise RuntimeError(
+                "Docker is not available. Please install Docker Desktop or Docker Engine."
+            )
+
+    def start_container(
+        self,
+        image: str,
+        port: Optional[int] = None,
+        env_vars: Optional[Dict[str, str]] = None,
+        **kwargs: Any,
+    ) -> str:
+        """
+        Start a Docker container locally.
+
+        Args:
+            image: Docker image name
+            port: Port to expose (if None, finds available port)
+            env_vars: Environment variables for the container
+            **kwargs: Additional Docker run options
+
+        Returns:
+            Base URL to connect to the container
+        """
+        import subprocess
+        import time
+
+        # Find available port if not specified
+        if port is None:
+            port = self._find_available_port()
+
+        # Generate container name
+        self._container_name = self._generate_container_name(image)
+
+        # Build docker run command
+        cmd = [
+            "docker", "run",
+            "-d",  # Detached
+            "--name", self._container_name,
+            "-p", f"{port}:8000",  # Map port
+        ]
+
+        # Add environment variables
+        if env_vars:
+            for key, value in env_vars.items():
+                cmd.extend(["-e", f"{key}={value}"])
+
+        # Add image
+        cmd.append(image)
+
+        # Run container
+        result = subprocess.run(cmd, capture_output=True, text=True, check=True)
+        self._container_id = result.stdout.strip()
+
+        # Wait a moment for container to start
+        time.sleep(1)
+
+        base_url = f"http://localhost:{port}"
+        return base_url
+
+    def stop_container(self) -> None:
+        """
+        Stop and remove the Docker container.
+        """
+        if self._container_id is None:
+            return
+
+        import subprocess
+
+        try:
+            # Stop container
+            subprocess.run(
+                ["docker", "stop", self._container_id],
+                capture_output=True,
+                check=True,
+                timeout=10,
+            )
+
+            # Remove container
+            subprocess.run(
+                ["docker", "rm", self._container_id],
+                capture_output=True,
+                check=True,
+                timeout=10,
+            )
+        except subprocess.CalledProcessError:
+            # Container might already be stopped/removed
+            pass
+        finally:
+            self._container_id = None
+            self._container_name = None
+
+    def wait_for_ready(self, base_url: str, timeout_s: float = 30.0) -> None:
+        """
+        Wait for container to be ready by polling /health endpoint.
+
+        Args:
+            base_url: Base URL of the container
+            timeout_s: Maximum time to wait
+
+        Raises:
+            TimeoutError: If container doesn't become ready
+        """
+        import time
+        import requests
+
+        start_time = time.time()
+        health_url = f"{base_url}/health"
+
+        while time.time() - start_time < timeout_s:
+            try:
+                response = requests.get(health_url, timeout=2.0)
+                if response.status_code == 200:
+                    return
+            except requests.RequestException:
+                pass
+
+            time.sleep(0.5)
+
+        raise TimeoutError(
+            f"Container at {base_url} did not become ready within {timeout_s}s"
+        )
+
+    def _find_available_port(self) -> int:
+        """
+        Find an available port on localhost.
+
+        Returns:
+            An available port number
+        """
+        import socket
+
+        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+            s.bind(("", 0))
+            s.listen(1)
+            port = s.getsockname()[1]
+        return port
+
+    def _generate_container_name(self, image: str) -> str:
+        """
+        Generate a unique container name based on image name and timestamp.
+
+        Args:
+            image: Docker image name
+
+        Returns:
+            A unique container name
+        """
+        import time
+
+        clean_image = image.split("/")[-1].split(":")[0]
+        timestamp = int(time.time() * 1000)
+        return f"{clean_image}-{timestamp}"
+
+
+class KubernetesProvider(ContainerProvider):
+    """
+    Container provider for Kubernetes clusters.
+
+    This provider creates pods in a Kubernetes cluster and exposes them
+    via services or port-forwarding.
+
+    Example:
+        >>> provider = KubernetesProvider(namespace="envtorch-dev")
+        >>> base_url = provider.start_container("echo-env:latest")
+        >>> # Pod running in k8s, accessible via service or port-forward
+        >>> provider.stop_container()
+    """
+    pass

src/core/containers/test_local_docker_provider.py

@@ -0,0 +1,258 @@
+#!/usr/bin/env python3
+"""
+End-to-end test for LocalDockerProvider.
+
+This script tests the complete flow:
+1. Start a container using LocalDockerProvider
+2. Wait for it to be ready
+3. Make HTTP requests to test the environment
+4. Clean up the container
+"""
+
+import sys
+from pathlib import Path
+
+# Add src to path
+sys.path.insert(0, str(Path(__file__).parent.parent.parent))
+
+import requests
+
+from core.containers.runtime import LocalDockerProvider
+
+# TODO: Remove this test or make it a functional test sicne this will be tested in e2e test for echo env
+def test_local_docker_provider():
+    """Test LocalDockerProvider end-to-end."""
+    print("=" * 60)
+    print("LocalDockerProvider End-to-End Test")
+    print("=" * 60)
+    print()
+
+    provider = None
+
+    try:
+        # Step 1: Create provider
+        print("Step 1: Creating LocalDockerProvider...")
+        provider = LocalDockerProvider()
+        print("✓ Provider created\n")
+
+        # Step 2: Start container
+        print("Step 2: Starting echo-env container...")
+        base_url = provider.start_container("echo-env:latest")
+        print(f"✓ Container started at: {base_url}")
+        if provider._container_id:
+            print(f"  Container ID: {provider._container_id[:12]}...")
+        if provider._container_name:
+            print(f"  Container name: {provider._container_name}\n")
+
+        # Step 3: Wait for ready
+        print("Step 3: Waiting for container to be ready...")
+        provider.wait_for_ready(base_url, timeout_s=30.0)
+        print("✓ Container is ready!\n")
+
+        # Step 4: Test health endpoint
+        print("Step 4: Testing /health endpoint...")
+        response = requests.get(f"{base_url}/health")
+        print(f"  Status: {response.status_code}")
+        print(f"  Response: {response.json()}")
+        assert response.status_code == 200
+        assert response.json()["status"] == "healthy"
+        print("✓ Health check passed\n")
+
+        # Step 5: Test reset endpoint
+        print("Step 5: Testing /reset endpoint...")
+        response = requests.post(
+            f"{base_url}/reset",
+            json={},
+            headers={"Content-Type": "application/json"},
+        )
+        print(f"  Status: {response.status_code}")
+        data = response.json()
+        print(f"  Message: {data['observation']['echoed_message']}")
+        print(f"  Reward: {data['reward']}")
+        print(f"  Done: {data['done']}")
+        assert response.status_code == 200
+        assert data["observation"]["echoed_message"] == "Echo environment ready!"
+        print("✓ Reset test passed\n")
+
+        # Step 6: Test step endpoint
+        print("Step 6: Testing /step endpoint...")
+        response = requests.post(
+            f"{base_url}/step",
+            json={"action": {"message": "Hello from LocalDockerProvider!"}},
+            headers={"Content-Type": "application/json"},
+        )
+        print(f"  Status: {response.status_code}")
+        data = response.json()
+        print(f"  Echoed: {data['observation']['echoed_message']}")
+        print(f"  Length: {data['observation']['message_length']}")
+        print(f"  Reward: {data['reward']}")
+        assert response.status_code == 200
+        assert data["observation"]["echoed_message"] == "Hello from LocalDockerProvider!"
+        assert data["observation"]["message_length"] == 31
+        print("✓ Step test passed\n")
+
+        # Step 7: Test state endpoint
+        print("Step 7: Testing /state endpoint...")
+        response = requests.get(f"{base_url}/state")
+        print(f"  Status: {response.status_code}")
+        data = response.json()
+        print(f"  Episode ID: {data['episode_id']}")
+        print(f"  Step count: {data['step_count']}")
+        assert response.status_code == 200
+        assert data["step_count"] == 1  # One step from above
+        print("✓ State test passed\n")
+
+        # Step 8: Multiple steps
+        print("Step 8: Testing multiple steps...")
+        for i in range(3):
+            response = requests.post(
+                f"{base_url}/step",
+                json={"action": {"message": f"Message {i+1}"}},
+                headers={"Content-Type": "application/json"},
+            )
+            assert response.status_code == 200
+            print(f"  Step {i+1}: ✓")
+
+        # Check state updated
+        response = requests.get(f"{base_url}/state")
+        data = response.json()
+        assert data["step_count"] == 4  # 1 + 3 more steps
+        print(f"  Final step count: {data['step_count']}")
+        print("✓ Multiple steps test passed\n")
+
+        print("=" * 60)
+        print("✓ All tests passed!")
+        print("=" * 60)
+        print()
+
+        return True
+
+    except Exception as e:
+        print(f"\n❌ Test failed: {e}")
+        import traceback
+        traceback.print_exc()
+        return False
+
+    finally:
+        # Step 9: Cleanup
+        if provider is not None:
+            print("\nStep 9: Cleaning up container...")
+            try:
+                provider.stop_container()
+                print("✓ Container stopped and removed\n")
+            except Exception as e:
+                print(f"⚠️  Cleanup warning: {e}\n")
+
+
+def test_provider_with_custom_port():
+    """Test provider with custom port."""
+    print("=" * 60)
+    print("LocalDockerProvider with Custom Port Test")
+    print("=" * 60)
+    print()
+
+    provider = None
+
+    try:
+        provider = LocalDockerProvider()
+
+        print("Starting container on custom port 8123...")
+        base_url = provider.start_container("echo-env:latest", port=8123)
+        print(f"✓ Started at: {base_url}")
+        assert ":8123" in base_url
+
+        print("Waiting for ready...")
+        provider.wait_for_ready(base_url)
+        print("✓ Ready!")
+
+        print("Testing health...")
+        response = requests.get(f"{base_url}/health")
+        assert response.status_code == 200
+        print("✓ Health check passed")
+
+        print("\n✓ Custom port test passed!\n")
+        return True
+
+    except Exception as e:
+        print(f"\n❌ Test failed: {e}")
+        return False
+
+    finally:
+        if provider is not None:
+            provider.stop_container()
+            print("✓ Cleaned up\n")
+
+
+def test_provider_with_env_vars():
+    """Test provider with environment variables."""
+    print("=" * 60)
+    print("LocalDockerProvider with Environment Variables Test")
+    print("=" * 60)
+    print()
+
+    provider = None
+
+    try:
+        provider = LocalDockerProvider()
+
+        print("Starting container with environment variables...")
+        base_url = provider.start_container(
+            "echo-env:latest",
+            env_vars={"DEBUG": "true", "LOG_LEVEL": "info"}
+        )
+        print(f"✓ Started at: {base_url}")
+
+        print("Waiting for ready...")
+        provider.wait_for_ready(base_url)
+        print("✓ Ready!")
+
+        print("Testing health...")
+        response = requests.get(f"{base_url}/health")
+        assert response.status_code == 200
+        print("✓ Health check passed")
+
+        print("\n✓ Environment variables test passed!\n")
+        return True
+
+    except Exception as e:
+        print(f"\n❌ Test failed: {e}")
+        return False
+
+    finally:
+        if provider is not None:
+            provider.stop_container()
+            print("✓ Cleaned up\n")
+
+
+if __name__ == "__main__":
+    print()
+    print("🐳 LocalDockerProvider Test Suite")
+    print()
+
+    results = []
+
+    # Run basic test
+    results.append(("Basic End-to-End", test_local_docker_provider()))
+
+    # Run custom port test
+    results.append(("Custom Port", test_provider_with_custom_port()))
+
+    # Run environment variables test
+    results.append(("Environment Variables", test_provider_with_env_vars()))
+
+    # Summary
+    print("=" * 60)
+    print("Test Summary")
+    print("=" * 60)
+    for name, passed in results:
+        status = "✓ PASSED" if passed else "✗ FAILED"
+        print(f"{name:25} {status}")
+    print("=" * 60)
+
+    all_passed = all(result for _, result in results)
+    if all_passed:
+        print("\n🎉 All tests passed!")
+        exit(0)
+    else:
+        print("\n❌ Some tests failed")
+        exit(1)

src/core/env_server/__init__.py

@@ -0,0 +1,35 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Core environment interfaces and types."""
+
+from .base_transforms import CompositeTransform, NullTransform
+from .http_server import HTTPEnvServer, create_app, create_fastapi_app
+from .interfaces import Environment, Message, ModelTokenizer, Transform
+from .types import Action, Observation, State
+from .web_interface import create_web_interface_app, WebInterfaceManager
+
+__all__ = [
+    # Core interfaces
+    "Environment",
+    "Transform",
+    "Message",
+    "ModelTokenizer",
+    # Types
+    "Action",
+    "Observation",
+    "State",
+    # Base transforms
+    "CompositeTransform",
+    "NullTransform",
+    # HTTP Server
+    "HTTPEnvServer",
+    "create_app",
+    "create_fastapi_app",
+    # Web Interface
+    "create_web_interface_app",
+    "WebInterfaceManager",
+]

src/core/env_server/base_transforms.py

@@ -0,0 +1,29 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Base transform implementations for composing environment-specific transforms."""
+
+from .interfaces import Transform
+from .types import Observation
+
+
+class CompositeTransform(Transform):
+    """Combines multiple transforms into a single transform."""
+
+    def __init__(self, transforms: list[Transform]):
+        self.transforms = transforms
+
+    def __call__(self, observation: Observation) -> Observation:
+        for transform in self.transforms:
+            observation = transform(observation)
+        return observation
+
+
+class NullTransform(Transform):
+    """Default transform that passes through unchanged."""
+
+    def __call__(self, observation: Observation) -> Observation:
+        return observation

src/core/env_server/http_server.py

@@ -0,0 +1,233 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+HTTP server wrapper for Environment instances.
+
+This module provides utilities to wrap any Environment subclass and expose it
+over HTTP endpoints that HTTPEnvClient can consume.
+"""
+
+from __future__ import annotations
+
+import os
+from dataclasses import asdict
+from typing import Any, Dict, Type
+
+from .interfaces import Environment
+from .types import Action, Observation
+from fastapi import Body, FastAPI
+
+class HTTPEnvServer:
+    """
+    HTTP server wrapper for Environment instances.
+
+    This class wraps an Environment and exposes its reset(), step(), and state
+    methods as HTTP endpoints compatible with HTTPEnvClient.
+
+    The server expects:
+    - Action deserialization: Converts JSON dict to Action subclass
+    - Observation serialization: Converts Observation subclass to JSON dict
+
+    Example:
+        >>> from core.env_server import HTTPEnvServer
+        >>> from envs.coding_env.server import CodeExecutionEnvironment
+        >>>
+        >>> env = CodeExecutionEnvironment()
+        >>> server = HTTPEnvServer(env)
+        >>>
+        >>> # Register routes with FastAPI
+        >>> from fastapi import FastAPI
+        >>> app = FastAPI()
+        >>> server.register_routes(app)
+    """
+
+    def __init__(
+        self,
+        env: Environment,
+        action_cls: Type[Action],
+        observation_cls: Type[Observation],
+    ):
+        """
+        Initialize HTTP server wrapper.
+
+        Args:
+            env: The Environment instance to wrap
+            action_cls: The Action subclass this environment expects
+            observation_cls: The Observation subclass this environment returns
+        """
+        self.env = env
+        self.action_cls = action_cls
+        self.observation_cls = observation_cls
+
+    def register_routes(self, app: Any) -> None:
+        """
+        Register HTTP routes on a FastAPI application.
+
+        Args:
+            app: FastAPI application instance
+        """
+
+        if not isinstance(app, FastAPI):
+            raise TypeError("app must be a FastAPI instance")
+
+        @app.post("/reset")
+        async def reset(request: Dict[str, Any] = Body(default={})) -> Dict[str, Any]:
+            """Reset endpoint - returns initial observation."""
+            # TODO: Handle seed, episode_id from request if provided
+            observation = self.env.reset()
+            return self._serialize_observation(observation)
+
+        @app.post("/step")
+        async def step(request: Dict[str, Any]) -> Dict[str, Any]:
+            """Step endpoint - executes action and returns observation."""
+            action_data = request.get("action", {})
+            # TODO: Handle timeout_s, request_id, episode_id from request if provided
+
+            # Deserialize action
+            action = self._deserialize_action(action_data)
+
+            # Execute step
+            observation = self.env.step(action)
+
+            # Return serialized observation
+            return self._serialize_observation(observation)
+
+        @app.get("/state")
+        async def get_state() -> Dict[str, Any]:
+            """State endpoint - returns current environment state."""
+            state = self.env.state
+            return asdict(state)
+
+        @app.get("/health")
+        async def health() -> Dict[str, str]:
+            """Health check endpoint."""
+            return {"status": "healthy"}
+
+
+    def _deserialize_action(self, action_data: Dict[str, Any]) -> Action:
+        """
+        Convert JSON dict to Action instance.
+
+        Args:
+            action_data: Dictionary containing action data
+
+        Returns:
+            Action instance
+
+        Note:
+            This is a simple implementation. Subclasses may need to override
+            for more complex deserialization logic.
+        """
+        # Remove metadata if present (it will be set via kw_only field)
+        metadata = action_data.pop("metadata", {})
+        action = self.action_cls(**action_data)
+        action.metadata = metadata
+        return action
+
+    def _serialize_observation(self, observation: Observation) -> Dict[str, Any]:
+        """
+        Convert Observation instance to JSON-compatible dict.
+
+        Args:
+            observation: Observation instance
+
+        Returns:
+            Dictionary compatible with HTTPEnvClient._parse_result()
+
+        The format matches what HTTPEnvClient expects:
+        {
+            "observation": {...},  # Observation fields
+            "reward": float | None,
+            "done": bool,
+        }
+        """
+        obs_dict = asdict(observation)
+
+        # Extract reward and done (these are part of StepResult on client side)
+        reward = obs_dict.pop("reward", None)
+        done = obs_dict.pop("done", False)
+        obs_dict.pop("metadata", None)  # Remove metadata from observation
+
+        # Return in HTTPEnvClient expected format
+        return {
+            "observation": obs_dict,
+            "reward": reward,
+            "done": done,
+        }
+
+def create_app(
+    env: Environment,
+    action_cls: Type[Action],
+    observation_cls: Type[Observation],
+    env_name: Optional[str] = None,
+) -> Any:
+    """
+    Create a FastAPI application with or without web interface.
+    
+    This function creates a FastAPI app with the web interface enabled by default,
+    including README integration for better user experience.
+    
+    Args:
+        env: The Environment instance to serve
+        action_cls: The Action subclass this environment expects
+        observation_cls: The Observation subclass this environment returns
+        env_name: Optional environment name for README loading
+        
+    Returns:
+        FastAPI application instance with or without web interface and README integration
+    """
+    # Check if web interface should be enabled
+    # This can be controlled via environment variable or build argument
+    enable_web = (
+        os.getenv("ENABLE_WEB_INTERFACE", "false").lower() in ("true", "1", "yes")
+    )
+
+    if enable_web:
+        # Import web interface only when needed
+        from .web_interface import create_web_interface_app
+        return create_web_interface_app(env, action_cls, observation_cls, env_name)
+    else:
+        # Use standard FastAPI app without web interface
+        return create_fastapi_app(env, action_cls, observation_cls)
+    
+
+def create_fastapi_app(
+    env: Environment,
+    action_cls: Type[Action],
+    observation_cls: Type[Observation],
+) -> Any:
+    """
+    Create a FastAPI application with routes for the given environment.
+
+    Args:
+        env: The Environment instance to serve
+        action_cls: The Action subclass this environment expects
+        observation_cls: The Observation subclass this environment returns
+
+    Returns:
+        FastAPI application instance with routes registered
+
+    Example:
+        >>> from envs.coding_env.server import CodeExecutionEnvironment
+        >>> from envs.coding_env.models import CodeAction, CodeObservation
+        >>>
+        >>> env = CodeExecutionEnvironment()
+        >>> app = create_fastapi_app(env, CodeAction, CodeObservation)
+        >>>
+        >>> # Run with: uvicorn module:app --host 0.0.0.0 --port 8000
+    """
+    try:
+        from fastapi import FastAPI
+    except ImportError:
+        raise ImportError(
+            "FastAPI is required. Install with: pip install fastapi uvicorn"
+        )
+
+    app = FastAPI(title="Environment HTTP Server")
+    server = HTTPEnvServer(env, action_cls, observation_cls)
+    server.register_routes(app)
+    return app

src/core/env_server/interfaces.py

@@ -0,0 +1,118 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+from abc import ABC, abstractmethod
+from typing import Any, Protocol, TypedDict
+
+from .types import Action, Observation, State
+
+
+class Message(TypedDict):
+    """A message in a conversation.
+
+    Compatible with Huggingface chat template format.
+    """
+
+    role: str
+    content: str
+
+
+class ModelTokenizer(Protocol):
+    """Protocol for tokenizers that support chat templates.
+
+    This protocol defines the interface that tokenizers must implement
+    to work with chat-based environments. It's compatible with
+    Huggingface transformers tokenizers.
+    """
+
+    def apply_chat_template(
+        self,
+        conversation: list[Message],
+        tokenize: bool = True,
+        return_tensors: str | None = None,
+        **kwargs: Any,
+    ) -> Any:
+        """Apply a chat template to format and optionally tokenize a conversation.
+
+        Args:
+            conversation: List of message dictionaries with 'role' and 'content'
+            tokenize: Whether to tokenize the output
+            return_tensors: Format for returned tensors ('pt' for PyTorch)
+            **kwargs: Additional arguments
+
+        Returns:
+            Formatted and optionally tokenized conversation
+        """
+        ...
+
+    def decode(
+        self, token_ids: Any, skip_special_tokens: bool = False, **kwargs: Any
+    ) -> str:
+        """Decode token IDs back to text.
+
+        Args:
+            token_ids: Token IDs to decode
+            skip_special_tokens: Whether to skip special tokens in output
+            **kwargs: Additional arguments
+
+        Returns:
+            Decoded text string
+        """
+        ...
+
+
+class Transform(ABC):
+    """Transform observations to add rewards, metrics, or other modifications.
+
+    Transforms follow the TorchRL pattern where they take an observation
+    and return a (potentially modified) observation. This allows for
+    flexible reward computation and observation augmentation.
+    """
+
+    @abstractmethod
+    def __call__(self, observation: Observation) -> Observation:
+        """Transform an observation.
+
+        Args:
+            observation: The input observation
+
+        Returns:
+            The transformed observation
+        """
+        pass
+
+
+class Environment(ABC):
+    """Base class for all environment servers following Gym/Gymnasium API.
+
+    Args:
+        transform: Optional transform to apply to observations
+    """
+
+    def __init__(self, transform: Transform | None = None):
+        self.transform = transform
+
+    @abstractmethod
+    def reset(self) -> Observation:
+        """Reset the environment and return initial observation."""
+        pass
+
+    @abstractmethod
+    def step(self, action: Action) -> Observation:
+        """Take a step in the environment."""
+        pass
+
+    @property
+    @abstractmethod
+    def state(self) -> State:
+        """Get the current environment state."""
+        pass
+
+    def _apply_transform(self, observation: Observation) -> Observation:
+        """Apply transform if one is provided."""
+        if self.transform is not None:
+            return self.transform(observation)
+        return observation

src/core/env_server/types.py

@@ -0,0 +1,57 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+from dataclasses import dataclass, field
+from typing import Any, Dict, List, Optional, Union
+
+
+# Type aliases
+Scalar = Union[int, float, bool]
+
+
+@dataclass(kw_only=True)
+class Action:
+    """Base class for all environment actions."""
+
+    metadata: Dict[str, Any] = field(default_factory=dict)
+
+
+@dataclass(kw_only=True)
+class Observation:
+    """Base class for all environment observations."""
+
+    done: bool = False
+    reward: Union[bool, int, float, None] = None
+    metadata: Dict[str, Any] = field(default_factory=dict)
+
+
+@dataclass
+class State:
+    """Base class for environment state."""
+
+    episode_id: Optional[str] = None
+    step_count: int = 0
+
+
+@dataclass
+class CodeExecResult:
+    """Result of code execution containing stdout, stderr, and exit code."""
+
+    stdout: str
+    stderr: str
+    exit_code: int
+
+
+@dataclass
+class EnvironmentMetadata:
+    """Metadata about an environment for documentation and UI purposes."""
+    
+    name: str
+    description: str
+    readme_content: Optional[str] = None
+    version: Optional[str] = None
+    author: Optional[str] = None
+    documentation_url: Optional[str] = None

src/core/env_server/web_interface.py

@@ -0,0 +1,1613 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+Web interface for OpenEnv environments.
+
+This module provides a web-based interface for interacting with OpenEnv environments,
+including a two-pane layout for HumanAgent interaction and state observation.
+"""
+
+from __future__ import annotations
+
+import json
+import time
+from dataclasses import asdict, dataclass
+from typing import Any, Dict, List, Optional, Type
+from datetime import datetime
+
+from fastapi import FastAPI, WebSocket, WebSocketDisconnect, Request
+from fastapi.responses import HTMLResponse, FileResponse
+from fastapi.staticfiles import StaticFiles
+from pydantic import BaseModel
+
+from .interfaces import Environment
+from .types import Action, Observation, State, EnvironmentMetadata
+
+
+def load_environment_metadata(env: Environment, env_name: Optional[str] = None) -> EnvironmentMetadata:
+    """
+    Load environment metadata including README content.
+    
+    Args:
+        env: The environment instance
+        env_name: Optional environment name for README file lookup
+        
+    Returns:
+        EnvironmentMetadata with loaded information
+    """
+    # Try to get metadata from environment if it has a method for it
+    if hasattr(env, 'get_metadata'):
+        return env.get_metadata()
+    
+    # Default metadata
+    metadata = EnvironmentMetadata(
+        name=env_name or env.__class__.__name__,
+        description=f"{env.__class__.__name__} environment",
+        version="1.0.0"
+    )
+    
+    # Try to load README from file system
+    readme_content = _load_readme_from_filesystem(env_name)
+    if readme_content:
+        metadata.readme_content = readme_content
+    
+    return metadata
+
+
+def _load_readme_from_filesystem(env_name: Optional[str]) -> Optional[str]:
+    """
+    Load README content from the filesystem.
+    
+    Tries multiple locations:
+    1. Container filesystem: /app/README.md
+    2. Local development: src/envs/{env_name}/README.md
+    3. Environment variable: ENV_README_PATH
+    """
+    import os
+    from pathlib import Path
+    
+    # Try container filesystem first
+    container_readme = Path("/app/README.md")
+    if container_readme.exists():
+        try:
+            return container_readme.read_text(encoding='utf-8')
+        except Exception:
+            pass
+    
+    # Try environment variable path
+    custom_path = os.environ.get("ENV_README_PATH")
+    if custom_path and Path(custom_path).exists():
+        try:
+            return Path(custom_path).read_text(encoding='utf-8')
+        except Exception:
+            pass
+    
+    # Try local development path
+    if env_name:
+        local_readme = Path(f"src/envs/{env_name}/README.md")
+        if local_readme.exists():
+            try:
+                return local_readme.read_text(encoding='utf-8')
+            except Exception:
+                pass
+    
+    return None
+
+
+@dataclass
+class ActionLog:
+    """Log entry for an action taken."""
+    timestamp: str
+    action: Dict[str, Any]
+    observation: Dict[str, Any]
+    reward: Optional[float]
+    done: bool
+    step_count: int
+
+
+@dataclass
+class EpisodeState:
+    """Current episode state for the web interface."""
+    episode_id: Optional[str]
+    step_count: int
+    current_observation: Optional[Dict[str, Any]]
+    action_logs: List[ActionLog]
+    is_reset: bool = True
+
+
+class WebInterfaceManager:
+    """Manages the web interface for an environment."""
+    
+    def __init__(
+        self,
+        env: Environment,
+        action_cls: Type[Action],
+        observation_cls: Type[Observation],
+        metadata: Optional[EnvironmentMetadata] = None,
+    ):
+        self.env = env
+        self.action_cls = action_cls
+        self.observation_cls = observation_cls
+        self.metadata = metadata or EnvironmentMetadata(
+            name=env.__class__.__name__,
+            description=f"{env.__class__.__name__} environment"
+        )
+        self.episode_state = EpisodeState(
+            episode_id=None,
+            step_count=0,
+            current_observation=None,
+            action_logs=[]
+        )
+        self.connected_clients: List[WebSocket] = []
+    
+    async def connect_websocket(self, websocket: WebSocket):
+        """Connect a new WebSocket client."""
+        await websocket.accept()
+        self.connected_clients.append(websocket)
+        
+        # Send current state to the new client
+        await self._send_state_update()
+    
+    async def disconnect_websocket(self, websocket: WebSocket):
+        """Disconnect a WebSocket client."""
+        if websocket in self.connected_clients:
+            self.connected_clients.remove(websocket)
+    
+    async def _send_state_update(self):
+        """Send current state to all connected clients."""
+        if not self.connected_clients:
+            return
+            
+        state_data = {
+            "type": "state_update",
+            "episode_state": asdict(self.episode_state)
+        }
+        
+        # Send to all connected clients
+        disconnected_clients = []
+        for client in self.connected_clients:
+            try:
+                await client.send_text(json.dumps(state_data))
+            except:
+                disconnected_clients.append(client)
+        
+        # Remove disconnected clients
+        for client in disconnected_clients:
+            self.connected_clients.remove(client)
+    
+    async def reset_environment(self) -> Dict[str, Any]:
+        """Reset the environment and update state."""
+        observation = self.env.reset()
+        state = self.env.state
+        
+        # Update episode state
+        self.episode_state.episode_id = state.episode_id
+        self.episode_state.step_count = 0
+        self.episode_state.current_observation = asdict(observation)
+        self.episode_state.action_logs = []
+        self.episode_state.is_reset = True
+        
+        # Send state update
+        await self._send_state_update()
+        
+        return {
+            "observation": asdict(observation),
+            "reward": observation.reward,
+            "done": observation.done,
+        }
+    
+    async def step_environment(self, action_data: Dict[str, Any]) -> Dict[str, Any]:
+        """Execute a step in the environment and update state."""
+        # Deserialize action
+        action = self._deserialize_action(action_data)
+        
+        # Execute step
+        observation = self.env.step(action)
+        state = self.env.state
+        
+        # Create action log
+        action_log = ActionLog(
+            timestamp=datetime.now().isoformat(),
+            action=asdict(action),
+            observation=asdict(observation),
+            reward=observation.reward,
+            done=observation.done,
+            step_count=state.step_count
+        )
+        
+        # Update episode state
+        self.episode_state.episode_id = state.episode_id
+        self.episode_state.step_count = state.step_count
+        self.episode_state.current_observation = asdict(observation)
+        self.episode_state.action_logs.append(action_log)
+        self.episode_state.is_reset = False
+        
+        # Send state update
+        await self._send_state_update()
+        
+        return {
+            "observation": asdict(observation),
+            "reward": observation.reward,
+            "done": observation.done,
+        }
+    
+    def get_state(self) -> Dict[str, Any]:
+        """Get current environment state."""
+        state = self.env.state
+        return asdict(state)
+    
+    def _deserialize_action(self, action_data: Dict[str, Any]) -> Action:
+        """Convert JSON dict to Action instance."""
+        metadata = action_data.pop("metadata", {})
+        
+        # Handle tensor fields that come from JSON as lists
+        processed_data = {}
+        for key, value in action_data.items():
+            if key == "tokens" and isinstance(value, (list, str)):
+                # Convert list or string to tensor
+                if isinstance(value, str):
+                    # If it's a string, try to parse it as a list of numbers
+                    try:
+                        import json
+                        value = json.loads(value)
+                    except:
+                        # If parsing fails, treat as empty list
+                        value = []
+                if isinstance(value, list):
+                    import torch
+                    processed_data[key] = torch.tensor(value, dtype=torch.long)
+                else:
+                    processed_data[key] = value
+            elif key == "action_id" and isinstance(value, str):
+                # Convert action_id from string to int
+                try:
+                    processed_data[key] = int(value)
+                except ValueError:
+                    # If conversion fails, keep original value
+                    processed_data[key] = value
+            else:
+                processed_data[key] = value
+        
+        action = self.action_cls(**processed_data)
+        action.metadata = metadata
+        return action
+
+
+def create_web_interface_app(
+    env: Environment,
+    action_cls: Type[Action],
+    observation_cls: Type[Observation],
+    env_name: Optional[str] = None,
+) -> FastAPI:
+    """
+    Create a FastAPI application with web interface for the given environment.
+    
+    Args:
+        env: The Environment instance to serve
+        action_cls: The Action subclass this environment expects
+        observation_cls: The Observation subclass this environment returns
+        env_name: Optional environment name for README loading
+        
+    Returns:
+        FastAPI application instance with web interface
+    """
+    from .http_server import create_fastapi_app
+    
+    # Create the base environment app
+    app = create_fastapi_app(env, action_cls, observation_cls)
+    
+    # Load environment metadata
+    metadata = load_environment_metadata(env, env_name)
+    
+    # Create web interface manager
+    web_manager = WebInterfaceManager(env, action_cls, observation_cls, metadata)
+    
+    # Add web interface routes
+    @app.get("/web", response_class=HTMLResponse)
+    async def web_interface():
+        """Serve the web interface."""
+        return get_web_interface_html(action_cls, web_manager.metadata)
+    
+    @app.get("/web/metadata")
+    async def web_metadata():
+        """Get environment metadata."""
+        return asdict(web_manager.metadata)
+    
+    @app.websocket("/ws")
+    async def websocket_endpoint(websocket: WebSocket):
+        """WebSocket endpoint for real-time updates."""
+        await web_manager.connect_websocket(websocket)
+        try:
+            while True:
+                # Keep connection alive
+                await websocket.receive_text()
+        except WebSocketDisconnect:
+            await web_manager.disconnect_websocket(websocket)
+    
+    @app.post("/web/reset")
+    async def web_reset():
+        """Reset endpoint for web interface."""
+        return await web_manager.reset_environment()
+    
+    @app.post("/web/step")
+    async def web_step(request: Dict[str, Any]):
+        """Step endpoint for web interface."""
+        # Check if this is a message-based request (chat environment)
+        if "message" in request:
+            message = request["message"]
+            # Convert message to action using the environment's message_to_action method
+            action = web_manager.env.message_to_action(message)
+            action_data = {"tokens": action.tokens.tolist()}
+        else:
+            action_data = request.get("action", {})
+        
+        return await web_manager.step_environment(action_data)
+    
+    @app.get("/web/state")
+    async def web_state():
+        """State endpoint for web interface."""
+        return web_manager.get_state()
+    
+    return app
+
+
+def get_web_interface_html(action_cls: Type[Action], metadata: Optional[EnvironmentMetadata] = None) -> str:
+    """Generate the HTML for the web interface."""
+    
+    # Check if this is a chat environment by looking for tokens field
+    is_chat_env = False
+    if hasattr(action_cls, '__dataclass_fields__'):
+        for field_name, field_info in action_cls.__dataclass_fields__.items():
+            if field_name == 'tokens' and hasattr(field_info.type, '__name__') and 'Tensor' in field_info.type.__name__:
+                is_chat_env = True
+                break
+    
+    # Get action fields for dynamic form generation with enhanced metadata
+    action_fields = _extract_action_fields(action_cls)
+    
+    return f"""
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>OpenEnv Web Interface</title>
+    <style>
+        * {{
+            margin: 0;
+            padding: 0;
+            box-sizing: border-box;
+        }}
+        
+        body {{
+            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+            background-color: #f5f5f5;
+            height: 100vh;
+            overflow: hidden;
+        }}
+        
+        .container {{
+            display: flex;
+            height: 100vh;
+        }}
+        
+        .left-pane {{
+            width: 50%;
+            background: white;
+            border-right: 1px solid #e0e0e0;
+            display: flex;
+            flex-direction: column;
+        }}
+        
+        .right-pane {{
+            width: 50%;
+            background: #fafafa;
+            display: flex;
+            flex-direction: column;
+        }}
+        
+        .pane-header {{
+            padding: 20px;
+            border-bottom: 1px solid #e0e0e0;
+            background: #f8f9fa;
+            font-weight: 600;
+            font-size: 16px;
+        }}
+        
+        .pane-content {{
+            flex: 1;
+            padding: 20px;
+            overflow-y: auto;
+        }}
+        
+        .action-form {{
+            background: white;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 20px;
+            margin-bottom: 20px;
+        }}
+        
+        .form-group {{
+            margin-bottom: 15px;
+        }}
+        
+        .form-group label {{
+            display: block;
+            margin-bottom: 5px;
+            font-weight: 500;
+            color: #333;
+        }}
+        
+        .form-group input, .form-group textarea {{
+            width: 100%;
+            padding: 8px 12px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+            font-size: 14px;
+        }}
+        
+        .form-group input:focus, .form-group textarea:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        .btn {{
+            background: #007bff;
+            color: white;
+            border: none;
+            padding: 10px 20px;
+            border-radius: 4px;
+            cursor: pointer;
+            font-size: 14px;
+            margin-right: 10px;
+            margin-bottom: 10px;
+        }}
+        
+        .btn:hover {{
+            background: #0056b3;
+        }}
+        
+        .btn:disabled {{
+            background: #6c757d;
+            cursor: not-allowed;
+        }}
+        
+        .btn-secondary {{
+            background: #6c757d;
+        }}
+        
+        .btn-secondary:hover {{
+            background: #545b62;
+        }}
+        
+        .state-display {{
+            background: white;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 15px;
+            margin-bottom: 20px;
+        }}
+        
+        .state-item {{
+            margin-bottom: 8px;
+        }}
+        
+        .state-label {{
+            font-weight: 500;
+            color: #666;
+        }}
+        
+        .state-value {{
+            color: #333;
+            font-family: monospace;
+        }}
+        
+        .logs-container {{
+            background: white;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 15px;
+            max-height: 400px;
+            overflow-y: auto;
+        }}
+        
+        .log-entry {{
+            border-bottom: 1px solid #f0f0f0;
+            padding: 10px 0;
+        }}
+        
+        .log-entry:last-child {{
+            border-bottom: none;
+        }}
+        
+        .log-timestamp {{
+            font-size: 12px;
+            color: #666;
+            margin-bottom: 5px;
+        }}
+        
+        .log-action {{
+            background: #e3f2fd;
+            padding: 8px;
+            border-radius: 4px;
+            margin-bottom: 5px;
+            font-family: monospace;
+            font-size: 12px;
+        }}
+        
+        .log-observation {{
+            background: #f3e5f5;
+            padding: 8px;
+            border-radius: 4px;
+            font-family: monospace;
+            font-size: 12px;
+        }}
+        
+        .log-reward {{
+            font-weight: 600;
+            color: #28a745;
+        }}
+        
+        .log-done {{
+            font-weight: 600;
+            color: #dc3545;
+        }}
+        
+        .status-indicator {{
+            display: inline-block;
+            width: 8px;
+            height: 8px;
+            border-radius: 50%;
+            margin-right: 8px;
+        }}
+        
+        .status-connected {{
+            background: #28a745;
+        }}
+        
+        .status-disconnected {{
+            background: #dc3545;
+        }}
+        
+        .json-display {{
+            background: #f8f9fa;
+            border: 1px solid #e9ecef;
+            border-radius: 4px;
+            padding: 10px;
+            font-family: monospace;
+            font-size: 12px;
+            white-space: pre-wrap;
+            max-height: 200px;
+            overflow-y: auto;
+        }}
+        
+        /* Chat Interface Styles */
+        .chat-interface {{
+            background: white;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 20px;
+            margin-bottom: 20px;
+        }}
+        
+        .chat-messages {{
+            background: #f8f9fa;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 15px;
+            margin-bottom: 15px;
+            max-height: 400px;
+            overflow-y: auto;
+        }}
+        
+        .chat-message {{
+            margin-bottom: 15px;
+            padding: 10px;
+            border-radius: 8px;
+        }}
+        
+        .chat-message:last-child {{
+            margin-bottom: 0;
+        }}
+        
+        .chat-message.user {{
+            background: #e3f2fd;
+            margin-left: 20px;
+        }}
+        
+        .chat-message.assistant {{
+            background: #f3e5f5;
+            margin-right: 20px;
+        }}
+        
+        .chat-message.system {{
+            background: #e8f5e8;
+            font-style: italic;
+        }}
+        
+        .message-role {{
+            font-weight: 600;
+            font-size: 12px;
+            color: #666;
+            margin-bottom: 5px;
+        }}
+        
+        .message-content {{
+            font-size: 14px;
+            line-height: 1.4;
+        }}
+        
+        .chat-input-container {{
+            border-top: 1px solid #e0e0e0;
+            padding-top: 15px;
+        }}
+        
+        .role-selector {{
+            margin-bottom: 10px;
+        }}
+        
+        .role-selector label {{
+            font-weight: 500;
+            margin-right: 10px;
+        }}
+        
+        .role-selector select {{
+            padding: 5px 10px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+        }}
+        
+        .message-input {{
+            display: flex;
+            gap: 10px;
+            align-items: flex-end;
+        }}
+        
+        .message-input textarea {{
+            flex: 1;
+            padding: 10px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+            resize: vertical;
+            font-family: inherit;
+        }}
+        
+        .message-input textarea:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        /* Instructions Section Styles */
+        .instructions-section {{
+            background: white;
+            border: 1px solid #e0e0e0;
+            border-radius: 8px;
+            padding: 20px;
+            margin-bottom: 20px;
+        }}
+        
+        .instructions-header {{
+            display: flex;
+            justify-content: space-between;
+            align-items: center;
+            margin-bottom: 15px;
+        }}
+        
+        .instructions-title {{
+            font-size: 18px;
+            font-weight: 600;
+            color: #333;
+            margin: 0;
+        }}
+        
+        .instructions-toggle {{
+            background: #f8f9fa;
+            border: 1px solid #dee2e6;
+            border-radius: 4px;
+            padding: 5px 10px;
+            cursor: pointer;
+            font-size: 12px;
+            color: #6c757d;
+        }}
+        
+        .instructions-toggle:hover {{
+            background: #e9ecef;
+        }}
+        
+        .instructions-content {{
+            display: none;
+            max-height: 400px;
+            overflow-y: auto;
+            border-top: 1px solid #e0e0e0;
+            padding-top: 15px;
+        }}
+        
+        .instructions-content.expanded {{
+            display: block;
+        }}
+        
+        .instructions-content h1,
+        .instructions-content h2,
+        .instructions-content h3 {{
+            color: #333;
+            margin-top: 20px;
+            margin-bottom: 10px;
+        }}
+        
+        .instructions-content h1 {{
+            font-size: 24px;
+            border-bottom: 2px solid #007bff;
+            padding-bottom: 10px;
+        }}
+        
+        .instructions-content h2 {{
+            font-size: 20px;
+        }}
+        
+        .instructions-content h3 {{
+            font-size: 16px;
+        }}
+        
+        .instructions-content p {{
+            margin-bottom: 10px;
+            line-height: 1.6;
+        }}
+        
+        .instructions-content code {{
+            background: #f8f9fa;
+            padding: 2px 4px;
+            border-radius: 3px;
+            font-family: monospace;
+            font-size: 14px;
+        }}
+        
+        .instructions-content pre {{
+            background: #f8f9fa;
+            border: 1px solid #e9ecef;
+            border-radius: 4px;
+            padding: 15px;
+            overflow-x: auto;
+            margin: 10px 0;
+        }}
+        
+        .instructions-content pre code {{
+            background: none;
+            padding: 0;
+        }}
+        
+        .instructions-content ul,
+        .instructions-content ol {{
+            margin: 10px 0;
+            padding-left: 20px;
+        }}
+        
+        .instructions-content li {{
+            margin-bottom: 5px;
+        }}
+        
+        .instructions-content table {{
+            border-collapse: collapse;
+            width: 100%;
+            margin: 15px 0;
+        }}
+        
+        .instructions-content th,
+        .instructions-content td {{
+            border: 1px solid #dee2e6;
+            padding: 8px 12px;
+            text-align: left;
+        }}
+        
+        .instructions-content th {{
+            background: #f8f9fa;
+            font-weight: 600;
+        }}
+        
+        /* Enhanced Form Styles */
+        .help-text {{
+            display: block;
+            margin-top: 5px;
+            font-size: 12px;
+            color: #6c757d;
+            font-style: italic;
+        }}
+        
+        .form-group label {{
+            font-weight: 500;
+            color: #333;
+            margin-bottom: 5px;
+        }}
+        
+        .form-group select {{
+            width: 100%;
+            padding: 8px 12px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+            font-size: 14px;
+            background-color: white;
+        }}
+        
+        .form-group select:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        .form-group textarea {{
+            width: 100%;
+            padding: 8px 12px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+            font-size: 14px;
+            font-family: inherit;
+            resize: vertical;
+        }}
+        
+        .form-group textarea:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        .form-group input[type="number"] {{
+            width: 100%;
+            padding: 8px 12px;
+            border: 1px solid #ddd;
+            border-radius: 4px;
+            font-size: 14px;
+        }}
+        
+        .form-group input[type="number"]:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        .form-group input[type="text"]:focus {{
+            outline: none;
+            border-color: #007bff;
+            box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
+        }}
+        
+        .required-indicator {{
+            color: #dc3545;
+            font-weight: bold;
+        }}
+        
+        .form-group .field-description {{
+            font-size: 11px;
+            color: #666;
+            margin-top: 2px;
+            font-style: italic;
+        }}
+    </style>
+</head>
+<body>
+    <div class="container">
+        <!-- Left Pane: HumanAgent Interface -->
+        <div class="left-pane">
+            <div class="pane-header">
+                <span class="status-indicator status-disconnected" id="connection-status"></span>
+                HumanAgent Interface
+            </div>
+            <div class="pane-content">
+                <!-- Instructions Section -->
+                {_generate_instructions_section(metadata)}
+                
+                <!-- Action Form or Chat Interface -->
+                {_generate_action_interface(action_fields, is_chat_env)}
+                
+                <!-- Control Buttons -->
+                <div style="margin-bottom: 20px;">
+                    <button class="btn btn-secondary" id="reset-btn">Reset Environment</button>
+                    <button class="btn btn-secondary" id="state-btn">Get State</button>
+                </div>
+                
+                <!-- Current State Display -->
+                <div class="state-display">
+                    <h3>Current State</h3>
+                    <div id="current-state">
+                        <div class="state-item">
+                            <span class="state-label">Status:</span>
+                            <span class="state-value" id="env-status">Not initialized</span>
+                        </div>
+                        <div class="state-item">
+                            <span class="state-label">Episode ID:</span>
+                            <span class="state-value" id="episode-id">-</span>
+                        </div>
+                        <div class="state-item">
+                            <span class="state-label">Step Count:</span>
+                            <span class="state-value" id="step-count">0</span>
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
+        
+        <!-- Right Pane: State Observer -->
+        <div class="right-pane">
+            <div class="pane-header">
+                State Observer
+            </div>
+            <div class="pane-content">
+                <!-- Current Observation -->
+                <div class="state-display">
+                    <h3>Current Observation</h3>
+                    <div id="current-observation" class="json-display">
+                        No observation yet
+                    </div>
+                </div>
+                
+                <!-- Action Logs -->
+                <div class="logs-container">
+                    <h3>Action History</h3>
+                    <div id="action-logs">
+                        No actions taken yet
+                    </div>
+                </div>
+            </div>
+        </div>
+    </div>
+
+    <script>
+        class OpenEnvWebInterface {{
+            constructor() {{
+                this.ws = null;
+                this.isConnected = false;
+                this.init();
+            }}
+            
+            init() {{
+                this.connectWebSocket();
+                this.setupEventListeners();
+            }}
+            
+            connectWebSocket() {{
+                const protocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
+                const wsUrl = `${{protocol}}//${{window.location.host}}/ws`;
+                
+                this.ws = new WebSocket(wsUrl);
+                
+                this.ws.onopen = () => {{
+                    this.isConnected = true;
+                    this.updateConnectionStatus(true);
+                    console.log('WebSocket connected');
+                }};
+                
+                this.ws.onmessage = (event) => {{
+                    const data = JSON.parse(event.data);
+                    if (data.type === 'state_update') {{
+                        this.updateUI(data.episode_state);
+                    }}
+                }};
+                
+                this.ws.onclose = () => {{
+                    this.isConnected = false;
+                    this.updateConnectionStatus(false);
+                    console.log('WebSocket disconnected');
+                    // Attempt to reconnect after 3 seconds
+                    setTimeout(() => this.connectWebSocket(), 3000);
+                }};
+                
+                this.ws.onerror = (error) => {{
+                    console.error('WebSocket error:', error);
+                }};
+            }}
+            
+            setupEventListeners() {{
+                // Instructions toggle
+                const instructionsToggle = document.getElementById('instructions-toggle');
+                const instructionsContent = document.getElementById('instructions-content');
+                if (instructionsToggle && instructionsContent) {{
+                    instructionsToggle.addEventListener('click', () => {{
+                        instructionsContent.classList.toggle('expanded');
+                        instructionsToggle.textContent = instructionsContent.classList.contains('expanded') 
+                            ? 'Hide Instructions' : 'Show Instructions';
+                    }});
+                }}
+                
+                // Check if this is a chat environment
+                const isChatEnv = document.getElementById('chat-messages') !== null;
+                
+                if (isChatEnv) {{
+                    // Chat environment event listeners
+                    document.getElementById('send-message-btn').addEventListener('click', () => {{
+                        this.sendMessage();
+                    }});
+                    
+                    // Send message on Enter (but allow Shift+Enter for new lines)
+                    document.getElementById('message-input').addEventListener('keydown', (e) => {{
+                        if (e.key === 'Enter' && !e.shiftKey) {{
+                            e.preventDefault();
+                            this.sendMessage();
+                        }}
+                    }});
+                }} else {{
+                    // Traditional action form submission
+                    const actionForm = document.getElementById('action-form');
+                    if (actionForm) {{
+                        actionForm.addEventListener('submit', (e) => {{
+                            e.preventDefault();
+                            this.submitAction();
+                        }});
+                    }}
+                }}
+                
+                // Reset button
+                document.getElementById('reset-btn').addEventListener('click', () => {{
+                    this.resetEnvironment();
+                }});
+                
+                // State button
+                document.getElementById('state-btn').addEventListener('click', () => {{
+                    this.getState();
+                }});
+            }}
+            
+            async sendMessage() {{
+                const messageInput = document.getElementById('message-input');
+                const roleSelect = document.getElementById('message-role');
+                const message = messageInput.value.trim();
+                const role = roleSelect.value;
+                
+                if (!message) {{
+                    return;
+                }}
+                
+                // Add message to chat display immediately
+                this.addMessageToChat(role, message);
+                
+                // Clear input
+                messageInput.value = '';
+                
+                try {{
+                    // Send message to server to convert to action and step
+                    const response = await fetch('/web/step', {{
+                        method: 'POST',
+                        headers: {{ 'Content-Type': 'application/json' }},
+                        body: JSON.stringify({{ 
+                            message: {{
+                                role: role,
+                                content: message
+                            }}
+                        }})
+                    }});
+                    
+                    if (!response.ok) {{
+                        throw new Error(`HTTP error! status: ${{response.status}}`);
+                    }}
+                    
+                    const result = await response.json();
+                    console.log('Message sent:', result);
+                }} catch (error) {{
+                    console.error('Error sending message:', error);
+                    alert('Error sending message: ' + error.message);
+                }}
+            }}
+            
+            addMessageToChat(role, content) {{
+                const chatMessages = document.getElementById('chat-messages');
+                const messageDiv = document.createElement('div');
+                messageDiv.className = `chat-message ${{role}}`;
+                
+                messageDiv.innerHTML = `
+                    <div class="message-role">${{role.charAt(0).toUpperCase() + role.slice(1)}}</div>
+                    <div class="message-content">${{content}}</div>
+                `;
+                
+                chatMessages.appendChild(messageDiv);
+                chatMessages.scrollTop = chatMessages.scrollHeight;
+            }}
+            
+            async submitAction() {{
+                const formData = new FormData(document.getElementById('action-form'));
+                const action = {{}};
+                
+                // Collect form data
+                for (const [key, value] of formData.entries()) {{
+                    if (value !== '') {{
+                        // Handle tensor fields (tokens) - convert comma-separated string to array
+                        if (key === 'tokens') {{
+                            try {{
+                                action[key] = value.split(',').map(x => parseInt(x.trim())).filter(x => !isNaN(x));
+                            }} catch (e) {{
+                                console.error('Error parsing tokens:', e);
+                                action[key] = [];
+                            }}
+                        }} else {{
+                            action[key] = value;
+                        }}
+                    }}
+                }}
+                
+                try {{
+                    const response = await fetch('/web/step', {{
+                        method: 'POST',
+                        headers: {{ 'Content-Type': 'application/json' }},
+                        body: JSON.stringify({{ action }})
+                    }});
+                    
+                    if (!response.ok) {{
+                        throw new Error(`HTTP error! status: ${{response.status}}`);
+                    }}
+                    
+                    const result = await response.json();
+                    console.log('Step result:', result);
+                }} catch (error) {{
+                    console.error('Error submitting action:', error);
+                    alert('Error submitting action: ' + error.message);
+                }}
+            }}
+            
+            async resetEnvironment() {{
+                try {{
+                    const response = await fetch('/web/reset', {{
+                        method: 'POST',
+                        headers: {{ 'Content-Type': 'application/json' }}
+                    }});
+                    
+                    if (!response.ok) {{
+                        throw new Error(`HTTP error! status: ${{response.status}}`);
+                    }}
+                    
+                    const result = await response.json();
+                    console.log('Reset result:', result);
+                }} catch (error) {{
+                    console.error('Error resetting environment:', error);
+                    alert('Error resetting environment: ' + error.message);
+                }}
+            }}
+            
+            async getState() {{
+                try {{
+                    const response = await fetch('/web/state');
+                    const state = await response.json();
+                    console.log('Current state:', state);
+                    alert('Current state: ' + JSON.stringify(state, null, 2));
+                }} catch (error) {{
+                    console.error('Error getting state:', error);
+                    alert('Error getting state: ' + error.message);
+                }}
+            }}
+            
+            updateConnectionStatus(connected) {{
+                const indicator = document.getElementById('connection-status');
+                if (connected) {{
+                    indicator.className = 'status-indicator status-connected';
+                }} else {{
+                    indicator.className = 'status-indicator status-disconnected';
+                }}
+            }}
+            
+            updateUI(episodeState) {{
+                // Check if this is a chat environment
+                const isChatEnv = document.getElementById('chat-messages') !== null;
+                
+                // Update current state
+                document.getElementById('env-status').textContent = 
+                    episodeState.is_reset ? 'Reset' : 'Running';
+                document.getElementById('episode-id').textContent = 
+                    episodeState.episode_id || '-';
+                document.getElementById('step-count').textContent = 
+                    episodeState.step_count.toString();
+                
+                if (isChatEnv) {{
+                    // Update chat interface
+                    this.updateChatInterface(episodeState);
+                }} else {{
+                    // Update traditional observation display
+                    const observationDiv = document.getElementById('current-observation');
+                    if (episodeState.current_observation) {{
+                        observationDiv.textContent = JSON.stringify(
+                            episodeState.current_observation, null, 2
+                        );
+                    }} else {{
+                        observationDiv.textContent = 'No observation yet';
+                    }}
+                }}
+                
+                // Update action logs
+                const logsDiv = document.getElementById('action-logs');
+                if (episodeState.action_logs.length === 0) {{
+                    logsDiv.innerHTML = 'No actions taken yet';
+                }} else {{
+                    logsDiv.innerHTML = episodeState.action_logs.map(log => `
+                        <div class="log-entry">
+                            <div class="log-timestamp">${{log.timestamp}} (Step ${{log.step_count}})</div>
+                            <div class="log-action">Action: ${{JSON.stringify(log.action, null, 2)}}</div>
+                            <div class="log-observation">Observation: ${{JSON.stringify(log.observation, null, 2)}}</div>
+                            <div>
+                                <span class="log-reward">Reward: ${{log.reward !== null ? log.reward : 'None'}}</span>
+                                ${{log.done ? '<span class="log-done">DONE</span>' : ''}}
+                            </div>
+                        </div>
+                    `).join('');
+                }}
+            }}
+            
+            updateChatInterface(episodeState) {{
+                const chatMessages = document.getElementById('chat-messages');
+                if (!chatMessages) return;
+                
+                // Clear existing messages (except system message)
+                const systemMessage = chatMessages.querySelector('.chat-message.system');
+                chatMessages.innerHTML = '';
+                if (systemMessage) {{
+                    chatMessages.appendChild(systemMessage);
+                }}
+                
+                // Add messages from current observation
+                if (episodeState.current_observation && episodeState.current_observation.messages) {{
+                    episodeState.current_observation.messages.forEach(msg => {{
+                        this.addMessageToChat(msg.role, msg.content);
+                    }});
+                }}
+            }}
+        }}
+        
+        // Initialize the web interface when the page loads
+        document.addEventListener('DOMContentLoaded', () => {{
+            new OpenEnvWebInterface();
+        }});
+    </script>
+</body>
+</html>
+    """.replace('{_generate_action_form_fields(action_fields)}', _generate_action_form_fields(action_fields))
+
+
+def _generate_instructions_section(metadata: Optional[EnvironmentMetadata]) -> str:
+    """Generate the instructions section with environment documentation."""
+    if not metadata or not metadata.readme_content:
+        return ''
+    
+    # Convert markdown to HTML (basic conversion)
+    import re
+    html_content = _markdown_to_html(metadata.readme_content)
+    
+    return f'''
+                <!-- Instructions Section -->
+                <div class="instructions-section">
+                    <div class="instructions-header">
+                        <h3 class="instructions-title">{metadata.name}</h3>
+                        <button class="instructions-toggle" id="instructions-toggle">Show Instructions</button>
+                    </div>
+                    <div class="instructions-content" id="instructions-content">
+                        <div class="instructions-readme">
+                            {html_content}
+                        </div>
+                    </div>
+                </div>
+    '''
+
+
+def _extract_action_fields(action_cls: Type[Action]) -> List[Dict[str, Any]]:
+    """Extract enhanced field metadata from Action class for form generation."""
+    import typing
+    from typing import get_origin, get_args
+    
+    action_fields = []
+    if not hasattr(action_cls, '__dataclass_fields__'):
+        return action_fields
+    
+    for field_name, field_info in action_cls.__dataclass_fields__.items():
+        if field_name == 'metadata':
+            continue
+            
+        field_type = field_info.type
+        field_metadata = _extract_field_metadata(field_name, field_info)
+        
+        # Determine input type based on field type
+        input_type = _determine_input_type(field_type)
+        
+        # Check if field is required
+        is_required = field_info.default is field_info.default_factory
+        
+        action_fields.append({
+            'name': field_name,
+            'type': input_type,
+            'required': is_required,
+            'description': field_metadata.get('description', ''),
+            'default_value': field_metadata.get('default_value'),
+            'choices': field_metadata.get('choices', []),
+            'min_value': field_metadata.get('min_value'),
+            'max_value': field_metadata.get('max_value'),
+            'placeholder': field_metadata.get('placeholder', ''),
+            'help_text': field_metadata.get('help_text', ''),
+        })
+    
+    return action_fields
+
+
+def _extract_field_metadata(field_name: str, field_info) -> Dict[str, Any]:
+    """Extract metadata from dataclass field including docstring and type hints."""
+    import typing
+    from typing import get_origin, get_args, Literal, Union, Optional
+    
+    metadata = {}
+    
+    # Extract description from field docstring or annotation
+    if hasattr(field_info, 'metadata') and field_info.metadata:
+        # Check for custom metadata
+        for meta in field_info.metadata:
+            if isinstance(meta, dict):
+                metadata.update(meta)
+    
+    # Extract type information
+    field_type = field_info.type
+    origin = get_origin(field_type)
+    
+    # Handle Literal types for dropdown choices
+    if origin is Literal:
+        args = get_args(field_type)
+        metadata['choices'] = list(args)
+    
+    # Handle Optional types
+    if origin is Union:
+        args = get_args(field_type)
+        if len(args) == 2 and type(None) in args:
+            # This is Optional[SomeType]
+            non_none_type = args[0] if args[1] is type(None) else args[1]
+            metadata['optional'] = True
+            # Recursively check the non-None type for choices
+            if get_origin(non_none_type) is Literal:
+                metadata['choices'] = list(get_args(non_none_type))
+        else:
+            # Regular Union type
+            metadata['choices'] = [str(arg) for arg in args if arg is not type(None)]
+    
+    # Handle numeric constraints
+    if field_type in (int, float):
+        # Check for common constraint patterns in field name
+        if 'count' in field_name.lower() or 'num' in field_name.lower():
+            metadata['min_value'] = 0
+        if 'id' in field_name.lower():
+            metadata['min_value'] = 0
+    
+    # Generate placeholder text
+    if 'message' in field_name.lower():
+        metadata['placeholder'] = f'Enter {field_name.replace("_", " ")}...'
+    elif 'code' in field_name.lower():
+        metadata['placeholder'] = 'Enter Python code here...'
+    elif 'tokens' in field_name.lower():
+        metadata['placeholder'] = 'Enter comma-separated token IDs (e.g., 1,2,3,4,5)'
+    else:
+        metadata['placeholder'] = f'Enter {field_name.replace("_", " ")}...'
+    
+    # Generate help text based on field name and type
+    if 'action_id' in field_name.lower():
+        metadata['help_text'] = 'The action ID to execute in the environment'
+    elif 'game_name' in field_name.lower():
+        metadata['help_text'] = 'Name of the game or environment'
+    elif 'tokens' in field_name.lower():
+        metadata['help_text'] = 'Token IDs as a comma-separated list of integers'
+    elif 'code' in field_name.lower():
+        metadata['help_text'] = 'Python code to execute in the environment'
+    elif 'message' in field_name.lower():
+        metadata['help_text'] = 'Text message to send'
+    
+    return metadata
+
+
+def _determine_input_type(field_type) -> str:
+    """Determine the appropriate HTML input type for a field type."""
+    import typing
+    from typing import get_origin, get_args, Literal, Union
+    
+    # Handle direct types
+    if field_type == str:
+        return "text"
+    elif field_type == int:
+        return "number"
+    elif field_type == float:
+        return "number"
+    elif field_type == bool:
+        return "checkbox"
+    
+    # Handle complex types
+    origin = get_origin(field_type)
+    
+    if origin is Literal:
+        return "select"
+    elif origin is Union:
+        args = get_args(field_type)
+        if len(args) == 2 and type(None) in args:
+            # Optional type - use the non-None type
+            non_none_type = args[0] if args[1] is type(None) else args[1]
+            return _determine_input_type(non_none_type)
+        elif all(isinstance(arg, str) for arg in args if arg is not type(None)):
+            return "select"
+        else:
+            return "text"
+    elif hasattr(field_type, '__name__') and 'Tensor' in field_type.__name__:
+        return "tensor"
+    else:
+        return "text"
+
+
+def _markdown_to_html(markdown: str) -> str:
+    """Convert basic markdown to HTML for README display."""
+    import html
+    import re
+    
+    # Escape HTML first
+    html_content = html.escape(markdown)
+    
+    # Convert headers
+    html_content = re.sub(r'^# (.*?)$', r'<h1>\1</h1>', html_content, flags=re.MULTILINE)
+    html_content = re.sub(r'^## (.*?)$', r'<h2>\1</h2>', html_content, flags=re.MULTILINE)
+    html_content = re.sub(r'^### (.*?)$', r'<h3>\1</h3>', html_content, flags=re.MULTILINE)
+    
+    # Convert code blocks
+    html_content = re.sub(r'```(.*?)\n(.*?)\n```', r'<pre><code>\2</code></pre>', html_content, flags=re.DOTALL)
+    html_content = re.sub(r'`([^`]+)`', r'<code>\1</code>', html_content)
+    
+    # Convert bold and italic
+    html_content = re.sub(r'\*\*(.*?)\*\*', r'<strong>\1</strong>', html_content)
+    html_content = re.sub(r'\*(.*?)\*', r'<em>\1</em>', html_content)
+    
+    # Convert lists
+    html_content = re.sub(r'^- (.*?)$', r'<li>\1</li>', html_content, flags=re.MULTILINE)
+    html_content = re.sub(r'(<li>.*</li>)', r'<ul>\1</ul>', html_content, flags=re.DOTALL)
+    
+    # Convert line breaks
+    html_content = html_content.replace('\n', '<br>')
+    
+    return html_content
+
+
+def _generate_action_interface(action_fields: List[Dict[str, Any]], is_chat_env: bool) -> str:
+    """Generate either a chat interface or action form based on environment type."""
+    if is_chat_env:
+        return _generate_chat_interface()
+    else:
+        return _generate_action_form(action_fields)
+
+def _generate_chat_interface() -> str:
+    """Generate a chat-style interface for chat environments."""
+    return '''
+                <!-- Chat Interface -->
+                <div class="chat-interface">
+                    <h3>Chat Interface</h3>
+                    <div class="chat-messages" id="chat-messages">
+                        <div class="chat-message system">
+                            <div class="message-role">System</div>
+                            <div class="message-content">Chat environment ready. Send a message to start the conversation.</div>
+                        </div>
+                    </div>
+                    <div class="chat-input-container">
+                        <div class="role-selector">
+                            <label for="message-role">Role:</label>
+                            <select id="message-role">
+                                <option value="user">User</option>
+                                <option value="assistant">Assistant</option>
+                            </select>
+                        </div>
+                        <div class="message-input">
+                            <textarea id="message-input" placeholder="Type your message here..." rows="3"></textarea>
+                            <button class="btn" id="send-message-btn">Send Message</button>
+                        </div>
+                    </div>
+                </div>
+    '''
+
+def _generate_action_form(action_fields: List[Dict[str, Any]]) -> str:
+    """Generate a traditional action form for non-chat environments."""
+    return f'''
+                <!-- Action Form -->
+                <div class="action-form">
+                    <h3>Take Action</h3>
+                    <form id="action-form">
+                        {_generate_action_form_fields(action_fields)}
+                        <button type="submit" class="btn" id="step-btn">Step</button>
+                    </form>
+                </div>
+    '''
+
+def _generate_action_form_fields(action_fields: List[Dict[str, Any]]) -> str:
+    """Generate HTML form fields for action input with enhanced metadata."""
+    if not action_fields:
+        return '<p>No action fields available</p>'
+    
+    fields_html = []
+    for field in action_fields:
+        field_html = _generate_single_field(field)
+        fields_html.append(field_html)
+    
+    return '\n'.join(fields_html)
+
+
+def _generate_single_field(field: Dict[str, Any]) -> str:
+    """Generate HTML for a single form field with enhanced metadata."""
+    field_name = field['name']
+    field_type = field['type']
+    required = field['required']
+    placeholder = field.get('placeholder', '')
+    help_text = field.get('help_text', '')
+    choices = field.get('choices', [])
+    min_value = field.get('min_value')
+    max_value = field.get('max_value')
+    default_value = field.get('default_value')
+    
+    # Build label with required indicator
+    label_text = field_name.replace('_', ' ').title()
+    if required:
+        label_text += ' <span style="color: red;">*</span>'
+    
+    # Build input attributes
+    input_attrs = []
+    if required:
+        input_attrs.append('required')
+    if placeholder:
+        input_attrs.append(f'placeholder="{placeholder}"')
+    if min_value is not None:
+        input_attrs.append(f'min="{min_value}"')
+    if max_value is not None:
+        input_attrs.append(f'max="{max_value}"')
+    if default_value is not None:
+        input_attrs.append(f'value="{default_value}"')
+    
+    attrs_str = ' '.join(input_attrs)
+    
+    if field_type == 'checkbox':
+        return f'''
+            <div class="form-group">
+                <label>
+                    <input type="checkbox" name="{field_name}" value="true" {attrs_str}>
+                    {label_text}
+                </label>
+                {f'<small class="help-text">{help_text}</small>' if help_text else ''}
+            </div>
+        '''
+    
+    elif field_type == 'select':
+        options_html = []
+        if not required:
+            options_html.append(f'<option value="">-- Select {label_text} --</option>')
+        
+        for choice in choices:
+            selected = 'selected' if str(choice) == str(default_value) else ''
+            options_html.append(f'<option value="{choice}" {selected}>{choice}</option>')
+        
+        return f'''
+            <div class="form-group">
+                <label for="{field_name}">{label_text}:</label>
+                <select name="{field_name}" id="{field_name}" {attrs_str}>
+                    {''.join(options_html)}
+                </select>
+                {f'<small class="help-text">{help_text}</small>' if help_text else ''}
+            </div>
+        '''
+    
+    elif field_type == 'tensor':
+        return f'''
+            <div class="form-group">
+                <label for="{field_name}">{label_text} (comma-separated integers):</label>
+                <input type="text" name="{field_name}" id="{field_name}" {attrs_str}>
+                <small class="help-text">{help_text or 'Enter token IDs as comma-separated integers (e.g., 1,2,3,4,5)'}</small>
+            </div>
+        '''
+    
+    elif field_type == 'text' and ('message' in field_name.lower() or 'code' in field_name.lower()):
+        return f'''
+            <div class="form-group">
+                <label for="{field_name}">{label_text}:</label>
+                <textarea name="{field_name}" id="{field_name}" rows="3" {attrs_str}></textarea>
+                {f'<small class="help-text">{help_text}</small>' if help_text else ''}
+            </div>
+        '''
+    
+    else:
+        return f'''
+            <div class="form-group">
+                <label for="{field_name}">{label_text}:</label>
+                <input type="{field_type}" name="{field_name}" id="{field_name}" {attrs_str}>
+                {f'<small class="help-text">{help_text}</small>' if help_text else ''}
+            </div>
+        '''

src/core/http_env_client.py

@@ -0,0 +1,175 @@
+"""
+core/runner_env.py
+Minimal HTTP-based environment client.
+- Talks to a single env worker exposing: POST /reset, POST /step
+
+Future hooks (commented below) for:
+- episode_id, seed on reset
+- request_id on step
+- custom headers (auth/trace)
+"""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from typing import TYPE_CHECKING, Any, Dict, Generic, Optional, Type, TypeVar
+from .containers.runtime import LocalDockerProvider
+import requests
+
+from .types import StepResult
+
+if TYPE_CHECKING:
+    from .containers.runtime import ContainerProvider
+
+ActT = TypeVar("ActT")
+ObsT = TypeVar("ObsT")
+EnvClientT = TypeVar("EnvClientT", bound="HTTPEnvClient")
+
+
+class HTTPEnvClient(ABC, Generic[ActT, ObsT]):
+    def __init__(
+        self,
+        base_url: str,
+        request_timeout_s: float = 15.0,
+        default_headers: Optional[Dict[str, str]] = None,
+        provider: Optional["ContainerProvider"] = None,
+    ):
+        self._base = base_url.rstrip("/")
+        self._timeout = float(request_timeout_s)
+        self._http = requests.Session()
+        self._headers = default_headers or {}
+        self._provider = provider
+
+    @classmethod
+    def from_docker_image(
+        cls: Type[EnvClientT],
+        image: str,
+        provider: Optional["ContainerProvider"] = None,
+    ) -> EnvClientT:
+        """
+        Create an environment client by spinning up a Docker container locally.
+
+        This is a development utility that:
+        1. Starts a Docker container from the specified image
+        2. Waits for the server to be ready
+        3. Creates and returns a client instance connected to the container
+
+        Note: The container lifecycle management is left to the user or higher-level
+        orchestration. The container will keep running until manually stopped.
+
+        Args:
+            image: Docker image name to run (e.g., "echo-env:latest")
+            provider: Container provider to use (defaults to LocalDockerProvider)
+
+        Returns:
+            An instance of the client class connected to the running container
+
+        Example:
+            >>> from envs.coding_env.client import CodingEnv
+            >>> from envs.coding_env.models import CodeAction
+            >>>
+            >>> # Create environment from image
+            >>> env = CodingEnv.from_docker_image("coding-env:latest")
+            >>>
+            >>> # Use the environment
+            >>> result = env.reset()
+            >>> print(result.observation)
+            >>>
+            >>> step_result = env.step(CodeAction(code="print('hello')"))
+            >>> print(step_result.observation.stdout)
+            >>>
+            >>> # Cleanup (optional)
+            >>> env.close()
+        """
+
+        # Use default provider if none provided
+        if provider is None:
+            provider = LocalDockerProvider()
+
+        # 1. Start container
+        base_url = provider.start_container(image)
+
+        # 2. Wait for server to be ready
+        provider.wait_for_ready(base_url)
+
+        # 3. Create and return client instance with provider reference
+        return cls(base_url=base_url, provider=provider)
+
+    @abstractmethod
+    def _step_payload(self, action: ActT) -> dict:
+        """Convert an Action object to the JSON body expected by the env server."""
+        raise NotImplementedError
+
+    @abstractmethod
+    def _parse_result(self, payload: dict) -> StepResult[ObsT]:
+        """Convert a JSON response from the env server to StepResult[ObsT]."""
+        raise NotImplementedError
+
+    @abstractmethod
+    def _parse_state(self, payload: dict) -> Any:
+        """Convert a JSON response from the state endpoint to a State object."""
+        raise NotImplementedError
+
+    # ---------- Environment Server Interface Methods ----------
+    def reset(self) -> StepResult[ObsT]:
+        body: Dict[str, Any] = {}
+        # TODO: later:
+        # body["seed"] = seed
+        # body["episode_id"] = episode_id
+        r = self._http.post(
+            f"{self._base}/reset",
+            json=body,
+            headers=self._headers,
+            timeout=self._timeout,
+        )
+        r.raise_for_status()
+        return self._parse_result(r.json())
+
+    def step(self, action: ActT) -> StepResult[ObsT]:
+        body: Dict[str, Any] = {
+            "action": self._step_payload(action),
+            "timeout_s": int(self._timeout),
+        }
+        # TODO: later:
+        # body["request_id"] = str(uuid.uuid4())
+        # body["episode_id"] = current_episode_id
+        r = self._http.post(
+            f"{self._base}/step",
+            json=body,
+            headers=self._headers,
+            timeout=self._timeout,
+        )
+        r.raise_for_status()
+        return self._parse_result(r.json())
+
+    def state(self) -> Any:
+        """
+        Get the current environment state from the server.
+
+        Returns:
+            State object with environment state information (e.g., episode_id, step_count)
+
+        Example:
+            >>> client = EchoEnv.from_docker_image("echo-env:latest")
+            >>> result = client.reset()
+            >>> state = client.state()
+            >>> print(state.episode_id)
+            >>> print(state.step_count)
+        """
+        r = self._http.get(
+            f"{self._base}/state",
+            headers=self._headers,
+            timeout=self._timeout,
+        )
+        r.raise_for_status()
+        return self._parse_state(r.json())
+
+    def close(self) -> None:
+        """
+        Close the environment and clean up resources.
+
+        If this client was created via from_docker_image(), this will stop
+        and remove the associated container.
+        """
+        if self._provider is not None:
+            self._provider.stop_container()

src/core/tools/__init__.py

@@ -0,0 +1,11 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""Core tools for code execution and other utilities."""
+
+from .local_python_executor import PyExecutor
+
+__all__ = ["PyExecutor"]

src/core/tools/local_python_executor.py

@@ -0,0 +1,105 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+Local Python Executor.
+
+This module provides functionality for executing Python code locally by wrapping
+the smolagents LocalPythonExecutor.
+"""
+
+from smolagents import LocalPythonExecutor
+
+from core.env_server.types import CodeExecResult
+
+
+class PyExecutor:
+    """
+    Wrapper around smolagents LocalPythonExecutor for executing Python code.
+
+    This class provides a simple interface to execute Python code in a subprocess
+    and capture the results including stdout, stderr, and exit code.
+
+    Args:
+        additional_imports: List of additional module imports to authorize.
+                          For example: ["numpy", "pandas", "matplotlib"]
+                          These will be added to the base authorized imports.
+
+    Example:
+        >>> # Basic usage with default imports
+        >>> executor = PyExecutor()
+        >>> result = executor.run("print('Hello, World!')")
+        >>> print(result.stdout)  # "Hello, World!\n"
+        >>> print(result.exit_code)  # 0
+        >>>
+        >>> # Usage with additional imports
+        >>> executor = PyExecutor(additional_imports=["numpy", "pandas"])
+        >>> result = executor.run("import numpy as np\\nprint(np.array([1, 2, 3]))")
+        >>> print(result.stdout)  # "[1 2 3]\n"
+    """
+
+    def __init__(self, additional_imports: list[str] | None = None):
+        """
+        Initialize the PyExecutor with a LocalPythonExecutor instance.
+
+        Args:
+            additional_imports: List of additional module names to authorize for import.
+                              Defaults to an empty list if not provided.
+        """
+        if additional_imports is None:
+            additional_imports = []
+        self._executor = LocalPythonExecutor(
+            additional_authorized_imports=additional_imports
+        )
+        # Initialize tools to make BASE_PYTHON_TOOLS available (including print)
+        self._executor.send_tools({})
+
+    def run(self, code: str) -> CodeExecResult:
+        """
+        Execute Python code and return the result.
+
+        Args:
+            code: Python code string to execute
+
+        Returns:
+            CodeExecResult containing stdout, stderr, and exit_code
+
+        Example:
+            >>> executor = PyExecutor()
+            >>> result = executor.run("x = 5 + 3\\nprint(x)")
+            >>> print(result.stdout)  # "8\n"
+            >>> print(result.exit_code)  # 0
+            >>>
+            >>> # Error handling
+            >>> result = executor.run("1 / 0")
+            >>> print(result.exit_code)  # 1
+            >>> print(result.stderr)  # Contains error message
+        """
+        try:
+            # Execute the code using LocalPythonExecutor
+            # LocalPythonExecutor returns a CodeOutput object with output, logs, is_final_answer
+            exec_result = self._executor(code)
+
+            # Extract the logs (which contain print outputs) as stdout
+            # The output field contains the return value of the code
+            stdout = exec_result.logs
+            stderr = ""
+            exit_code = 0  # Success
+
+            return CodeExecResult(
+                stdout=stdout,
+                stderr=stderr,
+                exit_code=exit_code,
+            )
+
+        except Exception as e:
+            # LocalPythonExecutor raises InterpreterError for various issues
+            # (syntax errors, forbidden operations, runtime errors, etc.)
+            return CodeExecResult(
+                stdout="",
+                stderr=str(e),
+                exit_code=1,  # Non-zero indicates error
+            )

src/core/types.py

@@ -0,0 +1,22 @@
+# Type definitions for EnvTorch
+from dataclasses import dataclass
+from typing import Any, Generic, Optional, TypeVar
+
+# Generic type for observations
+ObsT = TypeVar("ObsT")  # TypeVar for typehinting in IDEs
+
+
+@dataclass
+class StepResult(Generic[ObsT]):
+    """
+    Represents the result of one environment step.
+
+    Attributes:
+        observation: The environment's observation after the action.
+        reward: Scalar reward for this step (optional).
+        done: Whether the episode is finished.
+    """
+
+    observation: ObsT
+    reward: Optional[float] = None
+    done: bool = False

src/envs/sumo_rl_env/README.md

@@ -0,0 +1,341 @@
+# SUMO-RL Environment
+
+Integration of traffic signal control with the OpenEnv framework via SUMO (Simulation of Urban MObility) and SUMO-RL.
+
+## Overview
+
+This environment enables reinforcement learning for **traffic signal control** using SUMO, a microscopic traffic simulation package. Train RL agents to optimize traffic light timing and minimize vehicle delays.
+
+**Key Features**:
+- **Realistic traffic simulation** via SUMO
+- **Single-agent mode** for single intersection control
+- **Configurable rewards** (waiting time, queue, pressure, speed)
+- **Multiple networks** supported (custom .net.xml and .rou.xml files)
+- **Docker-ready** with pre-bundled example network
+
+## Quick Start
+
+### Using Docker (Recommended)
+
+```python
+from envs.sumo_rl_env import SumoRLEnv, SumoAction
+
+# Automatically starts container
+env = SumoRLEnv.from_docker_image("sumo-rl-env:latest")
+
+# Reset environment
+result = env.reset()
+print(f"Observation shape: {result.observation.observation_shape}")
+print(f"Available actions: {result.observation.action_mask}")
+
+# Take action (select next green phase)
+result = env.step(SumoAction(phase_id=1))
+print(f"Reward: {result.reward}, Done: {result.done}")
+
+# Get state
+state = env.state()
+print(f"Simulation time: {state.sim_time}")
+print(f"Total vehicles: {state.total_vehicles}")
+print(f"Mean waiting time: {state.mean_waiting_time}")
+
+# Cleanup
+env.close()
+```
+
+### Building the Docker Image
+
+```bash
+cd OpenEnv
+
+# Build base image first (if not already built)
+docker build -t envtorch-base:latest -f src/core/containers/images/Dockerfile .
+
+# Build SUMO-RL environment
+docker build -f src/envs/sumo_rl_env/server/Dockerfile -t sumo-rl-env:latest .
+```
+
+### Running with Different Configurations
+
+```bash
+# Default: single-intersection
+docker run -p 8000:8000 sumo-rl-env:latest
+
+# Longer simulation
+docker run -p 8000:8000 \
+  -e SUMO_NUM_SECONDS=50000 \
+  sumo-rl-env:latest
+
+# Different reward function
+docker run -p 8000:8000 \
+  -e SUMO_REWARD_FN=queue \
+  sumo-rl-env:latest
+
+# Custom seed for reproducibility
+docker run -p 8000:8000 \
+  -e SUMO_SEED=123 \
+  sumo-rl-env:latest
+```
+
+## Observation
+
+The observation is a vector containing:
+- **Phase one-hot**: Current active green phase (one-hot encoded)
+- **Min green flag**: Binary indicator if minimum green time has passed
+- **Lane densities**: Number of vehicles / lane capacity for each incoming lane
+- **Lane queues**: Number of queued vehicles / lane capacity for each incoming lane
+
+Observation size varies by network topology (depends on number of phases and lanes).
+
+**Default (single-intersection)**:
+- 4 green phases
+- 8 incoming lanes
+- Observation size: ~21 elements
+
+## Action Space
+
+The action space is discrete and represents selecting the next green phase to activate.
+
+- **Action type**: Discrete
+- **Action range**: `[0, num_green_phases - 1]`
+- **Default (single-intersection)**: 4 actions (one per green phase)
+
+When a phase change is requested, SUMO automatically inserts a yellow phase before switching.
+
+## Rewards
+
+Default reward function is **change in cumulative waiting time**:
+```
+reward = -(total_waiting_time_now - total_waiting_time_previous)
+```
+
+Positive rewards indicate waiting time decreased (good).
+
+### Available Reward Functions
+
+Set via `SUMO_REWARD_FN` environment variable:
+
+- **`diff-waiting-time`** (default): Change in cumulative waiting time
+- **`average-speed`**: Average speed of all vehicles
+- **`queue`**: Negative total queue length
+- **`pressure`**: Pressure metric (incoming - outgoing vehicles)
+
+## Configuration
+
+### Environment Variables
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `SUMO_NET_FILE` | `/app/nets/single-intersection.net.xml` | Network topology file |
+| `SUMO_ROUTE_FILE` | `/app/nets/single-intersection.rou.xml` | Vehicle routes file |
+| `SUMO_NUM_SECONDS` | `20000` | Simulation duration (seconds) |
+| `SUMO_DELTA_TIME` | `5` | Seconds between agent actions |
+| `SUMO_YELLOW_TIME` | `2` | Yellow phase duration (seconds) |
+| `SUMO_MIN_GREEN` | `5` | Minimum green time (seconds) |
+| `SUMO_MAX_GREEN` | `50` | Maximum green time (seconds) |
+| `SUMO_REWARD_FN` | `diff-waiting-time` | Reward function name |
+| `SUMO_SEED` | `42` | Random seed (use for reproducibility) |
+
+### Using Custom Networks
+
+To use your own SUMO network:
+
+```python
+from envs.sumo_rl_env import SumoRLEnv
+
+env = SumoRLEnv.from_docker_image(
+    "sumo-rl-env:latest",
+    volumes={
+        "/path/to/your/nets": {"bind": "/nets", "mode": "ro"}
+    },
+    environment={
+        "SUMO_NET_FILE": "/nets/my-network.net.xml",
+        "SUMO_ROUTE_FILE": "/nets/my-routes.rou.xml",
+    }
+)
+```
+
+Your network directory should contain:
+- `.net.xml` - Network topology (roads, junctions, traffic lights)
+- `.rou.xml` - Vehicle routes (trip definitions, flow rates)
+
+## API Reference
+
+### SumoAction
+
+```python
+@dataclass
+class SumoAction(Action):
+    phase_id: int  # Green phase to activate (0 to num_phases-1)
+    ts_id: str = "0"  # Traffic signal ID (for multi-agent)
+```
+
+### SumoObservation
+
+```python
+@dataclass
+class SumoObservation(Observation):
+    observation: List[float]  # Observation vector
+    observation_shape: List[int]  # Shape for reshaping
+    action_mask: List[int]  # Valid action indices
+    sim_time: float  # Current simulation time
+    done: bool  # Episode finished
+    reward: Optional[float]  # Reward from last action
+    metadata: Dict  # System metrics
+```
+
+### SumoState
+
+```python
+@dataclass
+class SumoState(State):
+    episode_id: str  # Unique episode ID
+    step_count: int  # Steps taken
+    net_file: str  # Network file path
+    route_file: str  # Route file path
+    sim_time: float  # Current simulation time
+    total_vehicles: int  # Total vehicles in simulation
+    total_waiting_time: float  # Cumulative waiting time
+    mean_waiting_time: float  # Mean waiting time
+    mean_speed: float  # Mean vehicle speed
+    # ... configuration parameters
+```
+
+## Example Training Loop
+
+```python
+from envs.sumo_rl_env import SumoRLEnv, SumoAction
+import numpy as np
+
+# Start environment
+env = SumoRLEnv.from_docker_image("sumo-rl-env:latest")
+
+# Training loop
+for episode in range(10):
+    result = env.reset()
+    episode_reward = 0
+    steps = 0
+
+    while not result.done and steps < 1000:
+        # Random policy (replace with your RL agent)
+        action_id = np.random.choice(result.observation.action_mask)
+
+        # Take action
+        result = env.step(SumoAction(phase_id=action_id))
+
+        episode_reward += result.reward or 0
+        steps += 1
+
+        # Print progress every 100 steps
+        if steps % 100 == 0:
+            state = env.state()
+            print(f"Step {steps}: "
+                  f"reward={result.reward:.2f}, "
+                  f"vehicles={state.total_vehicles}, "
+                  f"waiting={state.mean_waiting_time:.2f}")
+
+    print(f"Episode {episode}: total_reward={episode_reward:.2f}, steps={steps}")
+
+env.close()
+```
+
+## Performance Notes
+
+### Simulation Speed
+
+- **Reset time**: 1-5 seconds (starts new SUMO simulation)
+- **Step time**: ~50-200ms per step (depends on network size)
+- **Episode duration**: Minutes (20,000 sim seconds with delta_time=5 → ~4,000 steps)
+
+### Optimization
+
+For faster simulation:
+1. Reduce `SUMO_NUM_SECONDS` for shorter episodes
+2. Increase `SUMO_DELTA_TIME` for fewer decisions
+3. Use simpler networks with fewer vehicles
+
+## Architecture
+
+```
+┌─────────────────────────────────┐
+│ Client: SumoRLEnv               │
+│  .step(phase_id=1)              │
+└──────────────┬──────────────────┘
+               │ HTTP
+┌──────────────▼──────────────────┐
+│ FastAPI Server (Docker)         │
+│   SumoEnvironment               │
+│     ├─ Wraps sumo_rl           │
+│     ├─ Single-agent mode       │
+│     └─ No GUI                  │
+└──────────────┬──────────────────┘
+               │
+┌──────────────▼──────────────────┐
+│ SUMO Simulator                  │
+│  - Reads .net.xml (network)     │
+│  - Reads .rou.xml (routes)      │
+│  - Simulates traffic flow       │
+│  - Provides observations        │
+└─────────────────────────────────┘
+```
+
+## Bundled Network
+
+The default `single-intersection` network is a simple 4-way intersection with:
+- **4 incoming roads** (North, South, East, West)
+- **4 green phases** (NS straight, NS left, EW straight, EW left)
+- **Vehicle flow**: Continuous stream with varying rates
+
+## Limitations
+
+- **No GUI in Docker**: SUMO GUI requires X server (not available in containers)
+- **Single-agent only**: Multi-agent (multiple intersections) coming in future version
+- **Fixed network per container**: Each container uses one network topology
+- **Memory usage**: ~500MB for small networks, 2-4GB for large city networks
+
+## Troubleshooting
+
+### Container won't start
+```bash
+# Check logs
+docker logs <container-id>
+
+# Verify network files exist
+docker run sumo-rl-env:latest ls -la /app/nets/
+```
+
+### "SUMO_HOME not set" error
+This should be automatic in Docker. If running locally:
+```bash
+export SUMO_HOME=/usr/share/sumo
+```
+
+### Slow performance
+- Reduce simulation duration: `SUMO_NUM_SECONDS=5000`
+- Increase action interval: `SUMO_DELTA_TIME=10`
+- Use smaller networks with fewer vehicles
+
+## References
+
+- [SUMO Documentation](https://sumo.dlr.de/docs/)
+- [SUMO-RL GitHub](https://github.com/LucasAlegre/sumo-rl)
+- [SUMO-RL Paper](https://peerj.com/articles/cs-575/)
+- [RESCO Benchmarks](https://github.com/jault/RESCO)
+
+## Citation
+
+If you use SUMO-RL in your research, please cite:
+
+```bibtex
+@misc{sumorl,
+    author = {Lucas N. Alegre},
+    title = {{SUMO-RL}},
+    year = {2019},
+    publisher = {GitHub},
+    journal = {GitHub repository},
+    howpublished = {\url{https://github.com/LucasAlegre/sumo-rl}},
+}
+```
+
+## License
+
+This integration is licensed under the BSD-style license. SUMO-RL and SUMO have their own licenses.

src/envs/sumo_rl_env/__init__.py

@@ -0,0 +1,31 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+SUMO-RL Environment for OpenEnv.
+
+This module provides OpenEnv integration for traffic signal control using
+SUMO (Simulation of Urban MObility) via the SUMO-RL library.
+
+Example:
+    >>> from envs.sumo_rl_env import SumoRLEnv, SumoAction
+    >>>
+    >>> # Connect to a running server or start via Docker
+    >>> env = SumoRLEnv.from_docker_image("sumo-rl-env:latest")
+    >>>
+    >>> # Reset and interact
+    >>> result = env.reset()
+    >>> result = env.step(SumoAction(phase_id=1))
+    >>> print(result.reward, result.done)
+    >>>
+    >>> # Cleanup
+    >>> env.close()
+"""
+
+from .client import SumoRLEnv
+from .models import SumoAction, SumoObservation, SumoState
+
+__all__ = ["SumoRLEnv", "SumoAction", "SumoObservation", "SumoState"]

src/envs/sumo_rl_env/client.py

@@ -0,0 +1,145 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+HTTP client for SUMO-RL environment.
+
+This module provides a client to interact with the SUMO traffic signal
+control environment over HTTP.
+"""
+
+from typing import Any, Dict
+
+from core.http_env_client import HTTPEnvClient
+from core.types import StepResult
+
+from .models import SumoAction, SumoObservation, SumoState
+
+
+class SumoRLEnv(HTTPEnvClient[SumoAction, SumoObservation]):
+    """
+    HTTP client for SUMO-RL traffic signal control environment.
+
+    This client communicates with a SUMO environment server to control
+    traffic signals using reinforcement learning.
+
+    Example:
+        >>> # Start container and connect
+        >>> env = SumoRLEnv.from_docker_image("sumo-rl-env:latest")
+        >>>
+        >>> # Reset environment
+        >>> result = env.reset()
+        >>> print(f"Observation shape: {result.observation.observation_shape}")
+        >>> print(f"Action space: {result.observation.action_mask}")
+        >>>
+        >>> # Take action
+        >>> result = env.step(SumoAction(phase_id=1))
+        >>> print(f"Reward: {result.reward}, Done: {result.done}")
+        >>>
+        >>> # Get state
+        >>> state = env.state()
+        >>> print(f"Sim time: {state.sim_time}, Total vehicles: {state.total_vehicles}")
+        >>>
+        >>> # Cleanup
+        >>> env.close()
+
+    Example with custom network:
+        >>> # Use custom SUMO network via volume mount
+        >>> env = SumoRLEnv.from_docker_image(
+        ...     "sumo-rl-env:latest",
+        ...     port=8000,
+        ...     volumes={
+        ...         "/path/to/my/nets": {"bind": "/nets", "mode": "ro"}
+        ...     },
+        ...     environment={
+        ...         "SUMO_NET_FILE": "/nets/my-network.net.xml",
+        ...         "SUMO_ROUTE_FILE": "/nets/my-routes.rou.xml",
+        ...     }
+        ... )
+
+    Example with configuration:
+        >>> # Adjust simulation parameters
+        >>> env = SumoRLEnv.from_docker_image(
+        ...     "sumo-rl-env:latest",
+        ...     environment={
+        ...         "SUMO_NUM_SECONDS": "10000",
+        ...         "SUMO_DELTA_TIME": "10",
+        ...         "SUMO_REWARD_FN": "queue",
+        ...         "SUMO_SEED": "123",
+        ...     }
+        ... )
+    """
+
+    def _step_payload(self, action: SumoAction) -> Dict[str, Any]:
+        """
+        Convert SumoAction to JSON payload for HTTP request.
+
+        Args:
+            action: SumoAction containing phase_id to execute.
+
+        Returns:
+            Dictionary payload for step endpoint.
+        """
+        return {
+            "phase_id": action.phase_id,
+            "ts_id": action.ts_id,
+        }
+
+    def _parse_result(self, payload: Dict[str, Any]) -> StepResult[SumoObservation]:
+        """
+        Parse step result from HTTP response JSON.
+
+        Args:
+            payload: JSON response from step endpoint.
+
+        Returns:
+            StepResult containing SumoObservation.
+        """
+        obs_data = payload.get("observation", {})
+
+        observation = SumoObservation(
+            observation=obs_data.get("observation", []),
+            observation_shape=obs_data.get("observation_shape", []),
+            action_mask=obs_data.get("action_mask", []),
+            sim_time=obs_data.get("sim_time", 0.0),
+            done=obs_data.get("done", False),
+            reward=obs_data.get("reward"),
+            metadata=obs_data.get("metadata", {}),
+        )
+
+        return StepResult(
+            observation=observation,
+            reward=payload.get("reward"),
+            done=payload.get("done", False),
+        )
+
+    def _parse_state(self, payload: Dict[str, Any]) -> SumoState:
+        """
+        Parse state from HTTP response JSON.
+
+        Args:
+            payload: JSON response from state endpoint.
+
+        Returns:
+            SumoState object.
+        """
+        return SumoState(
+            episode_id=payload.get("episode_id", ""),
+            step_count=payload.get("step_count", 0),
+            net_file=payload.get("net_file", ""),
+            route_file=payload.get("route_file", ""),
+            num_seconds=payload.get("num_seconds", 20000),
+            delta_time=payload.get("delta_time", 5),
+            yellow_time=payload.get("yellow_time", 2),
+            min_green=payload.get("min_green", 5),
+            max_green=payload.get("max_green", 50),
+            reward_fn=payload.get("reward_fn", "diff-waiting-time"),
+            sim_time=payload.get("sim_time", 0.0),
+            total_vehicles=payload.get("total_vehicles", 0),
+            total_waiting_time=payload.get("total_waiting_time", 0.0),
+            mean_waiting_time=payload.get("mean_waiting_time", 0.0),
+            mean_speed=payload.get("mean_speed", 0.0),
+        )

src/envs/sumo_rl_env/models.py

@@ -0,0 +1,110 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+"""
+Data models for SUMO-RL Environment.
+
+This module defines the Action, Observation, and State types for traffic
+signal control using SUMO (Simulation of Urban MObility).
+"""
+
+from dataclasses import dataclass, field
+from typing import Dict, List, Optional
+
+from core.env_server import Action, Observation, State
+
+
+@dataclass
+class SumoAction(Action):
+    """
+    Action for SUMO traffic signal control environment.
+
+    Represents selecting which traffic light phase to activate next.
+
+    Attributes:
+        phase_id: Index of the green phase to activate (0 to num_phases-1)
+        ts_id: Traffic signal ID (for multi-agent support, default "0")
+    """
+
+    phase_id: int
+    ts_id: str = "0"
+
+
+@dataclass
+class SumoObservation(Observation):
+    """
+    Observation from SUMO traffic signal environment.
+
+    Contains traffic metrics for decision-making.
+
+    Attributes:
+        observation: Flattened observation vector containing:
+                    - One-hot encoded current phase
+                    - Min green flag (binary)
+                    - Lane densities (normalized)
+                    - Lane queues (normalized)
+        observation_shape: Shape of observation for reshaping
+        action_mask: List of valid action indices
+        sim_time: Current simulation time in seconds
+        done: Whether episode is complete
+        reward: Reward from last action (None on reset)
+        metadata: Additional info (system metrics, etc.)
+    """
+
+    observation: List[float] = field(default_factory=list)
+    observation_shape: List[int] = field(default_factory=list)
+    action_mask: List[int] = field(default_factory=list)
+    sim_time: float = 0.0
+    done: bool = False
+    reward: Optional[float] = None
+    metadata: Dict = field(default_factory=dict)
+
+
+@dataclass
+class SumoState(State):
+    """
+    State of SUMO traffic signal environment.
+
+    Tracks both configuration and runtime state.
+
+    Configuration attributes:
+        net_file: Path to SUMO network file (.net.xml)
+        route_file: Path to SUMO route file (.rou.xml)
+        num_seconds: Total simulation duration in seconds
+        delta_time: Seconds between agent actions
+        yellow_time: Duration of yellow phase in seconds
+        min_green: Minimum green time per phase in seconds
+        max_green: Maximum green time per phase in seconds
+        reward_fn: Name of reward function used
+
+    Runtime attributes:
+        episode_id: Unique episode identifier
+        step_count: Number of steps taken in episode
+        sim_time: Current simulation time in seconds
+        total_vehicles: Total number of vehicles in simulation
+        total_waiting_time: Cumulative waiting time across all vehicles
+    """
+
+    # Episode tracking
+    episode_id: str = ""
+    step_count: int = 0
+
+    # SUMO configuration
+    net_file: str = ""
+    route_file: str = ""
+    num_seconds: int = 20000
+    delta_time: int = 5
+    yellow_time: int = 2
+    min_green: int = 5
+    max_green: int = 50
+    reward_fn: str = "diff-waiting-time"
+
+    # Runtime metrics
+    sim_time: float = 0.0
+    total_vehicles: int = 0
+    total_waiting_time: float = 0.0
+    mean_waiting_time: float = 0.0
+    mean_speed: float = 0.0

src/envs/sumo_rl_env/nets/single-intersection/single-intersection.edg.xml

@@ -0,0 +1,6 @@
+<edges>
+	<edge from="n" id="n_t" to="t" numLanes="2"/>
+	<edge from="w" id="w_t" to="t" numLanes="2"/>
+	<edge from="t" id="t_s" to="s" numLanes="2"/>
+	<edge from="t" id="t_e" to="e" numLanes="2"/>
+</edges>

src/envs/sumo_rl_env/nets/single-intersection/single-intersection.net.xml

@@ -0,0 +1,86 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- generated on seg 17 dez 2018 17:22:14 -02 by Netedit Version 0.32.0
+<?xml version="1.0" encoding="UTF-8"?>
+
+<configuration xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://sumo.dlr.de/xsd/netconvertConfiguration.xsd">
+
+    <input>
+        <sumo-net-file value="nets/single-intersection/single-intersection.net.xml"/>
+    </input>
+
+    <output>
+        <output-file value="/home/lucas/Documents/sumo-rl/nets/single-intersection/single-intersection2.net.xml"/>
+    </output>
+
+    <processing>
+        <no-turnarounds value="true"/>
+        <offset.disable-normalization value="true"/>
+        <lefthand value="false"/>
+        <junctions.corner-detail value="0"/>
+        <rectangular-lane-cut value="false"/>
+        <walkingareas value="false"/>
+    </processing>
+
+</configuration>
+-->
+
+<net version="0.27" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://sumo.dlr.de/xsd/net_file.xsd">
+
+    <location netOffset="150.00,150.00" convBoundary="0.00,0.00,300.00,300.00" origBoundary="-150.00,-150.00,150.00,150.00" projParameter="!"/>
+
+    <edge id=":t_0" function="internal">
+        <lane id=":t_0_0" index="0" speed="13.90" length="9.50" shape="145.05,151.45 145.05,141.95"/>
+        <lane id=":t_0_1" index="1" speed="13.90" length="9.50" shape="148.35,151.45 148.35,141.95"/>
+    </edge>
+    <edge id=":t_2" function="internal">
+        <lane id=":t_2_0" index="0" speed="13.90" length="9.50" shape="141.95,145.05 151.45,145.05"/>
+        <lane id=":t_2_1" index="1" speed="13.90" length="9.50" shape="141.95,148.35 151.45,148.35"/>
+    </edge>
+
+    <edge id="n_t" from="n" to="t" priority="-1">
+        <lane id="n_t_0" index="0" speed="13.90" length="148.55" shape="145.05,300.00 145.05,151.45"/>
+        <lane id="n_t_1" index="1" speed="13.90" length="148.55" shape="148.35,300.00 148.35,151.45"/>
+    </edge>
+    <edge id="t_e" from="t" to="e" priority="-1">
+        <lane id="t_e_0" index="0" speed="13.90" length="148.55" shape="151.45,145.05 300.00,145.05"/>
+        <lane id="t_e_1" index="1" speed="13.90" length="148.55" shape="151.45,148.35 300.00,148.35"/>
+    </edge>
+    <edge id="t_s" from="t" to="s" priority="-1">
+        <lane id="t_s_0" index="0" speed="13.90" length="141.95" shape="145.05,141.95 145.05,0.00"/>
+        <lane id="t_s_1" index="1" speed="13.90" length="141.95" shape="148.35,141.95 148.35,0.00"/>
+    </edge>
+    <edge id="w_t" from="w" to="t" priority="-1">
+        <lane id="w_t_0" index="0" speed="13.90" length="141.95" shape="0.00,145.05 141.95,145.05"/>
+        <lane id="w_t_1" index="1" speed="13.90" length="141.95" shape="0.00,148.35 141.95,148.35"/>
+    </edge>
+
+    <tlLogic id="t" type="static" programID="0" offset="0">
+        <phase duration="42" state="GGrr"/>
+        <phase duration="2" state="yyrr"/>
+        <phase duration="42" state="rrGG"/>
+        <phase duration="2" state="rryy"/>
+    </tlLogic>
+
+    <junction id="e" type="dead_end" x="300.00" y="150.00" incLanes="t_e_0 t_e_1" intLanes="" shape="300.00,143.45 300.00,149.95"/>
+    <junction id="n" type="dead_end" x="150.00" y="300.00" incLanes="" intLanes="" shape="149.95,300.00 143.45,300.00"/>
+    <junction id="s" type="dead_end" x="150.00" y="0.00" incLanes="t_s_0 t_s_1" intLanes="" shape="143.45,0.00 149.95,0.00"/>
+    <junction id="t" type="traffic_light" x="150.00" y="150.00" incLanes="n_t_0 n_t_1 w_t_0 w_t_1" intLanes=":t_0_0 :t_0_1 :t_2_0 :t_2_1" shape="143.45,151.45 149.95,151.45 151.45,149.95 151.45,143.45 149.95,141.95 143.45,141.95 141.95,143.45 141.95,149.95">
+        <request index="0" response="1100" foes="1100" cont="0"/>
+        <request index="1" response="1100" foes="1100" cont="0"/>
+        <request index="2" response="0000" foes="0011" cont="0"/>
+        <request index="3" response="0000" foes="0011" cont="0"/>
+    </junction>
+    <junction id="w" type="dead_end" x="0.00" y="150.00" incLanes="" intLanes="" shape="0.00,149.95 0.00,143.45"/>
+
+    <connection from="n_t" to="t_s" fromLane="0" toLane="0" via=":t_0_0" tl="t" linkIndex="0" dir="s" state="o"/>
+    <connection from="n_t" to="t_s" fromLane="1" toLane="1" via=":t_0_1" tl="t" linkIndex="1" dir="s" state="o"/>
+    <connection from="w_t" to="t_e" fromLane="0" toLane="0" via=":t_2_0" tl="t" linkIndex="2" dir="s" state="o"/>
+    <connection from="w_t" to="t_e" fromLane="1" toLane="1" via=":t_2_1" tl="t" linkIndex="3" dir="s" state="o"/>
+
+    <connection from=":t_0" to="t_s" fromLane="0" toLane="0" dir="s" state="M"/>
+    <connection from=":t_0" to="t_s" fromLane="1" toLane="1" dir="s" state="M"/>
+    <connection from=":t_2" to="t_e" fromLane="0" toLane="0" dir="s" state="M"/>
+    <connection from=":t_2" to="t_e" fromLane="1" toLane="1" dir="s" state="M"/>
+
+</net>