title: Code Output Assessment Environment
emoji: π§ͺ
colorFrom: purple
colorTo: pink
sdk: docker
pinned: false
app_port: 8000
base_path: /web
tags:
- openenv
- code-assessment
- rl-environment
- code-grading
Code Output Assessment Environment
An OpenEnv RL environment that tests an agent's ability to solve coding problems across three difficulty levels with automated grading and shaped rewards.
Overview
This environment challenges AI agents to:
- Solve coding problems at varying difficulty levels (Easy, Medium, Hard)
- Produce correct outputs for given test cases
- Maximize rewards through accuracy and maintaining solving streaks
Difficulty Levels
π’ Easy (1x multiplier)
- Basic arithmetic operations (addition, max)
- Simple string manipulation (reversal, vowel counting)
- Example: Add two numbers:
3,5β8
π‘ Medium (2x multiplier)
- String/list processing (palindrome check, duplicate removal)
- Aggregation operations (sum of lists, character counting)
- Example: Check palindrome:
racecarβtrue
π΄ Hard (5x multiplier)
- Advanced algorithms (Fibonacci, prime numbers)
- Complex logic (balanced parentheses, longest word)
- Example: Find primes up to n:
10β2,3,5,7
Grading & Reward System
Normalized Grading (0.0-1.0)
All graders produce normalized scores regardless of difficulty:
| Score Range | Meaning | Feedback |
|---|---|---|
| 1.0 | Perfect answer | "β Correct!" |
| 0.8-0.9 | Very close | "β‘ Very close! 80-90% correct" |
| 0.5-0.7 | Moderate partial credit | "β‘ Partial credit: 50-70% correct" |
| 0.2-0.4 | Low partial credit | "β‘ Some correct elements" |
| 0.1 | Format credit only | "β‘ Correct format, wrong values" |
| 0.0 | Completely wrong | "β Incorrect" |
Reward Calculation
Formula: reward = grader_score Γ difficulty_multiplier + bonuses
| Difficulty | Multiplier | Perfect (1.0) | High Partial (0.7) | Low Partial (0.3) | Wrong (0.0) |
|---|---|---|---|---|---|
| Easy | 1x | +1.0 | +0.35 | +0.15 | 0.0 |
| Medium | 2x | +2.0 | +1.4 | +0.6 | 0.0 |
| Hard | 5x | +5.0 | +3.5 | +1.5 | -0.3 |
Bonuses:
- Streak Bonus: +0.5 for maintaining 3+ consecutive correct answers
- Penalty: -0.3 on hard problems for completely wrong answers (discourages random guessing)
Maximum Episode Reward: ~28.0 (perfect accuracy with streaks)
Quick Start
The simplest way to use the Code Assessment environment is through the CodeAssessmentEnv class:
from code_assessment_env import CodeAssessmentAction, CodeAssessmentEnv
# Create environment from Docker image
env = CodeAssessmentEnv.from_docker_image("code_assessment_env:latest").sync()
# Reset to get first problem
result = env.reset()
print(f"Problem: {result.observation.problem_description}")
print(f"Difficulty: {result.observation.difficulty}")
print(f"Test Input: {result.observation.test_case_input}")
# Submit an answer
result = env.step(CodeAssessmentAction(answer="8"))
print(f"Correct: {result.observation.is_correct}")
print(f"Reward: {result.reward}")
print(f"Feedback: {result.observation.feedback}")
# Continue solving problems
for _ in range(10):
obs = result.observation
# Your agent logic here to solve obs.problem_description with obs.test_case_input
answer = solve_problem(obs.problem_description, obs.test_case_input)
result = env.step(CodeAssessmentAction(answer=answer))
if result.done:
break
env.close()
Key Features
β Normalized Grading System
Each answer is graded on a 0.0-1.0 scale:
- Exact match detection: Full credit (1.0)
- Partial credit: 0.1-0.9 based on correctness percentage
- Format validation: Credit for proper structure even if values are wrong
- String similarity: Grading for text-based answers using overlap metrics
β Difficulty-Scaled Rewards
- Normalized grader scores (0.0-1.0) are multiplied by difficulty
- Easy: 1x, Medium: 2x, Hard: 5x multipliers
- Higher difficulty = higher potential rewards for correct answers
- Partial credit proportionally scaled by difficulty
β Progressive Difficulty
- Starts with Easy problems
- Advances to Medium after solving 4 problems
- Advances to Hard after solving 8 problems
β Shaped Rewards
- Base rewards scale with difficulty
- Partial credit for near-correct answers
- Streak bonuses for consecutive successes
- Penalties for repeated failures on hard problems
β Rich Feedback
Observations include:
problem_description: What to solvedifficulty: Current difficulty leveltest_case_input: Input to processfeedback: Grading feedback ("β Correct!", "β Incorrect", etc.)is_correct: Boolean correctness flagpartial_credit: Score between 0.0-1.0problems_solved: Total solved countcurrent_streak: Consecutive correct answers
Running with LLM Agent
Use the included inference script to test with an LLM:
# Set environment variables
export IMAGE_NAME=code_assessment_env:latest
export HF_TOKEN=your_huggingface_token
# Run inference
uv run python inferency.py
Expected output:
[START] task=code_output_assessment env=code_assessment_env model=Qwen/Qwen2.5-72B-Instruct
[STEP] step=1 action=answer='8' | correct=True | difficulty=easy reward=1.00 done=false error=null
[STEP] step=2 action=answer='olleh' | correct=True | difficulty=easy reward=1.00 done=false error=null
...
[END] success=true steps=15 score=0.720 rewards=1.00,1.00,2.00,2.00,5.00,...
Development
Building the Docker Image
cd code_assessment_env
docker build -t code_assessment_env:latest .
Running Locally
# Start the server
docker run -p 8000:8000 code_assessment_env:latest
# Test with API
curl http://localhost:8000/docs # Swagger UI
API Endpoints
POST /reset- Start new episodePOST /step- Submit answerGET /state- Get episode stateGET /schema- Get action/observation schemasGET /health- Health checkGET /docs- Interactive API documentation
Problem Examples
Easy Problems
# Addition
Input: "3,5" β Output: "8"
# String Reversal
Input: "hello" β Output: "olleh"
# Vowel Counting
Input: "hello" β Output: "2"
Medium Problems
# Palindrome Check
Input: "racecar" β Output: "true"
# Sum List
Input: "1,2,3" β Output: "6"
# Remove Duplicates
Input: "1,2,2,3" β Output: "1,2,3"
Hard Problems
# Fibonacci
Input: "10" β Output: "55"
# Balanced Parentheses
Input: "({[]})" β Output: "true"
# Prime Numbers
Input: "20" β Output: "2,3,5,7,11,13,17,19"
Training Tips
- Start Simple: Master easy problems before advancing
- Pay Attention to Format: Exact formatting matters (lowercase true/false, comma-separated lists)
- Build Streaks: Maintain accuracy for streak bonuses
- Learn from Feedback: Use partial credit signals to improve
- Optimize for Speed: Solve quickly to maximize problems per episode
License
BSD-style license - see LICENSE file for details.
- Connecting to the environment
- Container cleanup when you call
close()
Building the Docker Image
Before using the environment, you need to build the Docker image:
# From project root
docker build -t first_rl_proj-env:latest -f server/Dockerfile .
Deploying to Hugging Face Spaces
You can easily deploy your OpenEnv environment to Hugging Face Spaces using the openenv push command:
# From the environment directory (where openenv.yaml is located)
openenv push
# Or specify options
openenv push --namespace my-org --private
The openenv push command will:
- Validate that the directory is an OpenEnv environment (checks for
openenv.yaml) - Prepare a custom build for Hugging Face Docker space (enables web interface)
- Upload to Hugging Face (ensuring you're logged in)
Prerequisites
- Authenticate with Hugging Face: The command will prompt for login if not already authenticated
Options
--directory,-d: Directory containing the OpenEnv environment (defaults to current directory)--repo-id,-r: Repository ID in format 'username/repo-name' (defaults to 'username/env-name' from openenv.yaml)--base-image,-b: Base Docker image to use (overrides Dockerfile FROM)--private: Deploy the space as private (default: public)
Examples
# Push to your personal namespace (defaults to username/env-name from openenv.yaml)
openenv push
# Push to a specific repository
openenv push --repo-id my-org/my-env
# Push with a custom base image
openenv push --base-image ghcr.io/meta-pytorch/openenv-base:latest
# Push as a private space
openenv push --private
# Combine options
openenv push --repo-id my-org/my-env --base-image custom-base:latest --private
After deployment, your space will be available at:
https://huggingface.co/spaces/<repo-id>
The deployed space includes:
- Web Interface at
/web- Interactive UI for exploring the environment - API Documentation at
/docs- Full OpenAPI/Swagger interface - Health Check at
/health- Container health monitoring - WebSocket at
/ws- Persistent session endpoint for low-latency interactions
Environment Details
Action
FirstRlProjAction: Contains a single field
message(str) - The message to echo back
Observation
FirstRlProjObservation: Contains the echo response and metadata
echoed_message(str) - The message echoed backmessage_length(int) - Length of the messagereward(float) - Reward based on message length (length Γ 0.1)done(bool) - Always False for echo environmentmetadata(dict) - Additional info like step count
Reward
The reward is calculated as: message_length Γ 0.1
- "Hi" β reward: 0.2
- "Hello, World!" β reward: 1.3
- Empty message β reward: 0.0
Advanced Usage
Connecting to an Existing Server
If you already have a First Rl Proj environment server running, you can connect directly:
from first_rl_proj import FirstRlProjEnv
# Connect to existing server
first_rl_projenv = FirstRlProjEnv(base_url="<ENV_HTTP_URL_HERE>")
# Use as normal
result = first_rl_projenv.reset()
result = first_rl_projenv.step(FirstRlProjAction(message="Hello!"))
Note: When connecting to an existing server, first_rl_projenv.close() will NOT stop the server.
Using the Context Manager
The client supports context manager usage for automatic connection management:
from first_rl_proj import FirstRlProjAction, FirstRlProjEnv
# Connect with context manager (auto-connects and closes)
with FirstRlProjEnv(base_url="http://localhost:8000") as env:
result = env.reset()
print(f"Reset: {result.observation.echoed_message}")
# Multiple steps with low latency
for msg in ["Hello", "World", "!"]:
result = env.step(FirstRlProjAction(message=msg))
print(f"Echoed: {result.observation.echoed_message}")
The client uses WebSocket connections for:
- Lower latency: No HTTP connection overhead per request
- Persistent session: Server maintains your environment state
- Efficient for episodes: Better for many sequential steps
Concurrent WebSocket Sessions
The server supports multiple concurrent WebSocket connections. To enable this,
modify server/app.py to use factory mode:
# In server/app.py - use factory mode for concurrent sessions
app = create_app(
FirstRlProjEnvironment, # Pass class, not instance
FirstRlProjAction,
FirstRlProjObservation,
max_concurrent_envs=4, # Allow 4 concurrent sessions
)
Then multiple clients can connect simultaneously:
from first_rl_proj import FirstRlProjAction, FirstRlProjEnv
from concurrent.futures import ThreadPoolExecutor
def run_episode(client_id: int):
with FirstRlProjEnv(base_url="http://localhost:8000") as env:
result = env.reset()
for i in range(10):
result = env.step(FirstRlProjAction(message=f"Client {client_id}, step {i}"))
return client_id, result.observation.message_length
# Run 4 episodes concurrently
with ThreadPoolExecutor(max_workers=4) as executor:
results = list(executor.map(run_episode, range(4)))
Development & Testing
Direct Environment Testing
Test the environment logic directly without starting the HTTP server:
# From the server directory
python3 server/first_rl_proj_environment.py
This verifies that:
- Environment resets correctly
- Step executes actions properly
- State tracking works
- Rewards are calculated correctly
Running Locally
Run the server locally for development:
uvicorn server.app:app --reload
Project Structure
first_rl_proj/
βββ .dockerignore # Docker build exclusions
βββ __init__.py # Module exports
βββ README.md # This file
βββ openenv.yaml # OpenEnv manifest
βββ pyproject.toml # Project metadata and dependencies
βββ uv.lock # Locked dependencies (generated)
βββ client.py # FirstRlProjEnv client
βββ models.py # Action and Observation models
βββ server/
βββ __init__.py # Server module exports
βββ first_rl_proj_environment.py # Core environment logic
βββ app.py # FastAPI application (HTTP + WebSocket endpoints)
βββ Dockerfile # Container image definition