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Reasoning Gym Environment

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Reasoning Gym Environment

An OpenEnv environment that integrates the Reasoning Gym library to provide single-step reasoning tasks. Each episode presents one question from a configurable dataset, the agent submits an answer, and receives a score.

Quick Start

The simplest way to use the Reasoning Gym environment is through the ReasoningGymEnv class:

from reasoning_gym_env import ReasoningGymAction, ReasoningGymEnv

try:
    # Create environment from Docker image
    env = ReasoningGymEnv.from_docker_image("reasoning_gym-env:latest").sync()

    # Create a dataset with 10 leg_counting questions
    result = env.reset(
        dataset_name='leg_counting',
        seed=42,
        size=10
    )
    print(f"Question: {result.observation.question}")
    # Question: "How many legs does a cat have?"

    # Submit answer
    result = env.step(ReasoningGymAction(answer="4"))
    print(f"Score: {result.observation.score}")  # 1.0 (correct)
    print(f"Correct answer: {result.observation.correct_answer}")  # "4"
    print(f"Reward: {result.reward}")  # 1.0
    print(f"Done: {result.done}")  # True (single-step episodes)

    # Access dataset metadata if available
    if result.observation.dataset_metadata:
        print(f"Metadata: {result.observation.dataset_metadata}")  # Dataset-specific info

    # Get next question from same dataset
    result = env.reset()  # No params = reuse dataset
    print(f"Next question: {result.observation.question}")

    # Note: First reset() without params creates a default leg_counting dataset
    # with seed=42 and size=1000 for reproducible, out-of-the-box functionality

finally:
    # Always clean up
    env.close()

That’s it! The ReasoningGymEnv.from_docker_image() method handles:

Starting the Docker container
Waiting for the server to be ready
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 the reasoning_gym_env directory
docker build -t reasoning_gym-env:latest -f server/Dockerfile .

Deploying to Hugging Face Spaces

From envs/reasoning_gym_env/, run openenv push (or openenv push --repo-id my-org/reasoning-gym-env). See the openenv push reference for all options. The Space serves the web UI at /web, the API docs at /docs, a health check at /health and the WebSocket session endpoint at /ws.

Environment Details

Episode Structure

Each episode is single-step:

reset() returns a question
step(answer) returns score and marks episode as done
reset() without params gets next question from same dataset

Action

ReasoningGymAction: Contains the agent’s answer

answer (str) - The agent’s answer to the current question

Observation

ReasoningGymObservation: Contains the question or result

question (Optional[str]) - The current question (only in reset)
score (Optional[float]) - Score for the answer, 0.0 to 1.0 (only after step)
correct_answer (Optional[str]) - The correct answer (only after step)
dataset_metadata (Optional[Dict]) - Metadata from the reasoning gym dataset entry
done (bool) - Always True after step (single-step episodes)
reward (float) - Equal to score (0.0 to 1.0)

Reward

The reward equals the score returned by the dataset’s scoring function:

Correct answer → score: 1.0
Incorrect answer → score: 0.0 to 1.0 (dataset-dependent, may use partial credit)

Dataset Configuration

Simple Datasets

Use a single dataset with configuration:

result = env.reset(
    dataset_name='leg_counting',
    seed=42,
    size=10
)

Available datasets from reasoning_gym library:

leg_counting - Count legs of various objects
reverse_sort - Sort lists in reverse order
chess_state_eval - Chess position evaluation
And more (see Reasoning Gym documentation)

Composite Datasets

Mix multiple datasets with custom weights:

result = env.reset(
    dataset_name='composite',
    dataset_specs=[
        {
            "name": "leg_counting",
            "weight": 3,  # 3x more likely
            "config": {}
        },
        {
            "name": "reverse_sort",
            "weight": 1,
            "config": {"min_length": 3, "max_length": 5}
        }
    ],
    seed=42,
    size=20
)

Dataset Persistence

The dataset persists across resets until configuration changes:

# Create dataset
result = env.reset(dataset_name='leg_counting', seed=42, size=10)
question1 = result.observation.question

# Get next question from SAME dataset
result = env.reset()  # No params = reuse dataset
question2 = result.observation.question

# Create NEW dataset (different seed)
result = env.reset(dataset_name='leg_counting', seed=99, size=10)
question3 = result.observation.question  # From new dataset

Advanced Usage

Connecting to an Existing Server

If you already have a Reasoning Gym environment server running, you can connect directly:

from reasoning_gym_env import ReasoningGymEnv, ReasoningGymAction

# Connect to existing server
env = ReasoningGymEnv(base_url="http://localhost:8000")

# Use as normal
result = env.reset(
    dataset_name='leg_counting',
    dataset_config={"min_animals": 5, "max_animals": 15}
    seed=42,
    size=10
)
result = env.step(ReasoningGymAction(answer="4"))

Note: When connecting to an existing server, env.close() will NOT stop the server.

Using the Context Manager

The client supports context manager usage for automatic connection management:

from reasoning_gym_env import ReasoningGymAction, ReasoningGymEnv

# Connect with context manager (auto-connects and closes)
with ReasoningGymEnv(base_url="http://localhost:8000") as env:
    result = env.reset(
        dataset_name='leg_counting',
        seed=42,
        size=5
    )
    print(f"Question: {result.observation.question}")

    # Multiple steps with low latency
    for i in range(5):
        result = env.step(ReasoningGymAction(answer="4"))
        print(f"Score: {result.observation.score}")
        if result.done:
            result = env.reset()  # Get next question

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 is configured to support multiple concurrent WebSocket connections:

from reasoning_gym_env import ReasoningGymAction, ReasoningGymEnv
from concurrent.futures import ThreadPoolExecutor

def run_episode(client_id: int):
    with ReasoningGymEnv(base_url="http://localhost:8000") as env:
        result = env.reset(
            dataset_name='leg_counting',
            seed=42 + client_id,  # Different seed per client
            size=10
        )
        total_score = 0.0
        for i in range(10):
            result = env.step(ReasoningGymAction(answer="4"))
            total_score += result.observation.score
            if result.done:
                result = env.reset()  # Next question
        return client_id, total_score

# Run 4 episodes concurrently
with ThreadPoolExecutor(max_workers=4) as executor:
    results = list(executor.map(run_episode, range(4)))
    for client_id, score in results:
        print(f"Client {client_id}: Total score = {score}")

Development & Testing

Direct Environment Testing

Test the environment logic directly without starting the HTTP server:

# From the reasoning_gym_env directory
python3 server/reasoning_gym_environment.py

This verifies that:

Environment resets correctly
Step executes actions properly
Dataset creation and iteration works
Scoring is calculated correctly

Running Locally

Run the server locally for development:

# From the reasoning_gym_env directory
uvicorn server.app:app --reload

Then test with:

from reasoning_gym_env import ReasoningGymEnv, ReasoningGymAction

env = ReasoningGymEnv(base_url="http://localhost:8000")
result = env.reset(dataset_name='leg_counting', seed=42, size=5)
print(result.observation.question)

Use Cases

The Reasoning Gym environment is ideal for:

LLM Evaluation: Benchmark reasoning capabilities across diverse tasks
Agent Training: Train RL agents on reasoning tasks with clear score signals
Curriculum Learning: Mix datasets with composite configurations for progressive difficulty
Research: Reproducible environments with seed control for scientific experiments
Educational: Learn about environment design and agent-environment interaction

Learn More

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