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APPS Coding Example

This guide explains how to use the reward-kit run command to evaluate code generation models on a sample of the codeparrot/apps dataset. This example focuses on checking the parsability of generated Python code.

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Overview

  • Dataset: A sample from codeparrot/apps, a dataset of programming problems and solutions. The specific dataset configuration used is apps_full_prompts (defined in conf/dataset/apps_full_prompts.yaml), which typically points to a pre-generated JSONL file.
  • Task: Given a problem description (question), the model should generate a Python code solution.
  • Reward Function: The evaluation uses reward_kit.rewards.apps_coding_reward.evaluate_apps_solution.
    • Functionality: In its current form for this example, this reward function performs a basic check to see if the generated Python code is parsable by Python’s ast.parse module. It scores 1.0 if the code is parsable and 0.0 otherwise.
    • It does not execute the code or check for functional correctness against test cases in this simplified setup.
    • The ground_truth_for_eval field (derived from APPS’ input_output field) is available to the reward function but not utilized by this initial parsability check.
  • System Prompt: A default system prompt is provided in the configuration to guide the model: 
    Please write a Python script that solves the following problem. Structure your solution within a main() function. Please read from stdin directly and make sure the code is not interactive. The main() function should print the final result(s) to standard output as required by the problem statement.

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Setup

  1. Environment: Ensure your Python environment is set up with reward-kit and its development dependencies installed. If you haven’t already, install them from the root of the repository: 
    pip install -e ".[dev]"
  2. API Key: The default configuration uses a Fireworks AI model (accounts/fireworks/models/deepseek-v3-0324) for code generation. Make sure your FIREWORKS_API_KEY is set in your environment or in a .env file in the project root.

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Data Preparation (Informational)

The example typically uses a pre-generated sample of prompts from the codeparrot/apps dataset. The default run configuration (run_eval.yaml) references apps_full_prompts, which points to development/CODING_DATASET.jsonl. If you wished to regenerate this sample or create a different one (this is for informational purposes, not required to run the example with defaults):
  1. The script scripts/convert_apps_to_prompts.py can convert the raw Hugging Face codeparrot/apps dataset into the JSONL format expected by the pipeline.
  2. The source dataset configuration for raw APPS data is defined in conf/dataset/apps_source.yaml.
  3. An example command to generate 5 samples from the ‘test’ split: 
    python scripts/convert_apps_to_prompts.py \
    --dataset_name codeparrot/apps \
    --split test \
    --output_file development/apps_sample_prompts.jsonl \
    --max_samples 5 \
    --id_column problem_id \
    --query_column question \
    --ground_truth_column input_output

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Running the Evaluation

The evaluation is configured in examples/apps_coding_example/conf/run_eval.yaml. This is the main configuration file used by Hydra. To run the evaluation using the reward-kit run command:
  1. Ensure your virtual environment is activated: 
    source .venv/bin/activate
  2. Execute the run command from the root of the repository: 
    reward-kit run --config-path examples/apps_coding_example/conf --config-name run_eval

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Overriding Parameters

You can override parameters from the run_eval.yaml configuration directly from the command line. For example:
  • Limit the number of samples for a quick test: 
    reward-kit run --config-path examples/apps_coding_example/conf --config-name run_eval evaluation_params.limit_samples=2
  • Disable code generation (to test reward function with cached responses): If you have previously run the example and responses are cached (default cache dir: outputs/generated_responses_cache_apps/), you can disable new generation: 
    reward-kit run --config-path examples/apps_coding_example/conf --config-name run_eval generation.enabled=false
  • Change the generation model: 
    reward-kit run --config-path examples/apps_coding_example/conf --config-name run_eval generation.model_name="accounts/fireworks/models/another-model"
Refer to the Hydra Configuration for Examples guide for more details on Hydra.

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Expected Output

The reward-kit run command will:
  1. Load prompts based on the apps_full_prompts dataset configuration (typically from development/CODING_DATASET.jsonl).
  2. If generation.enabled is true (default), generate code solutions using the configured model. Responses are cached (default: outputs/generated_responses_cache_apps/).
  3. Evaluate each generated solution using the evaluate_apps_solution reward function (checking for Python AST parsability).
  4. Print a summary of results to the console.
  5. Save detailed evaluation results to a JSONL file in a timestamped directory. The default output path is configured in run_eval.yaml as ./outputs/apps_coding_example/${now:%Y-%m-%d}/${now:%H-%M-%S}. The results file will be named apps_coding_example_results.jsonl within that directory.
The results file will contain the original prompt, generated response, the parsability score (0 or 1), and other metrics from the reward function.