eval/evaluators.py

from phoenix.evals import create_evaluator

@create_evaluator(name="conciseness_evaluator")
def conciseness_evaluator(output: str, expected: str):
    ratio = (len(output) / len(expected))
    if ratio < 0.5:
        return "too short"
    elif ratio > 3.0:
        return "too long"
    else:
        return "concise"