haiku.rag/tests/llm_judge.py
2025-07-19 19:02:47 +03:00

81 lines
2.7 KiB
Python

import json
from ollama import AsyncClient
from pydantic import BaseModel
from haiku.rag.config import Config
class LLMJudgeResponseSchema(BaseModel):
equivalent: bool
class LLMJudge:
"""LLM-as-judge for evaluating answer equivalence using Ollama."""
def __init__(self, model: str = "qwen3"):
self.model = model
self.client = AsyncClient(host=Config.OLLAMA_BASE_URL)
async def judge_answers(
self, question: str, answer: str, expected_answer: str
) -> bool:
"""
Judge whether two answers are equivalent for a given question.
Args:
question: The original question
answer: The generated answer to evaluate
expected_answer: The reference/expected answer
Returns:
Dictionary with judgment result:
- equivalent: bool indicating if answers are equivalent
- explanation: str explaining the reasoning
- score: str rating from 1-5
"""
prompt = f"""You are an expert evaluator determining whether two answers to the same question are semantically equivalent.
QUESTION: {question}
GENERATED ANSWER: {answer}
EXPECTED ANSWER: {expected_answer}
EVALUATION CRITERIA:
Rate as EQUIVALENT (true) if:
✓ Both answers contain the same core factual information
✓ Both directly address the question asked
✓ The key claims and conclusions are consistent
✓ Any additional detail in one answer doesn't contradict the other
Rate as NOT EQUIVALENT (false) if:
✗ Factual contradictions exist between the answers
✗ One answer fails to address the core question
✗ Key information is missing from one answer that changes the meaning
✗ The answers lead to different conclusions or implications
GUIDELINES:
- Ignore minor differences in phrasing, style, or formatting
- Focus on semantic meaning rather than exact wording
- Consider both answers correct if they convey the same essential information
- Be tolerant of different levels of detail if the core answer is preserved
- Evaluate based on what a person asking this question would need to know
Respond with JSON containing only: {{"equivalent": true}} or {{"equivalent": false}}"""
response = await self.client.chat(
model=self.model,
messages=[{"role": "user", "content": prompt}],
format=LLMJudgeResponseSchema.model_json_schema(),
think=False,
)
answer = response["message"]["content"].strip()
try:
res = json.loads(answer)
assert "equivalent" in res, "Response must contain 'equivalent' key"
return res["equivalent"]
except json.JSONDecodeError:
assert False, "Response is not valid JSON"