gepa-spo/dist/judge.js

Genetic-Pareto prompt optimizer to evolve system prompts from a few rollouts with modular support and intelligent crossover

import { clampNumber, safeParseWithSchema } from './json.js';
export function buildJudgePrompt(rubric) {
    return [
        'You are a strict evaluator. Return ONLY JSON: {"score":0.00,"feedback":"..."}',
        'Score in [0,1] with two decimals. Keep feedback brief.',
        'Rubric:', rubric
    ].join('\n');
}
/** Call the judge LLM to evaluate system+user+assistant => {score, feedback} */
export async function judgeScore(chatLLM, rubric, system, user, assistant) {
    const sys = buildJudgePrompt(rubric);
    const content = await chatLLM.chat([
        { role: 'system', content: sys },
        { role: 'user', content: `System:\n${system}\n\nUser:\n${user}\n\nAssistant:\n${assistant}` }
    ]);
    // Structured parse with clamping and defaults
    const schema = {
        parse(input) {
            const o = (typeof input === 'object' && input) ? input : {};
            const score = clampNumber(o.score, 0, 1, 0);
            const feedback = typeof o.feedback === 'string' ? o.feedback : '';
            return { score, feedback };
        }
    };
    const parsed = safeParseWithSchema(content, schema);
    return parsed;
}