# Agent402 Judge – LLM-as-Judge Evaluation Endpoint

> Agent402 Judge – LLM-as-Judge Evaluation Endpoint is a paid API for AI agents from agent402.tools, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-11).

Evaluates arbitrary content against custom question sets using LLM-as-a-judge, returning structured scores, choices, or classifications per question.

## Facts

- Endpoint: POST https://agent402.tools/v1/judge?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-judge-llm-as-judge-evaluation-endpoint-6a058861
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2aB9D98huuEhtSWhsCN6u

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agent402-judge-llm-as-judge-evaluation-endpoint-6a058861 -d '<json body>'
```

Example prompt: Judge this AI-generated summary against my two questions: first, 'Is the summary factually accurate?' as a score from 0–10 with criteria focusing on factual grounding, and second, 'Is the tone professional?' as a choice between yes/no — use jev-latest and here's the content: 'The Eiffel Tower was built in 1889 and stands 330 metres tall.'

## When to prefer this

Choose this endpoint when you need structured, multi-dimensional LLM evaluation of arbitrary content without managing an API key or subscription — ideal for automated eval pipelines, agent output grading, or content moderation where pay-per-call pricing is more cost-effective than a standing API plan. Prefer it over rolling your own judge prompt when you want consistent, versioned judge models (jev-latest/jev-preview) with a schema-enforced question format.

## Known failure modes

- state field exceeds 8000 characters — request rejected or truncated
- invalid model enum value — returns validation error
- malformed questions object (missing type, instructions, or criteria) — error response
- payment not settled (x402 / MPP flow incomplete) — 402 or auth failure
- ambiguous question types causing low-confidence or inconsistent judgments

## How this service works

Ask a typed question about any content and get an answer your code can branch on, not prose to parse. Send state (the content, a string or object) and questions (your own ids mapped to question objects); get back answers keyed by those ids. Three question types: choice (pick one of your named options: returns choice, probabilities per option and confidence), score (a position on levels you describe, lowest first: returns score as a fractional level index, probabilities per level index.

## Output

A structured JSON object containing per-question judgments keyed by the caller's own question IDs — each entry includes the question type result (a numeric score, a selected choice option, or a noul result), enabling automated downstream branching or reporting.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "enum": [
    "gpt-6-luna",
    "microsoft-decision-1",
    "jev-latest",
    "jev-preview"
   ],
   "type": "string",
   "description": "Which model answers first; the others are fallbacks. microsoft-decision-1 is Microsoft Decision-1, a model-backed judgment, not deterministic. Defaults to jev-latest."
  },
  "state": {
   "type": [
    "string",
    "object",
    "array"
   ],
   "description": "The content to judge. Up to 8000 characters."
  },
  "questions": {
   "type": "object",
   "description": "Your own ids mapped to question objects. Each has type (choice/score/noul), instructions, and criteria for choice/score."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-judge-llm-as-judge-evaluation-endpoint-6a058861/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.tools](https://www.zero.xyz/host/agent402.tools/llms.txt)