# PQS: Prompt Quality Score – Batch Scoring

> PQS: Prompt Quality Score – Batch Scoring is a paid API for AI agents from api.relai.fi, paid per call via x402, $0.25/call, status unknown (last checked 2026-09-14).

Score a batch of 1–10 prompts for quality using the PQS (Prompt Quality Score) API, optionally tagged by vertical, via Solana x402 payment.

## Facts

- Endpoint: GET https://api.relai.fi/relay/1779373065272/api/score/batch/sol
- Price: $0.25/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pqs-prompt-quality-score-batch-scoring-a68b8df3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nk-CMfq-riUSKgkivkgUc

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 pqs-prompt-quality-score-batch-scoring-a68b8df3
```

Example prompt: Can you score the quality of these three prompts for me — 'Summarize this article in bullet points', 'Write me a poem', and 'Explain quantum entanglement to a 10-year-old' — treating them as general vertical prompts?

## When to prefer this

Use this endpoint when you need to evaluate and rank prompt quality for multiple prompts at once (up to 10), especially when you want domain-specific scoring by vertical (software, content, business, education, science, crypto, general, research). Prefer over single-prompt evaluation when processing batches to minimize cost and latency.

## Known failure modes

- Empty prompts array or array exceeding 10 items returns validation error
- Prompt text exceeding 10,000 characters rejected
- Invalid vertical enum value causes schema validation failure
- Payment failure on Solana x402 returns 402 Payment Required
- Malformed request body returns 400 Bad Request
- Service unavailable returns 500 or timeout

## How this service works

Batch PQS scoring (Solana x402)

## Output

Returns PQS (Prompt Quality Score) ratings for each submitted prompt, indicating how well-formed and effective each prompt is likely to be for its intended purpose.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "prompts": {
   "type": "array",
   "items": {
    "oneOf": [
     {
      "type": "string",
      "maxLength": 10000,
      "minLength": 1
     },
     {
      "type": "object",
      "required": [
       "prompt"
      ],
      "properties": {
       "prompt": {
        "type": "string",
        "maxLength": 10000,
        "minLength": 1
       },
       "vertical": {
        "enum": [
         "software",
         "content",
         "business",
         "education",
         "science",
         "crypto",
         "general",
         "research"
        ],
        "type": "string"
       }
      }
     }
    ]
   },
   "maxItems": 10,
   "minItems": 1,
   "description": "Array of 1-10 prompts. Each item is a string or {prompt, vertical} object."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pqs-prompt-quality-score-batch-scoring-a68b8df3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relai.fi](https://www.zero.xyz/host/api.relai.fi/llms.txt)