# MatrixFold Social Post Validator

> MatrixFold Social Post Validator is a paid API for AI agents from api-production-853c.up.railway.app, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Validates X/Twitter, LinkedIn, and Xiaohongshu posts for platform compliance before publishing, returning rule codes, risk score, and suggested fixes.

## Facts

- Endpoint: POST https://api-production-853c.up.railway.app/v1/validate
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-production-853c-up-railway-app-7ca958a5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vNRsszKUu3RtehmeYHSCP

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 api-production-853c-up-railway-app-7ca958a5 -d '<json body>'
```

Example prompt: Before I post this on LinkedIn, can you run a compliance check on it: 'Excited to announce our new product launch! Contact me at john@gmail.com or WhatsApp +1-555-0123. Follow for updates! #hiring #startup #tech #innovation #growth #linkedin #networking #B2B #entrepreneur #CEO' — flag any rule violations, give me a risk score, and tell me what to fix.

## When to prefer this

Use this endpoint when an AI agent needs to pre-screen social media posts for X/Twitter, LinkedIn, or Xiaohongshu before publishing — especially to catch platform-specific rule violations like hashtag limits, emoji density, off-platform contact scraping terms, link restrictions, and character length. Prefer this over generic text analysis when you need platform-specific rule codes and risk scoring rather than sentiment or readability.

## Known failure modes

- Missing or unsupported platform identifier returns an error
- Post text field empty or null causes validation failure
- Network timeout from Railway hosting environment
- Malformed JSON request body returns 400-level error
- Payment not processed (x402 protocol failure) blocks the call

## Output

A JSON object containing rule violation codes (e.g. excessive hashtags, off-platform contact detected, length exceeded), a numeric risk score, and actionable fix suggestions for each violation found in the post.

## Example request

```json
{
 "text": "Excited to announce our new product launch! We're committed to delivering innovative solutions for our customers. Follow for updates! #startup #tech #innovation",
 "platform": "x"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-production-853c-up-railway-app-7ca958a5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api-production-853c.up.railway.app](https://www.zero.xyz/host/api-production-853c.up.railway.app/llms.txt)