# Ai for 500 Market Check

> Ai for 500 Market Check is a paid API for AI agents from aifor500.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-14).

Returns evidence-backed market intelligence (assessment, confidence score, and usage signals) for a product or offer in the AI-agent economy

## Facts

- Endpoint: POST https://aifor500.com/api/market-check.php
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ai-for-500-market-check-a37bd223
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9IuCBs8ZRHvdLumgNE98-

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 ai-for-500-market-check-a37bd223 -d '<json body>'
```

Example prompt: Can you run a market check on my idea for an AI-powered contract review tool targeted at small law firms — I want to know if there's real evidence of demand and how competitive the space is before I put serious resources into it?

## When to prefer this

Choose this endpoint when you need a fast, quantitative market signal grounded in actual usage and payer data for the AI-agent economy specifically — not general web sentiment or survey data. It is especially useful for pre-launch validation, resource allocation decisions, and competitive scoping within the agent/AI tooling space. Prefer it over generic market research APIs when you want a scored, evidence-backed go/no-go output with explicit confidence framing.

## Known failure modes

- Insufficient market data for a very novel or narrow niche may yield low evidence coverage and a low confidence score
- Vague or overly broad product descriptions may produce less actionable assessments
- Payment failure (insufficient USDC balance or x402 protocol error) will prevent the request from completing
- Rate limiting or service unavailability may return non-200 responses

## How this service works

Ai for 500 provides evidence-backed market intelligence for the emerging AI-agent economy. Market Check costs $0.05 USDC per request through x402.

## Output

A JSON object containing: a plain-English summary recommendation, an assessment label (e.g. GO, WATCH, STOP), a confidence score (0–1) reflecting evidence sufficiency, a numeric decision score (0–100), tracked competitor count, median call volume over 30 days, median payer signal over 30 days, and usage evidence coverage percentage.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "product": "Ai for 500 Market Check",
  "success": true,
  "summary": "Current evidence is mixed. Validate a narrower offer before committing significant resources.",
  "evidence": {
   "median_calls_30d": 3,
   "tracked_competitors": 13,
   "median_payer_signal_30d": 1,
   "usage_evidence_coverage_pct": 100
  },
  "price_usd": "0.05",
  "assessment": "WATCH",
  "confidence": 0.92,
  "decision_score": 60,
  "confidence_meaning": "evidence sufficiency, not success probability"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ai-for-500-market-check-a37bd223/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from aifor500.com](https://www.zero.xyz/host/aifor500.com/llms.txt)