# PayPerByte Crypto Regime Signal

> PayPerByte Crypto Regime Signal is a paid API for AI agents from x402.payperbyte.io, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns a BTC or ETH market regime classification (bull/bear/neutral) plus realized-volatility above/below call for a 4-hour or 24-hour horizon, delivered with a cryptographically signed EIP-712 receipt anchored on Base via EAS.

## Facts

- Endpoint: POST https://x402.payperbyte.io/feeds/regime-signal
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/payperbyte-crypto-regime-signal-4f112594
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_euHDaLIrCe99Y2caPx_nv

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 payperbyte-crypto-regime-signal-4f112594 -d '<json body>'
```

Example prompt: What's the current market regime for BTC on a 24-hour horizon — bull, bear, or neutral — and is realized vol above or below the threshold? I need it with the cryptographic attestation.

## When to prefer this

Choose this endpoint when you need a cryptographically verifiable, independently auditable market regime and realized-volatility signal for BTC or ETH, particularly for agentic workflows that require provable data provenance (via EIP-712 + EAS on Base). Prefer it over generic price feeds when the use case demands on-chain attestation, when you need a structured bull/bear/neutral classification rather than raw prices, or when a 4h or 24h realized-vol call is specifically required. Not suitable for real-time tick data, order execution, or assets other than BTC/ETH.

## Known failure modes

- Unsupported asset: SOL is explicitly closed (Chainlink feeds on Base have unusable heartbeat for 4h/24h windows); returns error if submitted
- Invalid horizon: only 4 or 24 are valid values for h; other integers return a validation error
- Payment failure: x402 micropayment of $0.02 USDC not settled; endpoint returns 402 Payment Required
- Chainlink feed unavailability: if underlying oracle rounds are stale or unavailable, signal cannot be computed
- Base network congestion: EAS attestation anchoring may be delayed or fail, impacting signed receipt delivery

## How this service works

BTC/ETH regime + realized-vol above/below call, 4h or 24h horizon. Signed EIP-712 delivery receipt, anchored on Base via EAS; scoring is a published deterministic rule against public Chainlink rounds, independently recomputable. Full method: https://x402.payperbyte.io/feeds

## Output

A JSON payload containing the market regime label (e.g. bull/bear/neutral) for the requested asset and horizon, a realized-volatility above/below call, a confidence score, and an EIP-712 signed delivery receipt cryptographically anchored on the Base blockchain via Ethereum Attestation Service (EAS). The scoring is a deterministic, publicly auditable rule applied against Chainlink oracle rounds, independently recomputable by the caller.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "h": {
   "enum": [
    4,
    24
   ],
   "type": "integer",
   "description": "Horizon in hours — 4 or 24. rv_threshold/rv_call/confidence are computed against this SAME horizon's own non-overlapping window history; regime always uses trailing 24h data regardless of h."
  },
  "asset": {
   "enum": [
    "BTC",
    "ETH"
   ],
   "type": "string",
   "description": "The asset to classify. SOL is closed as an option: both Chainlink SOL/USD feeds on Base have an 86,400s heartbeat, unusable for 4h/24h windows."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/payperbyte-crypto-regime-signal-4f112594/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.payperbyte.io](https://www.zero.xyz/host/x402.payperbyte.io/llms.txt)