# PerCall Momentum Signals

> PerCall Momentum Signals is a paid API for AI agents from percall.kimi.pro, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Returns a cross-pair momentum score (-100 to +100) with regime label for the top 10 USDT pairs, computed from 7 days of hourly closes, including 24h/7d rate-of-change, realised volatility, and composite ranking.

## Facts

- Endpoint: GET https://percall.kimi.pro/api/x402/signals/momentum
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/percall-momentum-signals-995c308e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dxf73PNwRBa90ucbmO2re

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 percall-momentum-signals-995c308e
```

Example prompt: Give me the current momentum scores and regime labels for the top USDT pairs — I want to see which ones are trending up versus ranging before I place any trades.

## When to prefer this

Choose this endpoint when you need a pre-computed, multi-factor momentum ranking across the top USDT pairs rather than raw price data for a single pair. It is ideal for pre-trade screening, portfolio rotation logic, or regime-aware strategies where you want a composite score blending ROC and volatility in a single call. Prefer it over raw price or order book endpoints when the agent needs to make a relative ranking decision across pairs rather than act on a single instrument.

## Known failure modes

- Payment failure (402): x402 micropayment of $0.01 USDC not completed or invalid
- Upstream data unavailable: exchange data feed disruption may result in stale or missing signals
- Empty signals array: if fewer than 10 pairs have sufficient data for the 7-day lookback
- Rate limiting: excessive calls in a short window may be throttled
- Malformed response if internal computation fails due to insufficient historical data

## How this service works

PerCall is an x402 payment gateway selling live crypto market data to AI agents and developers. No accounts, no API keys: request, receive HTTP 402, pay in USDC on Base, get data.

## Output

A JSON object containing a ranked list of up to 10 USDT trading pairs, each with: composite momentum score (-100 to +100), regime label (TRENDING_UP, TRENDING_DOWN, or RANGING), 24h and 7d rate-of-change percentages, 7-day realised volatility, and rank. Also includes metadata: lookback period, generation timestamp, and methodology description.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "required": {
   "type": "string"
  },
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "signals": [
   {
    "rank": 1,
    "score": 62.4,
    "regime": "TRENDING_UP",
    "symbol": "SOLUSDT",
    "roc7dPct": 11.87,
    "roc24hPct": 4.21,
    "volatility7dPct": 2.94
   }
  ],
  "lookback": "7d hourly closes",
  "generatedAt": "2026-08-28T00:00:00.000Z",
  "methodology": "score = z-scored blend of 24h ROC, 7d ROC and inverse realised volatility, rescaled to -100..100. regime: TRENDING_UP if score >= 25, TRENDING_DOWN if <= -25, else RANGING."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/percall-momentum-signals-995c308e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from percall.kimi.pro](https://www.zero.xyz/host/percall.kimi.pro/llms.txt)