# Delx BTC Up/Down 15-Minute Probability

> Delx BTC Up/Down 15-Minute Probability is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-15).

Estimates the probability that Bitcoin's price will be up or down over a 15-minute window, given caller-supplied price observations and window parameters.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/bitcoin-up-down-15m
- 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/delx-btc-up-down-15-minute-probability-00883f95
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kDR914A1LkmGXMlz1lfgk

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 delx-btc-up-down-15-minute-probability-00883f95 -d '<json body>'
```

Example prompt: Using my last 20 BTC price observations (timestamps and prices from the past hour), estimate the probability that Bitcoin will be up or down over the next 15-minute window that opens at $67,250 and closes at Unix timestamp 1716300000 — and compare the model edge if the UP share is priced at $0.72 and the DOWN share at $0.28 with a 50 bps entry fee.

## When to prefer this

Choose this endpoint when you need a fast, stateless probability estimate for Bitcoin's 15-minute directional movement using your own supplied price observations, without requiring any live market data feed. It is especially useful for prediction market agents that need a model-edge comparison against published share prices and entry fees. Prefer it over generic ML inference endpoints when you want a structured, versioned BTC-specific probability output with calibration warnings and data quality scoring.

## Known failure modes

- Fewer than 8 or more than 240 observations causes validation rejection
- Missing required fields (window_open_price or window_close_timestamp) returns an error
- Observations with duplicate or out-of-order timestamps may degrade data quality score
- Share prices outside [0,1] or fee_bps outside [0,1000] return schema validation errors
- Payment not settled via x402 results in 402 Payment Required response
- Low-quality or noisy input data produces a low data_quality score with appropriate warnings

## How this service works

Bitcoin Up or Down 15-Minute Probability estimates p_up and p_down for quarter-hour windows using a broader caller-supplied trend sample. Send 8-240 ordered caller-supplied BTC price observations, the target venue's opening price, and its close timestamp; optionally include UP/DOWN share prices and entry fees for a descriptive model-edge comparison. Returns a conservative probability pair, lean, input-quality score, model contract, and warnings for $0.003 USDC via x402 on Base or Solana. First-…

## Output

Returns a JSON object containing the probability pair (p_up, p_down), the directional lean ('up' or 'down'), a data quality score with label (e.g. 'adequate_input_coverage'), the number of observations used, a model contract object indicating version and calibration caveats, and a list of warnings (e.g. 'probability_is_uncalibrated', 'not_trading_advice'). Optionally includes a model-edge comparison if share prices and fees were supplied.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "fee_bps": {
   "type": "integer",
   "maximum": 1000,
   "minimum": 0
  },
  "observations": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "timestamp",
     "price"
    ],
    "properties": {
     "price": {
      "type": "number",
      "maximum": 1000000000000000,
      "minimum": 1e-12
     },
     "timestamp": {
      "type": "integer",
      "minimum": 1
     }
    },
    "additionalProperties": false
   },
   "maxItems": 240,
   "minItems": 8
  },
  "market_up_price": {
   "type": "number",
   "maximum": 1,
   "minimum": 0
  },
  "market_down_price": {
   "type": "number",
   "maximum": 1,
   "minimum": 0
  },
  "window_open_price": {
   "type": "number",
   "maximum": 1000000000000000,
   "minimum": 1e-12
  },
  "window_close_timestamp": {
   "type": "integer",
   "minimum": 1
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "asset": "BTC",
  "model": {
   "version": "delx-local-updown-v1",
   "no_live_market_data": true,
   "probability_is_uncalibrated": true,
   "deterministic_for_same_input": true
  },
  "schema": "delx/prediction-updown-estimate/v1",
  "status": "estimate",
  "estimate": {
   "lean": "up",
   "p_up": 0.800406,
   "p_down": 0.199594
  },
  "warnings": [
   "caller_supplied_prices_not_verified",
   "probability_is_uncalibrated",
   "not_trading_advice"
  ],
  "data_quality": {
   "label": "adequate_input_coverage",
   "score": 0.754056,
   "observations_used": 8
  },
  "horizon_minutes": 15,
  "input_provenance": "caller_supplied"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-btc-up-down-15-minute-probability-00883f95/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)