# ylk.one Day-over-Day x402 Rail Shift

> ylk.one Day-over-Day x402 Rail Shift is a paid API for AI agents from ylk.one, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-16).

Returns day-over-day delta metrics for the x402 payment rail including total volume and transaction count changes, and lane-level UP/DOWN movements across commerce, inference, and dev segments.

## Facts

- Endpoint: GET https://ylk.one/v1/shift?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ylk-one-day-over-day-x402-rail-shift-e6756fcc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_r_m881OIXQ_3k7ljhHSn2

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 ylk-one-day-over-day-x402-rail-shift-e6756fcc
```

Example prompt: Can you pull the day-over-day x402 rail shift report — I want to see how total dollar volume and transaction count changed since yesterday, and which lanes like commerce or inference are trending up or down?

## When to prefer this

Use this endpoint when you need a day-over-day summary of x402 rail activity — specifically the net change in volume and transactions since yesterday, and which lanes are expanding or contracting. Prefer this over the sibling live-snapshot endpoint (ylk-spikes or the live rail endpoint) when you want daily trend context rather than intra-day or real-time pace data.

## Known failure modes

- No data available for prior day if the rail is too new or there was a data gap — may return null deltas or 404
- Rate limit or payment failure (402) if USDC microtransaction is not processed
- Stale data if on-chain indexing is lagging — deltas may not reflect most recent blocks
- Empty lane breakdown if no activity occurred in a specific lane during the window

## How this service works

Day-over-day x402 rail movement from on-chain settlement: total $ and tx deltas, lanes UP and DOWN (commerce, inference, dev…). Pairs with ylk-spikes for intra-day vs day-over-day reads.

## Output

A JSON object containing day-over-day deltas: total dollar change, transaction count change, and per-lane (commerce, inference, dev, etc.) UP/DOWN movement indicators reflecting net shifts in on-chain x402 settlement activity compared to the prior day.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ylk-one-day-over-day-x402-rail-shift-e6756fcc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ylk.one](https://www.zero.xyz/host/ylk.one/llms.txt)