# ylk.one x402 Rails Snapshot

> ylk.one x402 Rails Snapshot is a paid API for AI agents from ylk.one, paid per call via x402, $0.02/call, status down (last checked 2026-10-19).

Returns a live, sanitized JSON snapshot of x402 payment rail metrics including pace, median ticket size, top receivers by dollar volume, and recent settlements.

## Facts

- Endpoint: GET https://ylk.one/v1/x402/rails?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: down
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ylk-one-x402-rails-snapshot-f9a0efd7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YC0yZEvrIUePsY9jOGrH7

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-x402-rails-snapshot-f9a0efd7
```

Example prompt: Pull the latest x402 rail snapshot for me — I want to see the current pace, median ticket, and top receivers by dollar volume on Base so I can decide what to do next.

## When to prefer this

Use this endpoint when you need a real-time, sanitized, machine-readable view of x402 payment rail activity — specifically for agent decision-branching on which services are active, how busy the rail is, or what the typical transaction size looks like. Prefer this over day-over-day delta endpoints (the sibling endpoint) when you need an absolute snapshot rather than change metrics.

## Known failure modes

- Chain ID not recognized — returns error indicating unsupported chain
- Rail data temporarily unavailable — upstream on-chain indexer lag
- Payment of $0.02 USDC not received — x402 402 response requiring payment
- Malformed query parameter — returns validation error for invalid chain value

## How this service works

Live sanitized x402 rail snapshot JSON: pace/min, median ticket, top receivers by $, recent settlements. Machine-readable ylk.rails.public.v1 — agents branch on topServices.

## Output

A machine-readable JSON object (schema ylk.rails.public.v1) containing: current transaction pace in per-minute rate, median ticket size in USD/USDC, ranked list of top receivers by total dollar volume, and a list of recent settlement events. Structured so agents can branch logic on topServices and rail health indicators.

## 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": {
      "chain": {
       "type": "string",
       "description": "chain id (default base)"
      }
     },
     "additionalProperties": false
    }
   },
   "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-x402-rails-snapshot-f9a0efd7/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)