GET /v1/board/{category}/delta

$0.015realtimetier: datacache 60sEngine A — Probability API

Keyset delta of /v1/board/:category: pass since=<next_cursor from your last call> and get only the materially-moved markets in the segment added or changed after it, plus changed_count and a new next_cursor. Omit since once to bootstrap. Cursors are stable across restarts. Poll the free sibling /v1/board/:category/changes for counts and pay only when there is something to fetch.

An unknown, malformed, or future cursor returns 400 with a pointer at the parent snapshot. Responses are always well-formed, even when empty. At most 500 rows per call; follow next_cursor for more.

Parameters

Example

curl "https://x402-factory.com/v1/board/economics/delta"

Bootstrap call: empty delta plus a cursor at now.

Example response

{
  "data": {
    "rows": [],
    "changed_count": 0,
    "next_cursor": "djF8MjAyNi0wNy0xOFQxMjowMDowMC4wMDBafA",
    "as_of": "2026-07-18T12:00:00.000Z"
  },
  "meta": {
    "endpoint": "/v1/board/{category}/delta",
    "version": "1.0.0",
    "generated_at": "2026-09-13T09:52:16.095Z",
    "freshness": "realtime",
    "sources": [
      "kalshi",
      "polymarket"
    ],
    "request_id": "req_00000000",
    "docs": "https://x402-factory.com/docs/probability.board.delta",
    "data_mode": "live"
  }
}

Response schema (data payload)

{
  "type": "object",
  "properties": {
    "rows": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "slug": {
            "type": "string"
          },
          "question": {
            "type": "string"
          },
          "category": {
            "type": "string"
          },
          "p": {
            "type": "number",
            "minimum": 0,
            "maximum": 1
          },
          "prev_p": {
            "type": "number",
            "minimum": 0,
            "maximum": 1
          },
          "delta": {
            "type": "number"
          },
          "changed_at": {
            "type": "string"
          }
        },
        "required": [
          "slug",
          "question",
          "category",
          "p",
          "prev_p",
          "delta",
          "changed_at"
        ],
        "additionalProperties": false
      }
    },
    "changed_count": {
      "type": "integer",
      "minimum": 0,
      "maximum": 9007199254740991
    },
    "next_cursor": {
      "type": "string"
    },
    "as_of": {
      "type": "string"
    }
  },
  "required": [
    "rows",
    "changed_count",
    "next_cursor",
    "as_of"
  ],
  "additionalProperties": false
}

The platform wraps every payload in an envelope: { "data": …, "meta": { endpoint, version, generated_at, freshness, sources, request_id, docs, data_mode } }.

Payment (x402)

Unpaid requests receive 402 with payment requirements (accepts). Pay $0.015 in USDC on Base per call via an X-PAYMENT header — see docs.x402.org. With PAYMENT_MODE=disabled (local dev) the endpoint is open.

Errors