# x402-factory Calendar Events Delta

> x402-factory Calendar Events Delta is a paid API for AI agents from x402-factory.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns only calendar events (prediction market questions) added, resolved, or changed since a given cursor position, enabling efficient incremental polling.

## Facts

- Endpoint: GET https://x402-factory.com/v1/calendar/delta
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-factory-calendar-events-delta-3f85c795
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xA9iikyd8xJtEq9SJ6J_4

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 x402-factory-calendar-events-delta-3f85c795
```

Example prompt: Give me only the prediction market calendar events that have changed or been added since my last cursor — use the next_cursor from the previous call, or bootstrap a fresh one if I don't have one yet.

## When to prefer this

Choose this endpoint when you already have a next_cursor from a previous call and want only the incremental changes to prediction market calendar events rather than the full list. It is ideal for agents that need to stay continuously in sync with the market calendar without re-downloading unchanged data. Use the sibling /v1/calendar/changes endpoint (free) first to check if polling is worthwhile before spending $0.005 USDC per call.

## Known failure modes

- Invalid or expired cursor returns an error or resets to bootstrap state
- Missing required 'since' parameter format causes a 400 bad request
- Payment not settled (x402 protocol failure) results in a 402 Payment Required response
- Network timeout if the backend is slow to compute the delta
- Rate limiting if polled too frequently in a short window

## How this service works

Only the calendar events added or resolved changed since your cursor (delta of / — Keyset delta of /v1/calendar: pass since=<next_cursor from your last call> and get only the calendar events added or resolved 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/calendar/changes for counts…

## Output

Returns a JSON object with a 'rows' array of changed calendar events (each containing slug, question, category, resolution_date, change type, and changed_at timestamp), a changed_count integer, an as_of timestamp, and a next_cursor string to use in the next incremental poll.

## 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",
     "required": [],
     "properties": {
      "since": {
       "type": "string",
       "maxLength": 300,
       "minLength": 4,
       "description": "Opaque cursor from a previous next_cursor; omit once to bootstrap a cursor at now"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "data",
      "meta"
     ],
     "properties": {
      "data": {
       "type": "object",
       "required": [
        "rows",
        "changed_count",
        "next_cursor",
        "as_of"
       ],
       "properties": {
        "rows": {
         "type": "array",
         "items": {
          "type": "object",
          "required": [
           "slug",
           "question",
           "category",
           "resolution_date",
           "change",
           "changed_at"
          ],
          "properties": {
           "slug": {
            "type": "string"
           },
           "change": {
            "type": "string"
           },
           "category": {
            "type": "string"
           },
           "question": {
            "type": "string"
           },
           "changed_at": {
            "type": "string"
           },
           "resolution_date": {
            "type": "string"
           }
          },
          "additionalProperties": false
         }
        },
        "as_of": {
         "type": "string"
        },
        "next_cursor": {
         "type": "string"
        },
        "changed_count": {
         "type": "integer",
         "maximum": 9007199254740991,
         "minimum": 0
        }
       },
       "additionalProperties": false
      },
      "meta": {
       "type": "object"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-factory-calendar-events-delta-3f85c795/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-factory.com](https://www.zero.xyz/host/x402-factory.com/llms.txt)