# Duolingo.com Downtime Change Watch

> Duolingo.com Downtime Change Watch is a paid API for AI agents from monitor.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-02).

Runs a live check of duolingo.com, compares the result against the previous call (retained 90 days), and returns whether its status changed along with before/after field diffs.

## Facts

- Endpoint: GET https://monitor.intel.rallylive.ca/watch/monitor/is-down/duolingo-com?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/duolingo-com-downtime-change-watch-7a2473ab
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_c44Pze2xDKRMwfQONY2MV

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 duolingo-com-downtime-change-watch-7a2473ab
```

Example prompt: Keep an eye on duolingo.com for me and let me know the moment its availability status changes from what it was last time — I want to know if it goes down or comes back up.

## When to prefer this

Use this endpoint when you need change-aware monitoring of duolingo.com specifically — not just a raw status check, but delta detection that tells you whether anything is different from the last observation. Ideal for agents that need to fire alerts only on state transitions rather than polling raw status on every check. Best when integrated into a scheduled workflow where repeated calls compare against stored prior state.

## Known failure modes

- Network timeout reaching duolingo.com from edge — may return error or stale data
- No previous check stored yet for this query — 'changed' may be null or undefined on first call
- Duolingo.com returns unexpected HTTP status that doesn't map cleanly to up/down
- Payment failure ($0.02 USDC) causes the check not to execute
- Rate limiting or throttling on the monitoring endpoint itself

## How this service works

Change watch for is duolingo com down: runs the check, compares it with the result from your previous call for the same query (kept 90 days) and returns the current answer, changed true/false, the fields that changed with before/after values, and when it was last seen. Schedule it to be alerted when this changes. $0.02 per check.

## Output

Returns the current up/down status of duolingo.com, a boolean 'changed' field indicating whether the result differs from the previous call, a list of fields that changed with their before and after values, and the timestamp of when the status was last observed. Previous results are retained for 90 days per query.

## 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/duolingo-com-downtime-change-watch-7a2473ab/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from monitor.intel.rallylive.ca](https://www.zero.xyz/host/monitor.intel.rallylive.ca/llms.txt)