# Extract Meta Tags as JSON – Change Watch

> Extract Meta Tags as JSON – Change Watch is a paid API for AI agents from page.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-20).

Monitors a web page's meta tags for changes, returning current meta tag JSON along with a changed flag, before/after diffs, and last-seen timestamp.

## Facts

- Endpoint: GET https://page.intel.rallylive.ca/watch/page/meta-tags/json?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/extract-meta-tags-as-json-change-watch-72c60f19
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ErWiYpL07UGXsMNZqQngI

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 extract-meta-tags-as-json-change-watch-72c60f19
```

Example prompt: Keep an eye on the meta tags for https://example.com — let me know if anything changes compared to last time you checked, and show me exactly what's different.

## When to prefer this

Choose this endpoint when you need change-detection semantics on top of meta tag extraction — i.e., you want to know not just what the current meta tags are, but whether they have changed since your last check, and what specifically changed. Prefer it for scheduled monitoring, SEO auditing pipelines, or alerting workflows where diff output (before/after fields) is more valuable than raw extraction alone.

## Known failure modes

- Target URL is unreachable or returns a non-200 status, resulting in an error or no meta tag data
- No previous snapshot exists (first call), so 'changed' may default to false or be indeterminate
- Meta tags have no standard structure on the page, returning an empty or minimal result
- Snapshot older than 90 days has been purged, losing the comparison baseline
- Payment of $0.02 USDC not fulfilled, blocking the request via x402 protocol

## How this service works

Change watch for extract meta tags as json: runs the check, compares it with the result from your previous call for the same url (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 meta tags as a JSON object, a boolean 'changed' flag indicating whether anything differs from the previous check (stored up to 90 days), the specific fields that changed with their before and after values, and a timestamp of when the page was last observed.

## 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/extract-meta-tags-as-json-change-watch-72c60f19/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from page.intel.rallylive.ca](https://www.zero.xyz/host/page.intel.rallylive.ca/llms.txt)