# PageDiff API - Wayback Machine Snapshot Differ

> PageDiff API - Wayback Machine Snapshot Differ is a paid API for AI agents from pagediff-api.hahavoid0.workers.dev, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Compares two Wayback Machine snapshots of a URL across two dates and returns structured added, removed, and modified text blocks

## Facts

- Endpoint: GET https://pagediff-api.hahavoid0.workers.dev/diff
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pagediff-api-wayback-machine-snapshot-differ-f316d434
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LhbQZEU-qM5-d-LKU_5PX

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 pagediff-api-wayback-machine-snapshot-differ-f316d434
```

Example prompt: Can you diff the content of https://www.nytimes.com/ between January 1 2023 and January 1 2024 — I want to see what text was added, removed, or changed on the page across those two Wayback Machine snapshots?

## When to prefer this

Use this endpoint when you need to programmatically detect and extract what text content changed on a specific public web page between two historical dates, leveraging Wayback Machine archives. Ideal for monitoring agents, research tasks, or auditing content changes over time without needing to store page snapshots yourself. Prefer this over generic scraping when you need historical comparison rather than current content.

## Known failure modes

- No Wayback Machine snapshot found near the requested date — returns error or empty snapshot metadata
- URL has never been archived by the Wayback Machine — results in missing snapshot data
- Date format not YYYY-MM-DD — request may fail or return unexpected results
- Target page is behind authentication or returns non-200 status in archive — snapshot may be incomplete
- Payment of $0.05 USDC not completed — returns HTTP 402 before processing

## How this service works

Pay-per-call historical page-change evidence for AI agents. Check Wayback snapshot availability, compare archived pages, and generate structured reports with important changes, impact, risks, and source timestamps.

## Output

A JSON object containing arrays of added, removed, and modified text blocks found between the two Wayback Machine snapshots, plus a summary with counts and a qualitative change_level (e.g. 'low', 'medium', 'high'), and metadata for each snapshot including archive URL, digest, timestamp, MIME type, and HTTP status code.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "to": {
   "type": "string",
   "examples": [
    "2024-01-01"
   ],
   "description": "Requested later snapshot date in YYYY-MM-DD format."
  },
  "url": {
   "type": "string",
   "examples": [
    "https://example.com/"
   ]
  },
  "from": {
   "type": "string",
   "examples": [
    "2023-01-01"
   ],
   "description": "Requested earlier snapshot date in YYYY-MM-DD format."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "url": "https://example.com/",
  "added": [
   "Updated example page content."
  ],
  "removed": [
   "Original example page content."
  ],
  "summary": {
   "added_count": 1,
   "change_level": "low",
   "removed_count": 1,
   "modified_count": 0
  },
  "modified": [],
  "to_snapshot": {
   "digest": "EXAMPLE2",
   "mimetype": "text/html",
   "timestamp": "20240101000000",
   "statuscode": "200",
   "archive_url": "https://web.archive.org/web/20240101000000id_/https://example.com/",
   "original_url": "https://example.com/",
   "requested_date": "2024-01-01"
  },
  "from_snapshot": {
   "digest": "EXAMPLE",
   "mimetype": "text/html",
   "timestamp": "20230101000000",
   "statuscode": "200",
   "archive_url": "https://web.archive.org/web/20230101000000id_/https://example.com/",
   "original_url": "https://example.com/",
   "requested_date": "2023-01-01"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pagediff-api-wayback-machine-snapshot-differ-f316d434/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pagediff-api.hahavoid0.workers.dev](https://www.zero.xyz/host/pagediff-api.hahavoid0.workers.dev/llms.txt)