Competitor Change Monitor API

Detect meaningful text changes on public competitor pages between Actor runs.

What this Actor does

Competitor Change Monitor API fetches public pages, extracts main text, stores snapshots in Apify Key-Value Store, compares later runs against the previous snapshot, and saves structured change records to the Apify Dataset.

The first run creates a baseline. Later runs can report added text, removed text, change score, keywords, and likely change types.

Use cases

• Monitor competitor pricing pages.
• Watch changelogs and docs for product updates.
• Track public legal, policy, blog, and marketing page edits.
• Feed structured change records into Slack, dashboards, or reporting workflows.

Who this is for

Competitor intelligence teams, founders, marketers, product teams, agencies, and analysts who monitor public website changes.

Input

• urls - Public pages to monitor. Required, 1-100 items.
• compareMode - Text comparison mode. Current supported value: text.
• includeScreenshot - Reserved for a browser-based upgrade. Current version returns screenshotUrl: null. Default: false.
• maxPages - Maximum pages to check in one run. Default: 50, maximum: 100.
• changeSensitivity - How small a text difference must be before a change is marked. Values: low, medium, high. Default: medium.

Example input

{
  "urls": ["https://www.apify.com/pricing", "https://www.apify.com/changelog"],
  "compareMode": "text",
  "includeScreenshot": false,
  "maxPages": 10,
  "changeSensitivity": "medium"
}

Output

The Actor saves one Dataset item per checked URL.

• sourceUrl - Final fetched page URL.
• pageTitle - HTML page title.
• currentHash - SHA-1 hash of current main text.
• previousHash - SHA-1 hash from the previous run, or null on the first baseline run.
• changeDetected - Whether a change passed the selected sensitivity threshold.
• changeScore - Approximate changed-line ratio from 0 to 1.
• changedSections - Added text snippets used as a quick summary.
• addedText - New text snippets.
• removedText - Removed text snippets.
• importantKeywords - Detected keywords such as pricing, security, API, deprecated, or launch.
• detectedChangeTypes - Heuristic categories such as pricing_change, feature_change, docs_change, or legal_change.
• screenshotUrl - Always null in this version.
• scrapedAt - ISO timestamp for the run.
• previousScrapedAt - Timestamp from the previous snapshot when available.
• errorMessage - Failure reason when a page request fails.

Example output

{
  "sourceUrl": "https://www.apify.com/pricing",
  "pageTitle": "Pricing",
  "currentHash": "abc123",
  "previousHash": "def456",
  "changeDetected": true,
  "changeScore": 0.2,
  "changedSections": ["New plan launched"],
  "addedText": ["New plan launched"],
  "removedText": ["Old plan removed"],
  "importantKeywords": ["pricing"],
  "detectedChangeTypes": ["pricing_change"],
  "screenshotUrl": null,
  "scrapedAt": "2026-07-04T00:00:00.000Z",
  "previousScrapedAt": "2026-07-03T00:00:00.000Z",
  "errorMessage": null
}

How it works

• Reads the Actor input.
• Deduplicates public URLs.
• Fetches each page and extracts main text.
• Stores the latest snapshot in Apify Key-Value Store.
• Compares against the previous snapshot for that URL.
• Saves change records to the Apify Dataset.

Limitations

• First runs create a baseline and do not report a change.
• Public pages only.
• No login, private data, cookies, CAPTCHA bypass, or restricted content.
• Text diff is heuristic and may include navigation or layout text if the page structure changes.
• Screenshot diff is not implemented in this version.
• Dynamic pages may need a browser-based upgrade for better extraction.

Error handling

Invalid or empty urls input fails run validation. Failed requests return a Dataset item with extractionStatus: "failed", errorMessage, changeDetected: false, and null hashes. Snapshot read/write is handled through Apify Key-Value Store during normal Actor runs.

Troubleshooting

• If no change is reported on the first run, that is expected: the first run creates the baseline.
• If changes look noisy, lower sensitivity by setting changeSensitivity to low or monitor more stable page URLs.
• If small edits are missed, use changeSensitivity: "high".
• If a page fails, confirm it is publicly accessible and does not require login, cookies, or browser-only rendering.

API usage

curl -X POST "https://api.apify.com/v2/acts/USERNAME~competitor-change-monitor-api/runs?token=YOUR_APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "urls": ["https://www.apify.com/pricing"],
    "compareMode": "text",
    "includeScreenshot": false,
    "maxPages": 10,
    "changeSensitivity": "medium"
  }'

Integration ideas

• Schedule daily or weekly monitoring runs.
• Send records with changeDetected: true to Slack or email.
• Store changes in a competitor intelligence dashboard.
• Pair with Sitemap Intelligence API to discover URLs before monitoring them.

SEO keywords

competitor monitor, website change API, pricing change monitor, changelog monitor, docs monitor, public page monitoring, Apify monitor, text diff API, competitor intelligence, change detection

Ethical use

This Actor is designed for public data and user-provided URLs only. Do not use it to access private, login-protected, or restricted content.