# Page Change Monitor (`toumi.oussema.re/page-change-monitor`) Actor

Surveille une ou plusieurs pages web (contenu entier ou sélecteur CSS précis) et notifie un webhook dès qu'un changement ou un mot-clé est détecté. Conçu pour être planifié en boucle (Apify Scheduler) — revenu récurrent proportionnel à la fréquence de surveillance.

- **URL**: https://apify.com/toumi.oussema.re/page-change-monitor.md
- **Developed by:** [Oussema Toumi](https://apify.com/toumi.oussema.re) (community)
- **Categories:** Automation, SEO tools, Social media
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $3.00 / 1,000 vérification effectuées

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/platform/actors/running/actors-in-store#pay-per-event

## What's an Apify Actor?

Actors are web data automations that power AI and operations. They run on the Apify platform to scrape websites, process data, connect APIs, and automate workflows.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.
Actors are written with capital "A".

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.
The best way to integrate Actors is as follows.

- **AI agents and MCP clients** — the [Apify MCP server](https://docs.apify.com/integrations/mcp.md) at `https://mcp.apify.com` (remote, streamable HTTP, OAuth on first use).
- **Agentic workflows and local Actor development** — [Agent Skills](https://apify.com/.well-known/agent-skills/index.json) with the [Apify CLI](https://docs.apify.com/cli/docs.md): `npm install -g apify-cli`, then `apify login`.
- **JavaScript/TypeScript projects** — the official [JS/TS client](https://docs.apify.com/api/client/js/docs.md): `npm install apify-client`.
- **Python projects** — the official [Python client](https://docs.apify.com/api/client/python/docs.md): `pip install apify-client`.
- **Any other language** — the [REST API](https://docs.apify.com/api/v2.md).

For usage examples, see the [API](#api) section below.

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).

# README

## Page Change Monitor

Monitors one or more web pages (full content or a precise CSS selector) and
notifies a webhook as soon as a change is detected, or when a watched keyword
appears/disappears. Designed to run on a **schedule** via the Apify Scheduler
(e.g. every hour, every day) - that is what turns it into a true recurring
revenue source instead of a one-shot.

### Input

| Field | Type | Description |
|---|---|---|
| `monitors` | array | List of `{ url, selector? , keyword? }` |
| `webhookUrl` | string | URL called with a POST on each notification. Optional: if empty, notifications are only logged. |
| `notifyOnlyOnChange` | bool | If false, also notifies when nothing changed (heartbeat mode) |

Example input:

```json
{
  "monitors": [
    { "url": "https://example.com", "selector": "", "keyword": "" },
    { "url": "https://news.ycombinator.com", "selector": "a.titlelink", "keyword": "AI" }
  ],
  "webhookUrl": "https://your-app.example.com/hooks/page-changed",
  "notifyOnlyOnChange": true
}
```

### How it works

1. On each run, the actor fetches the content of every page (or of the given
   CSS selector).
2. It compares a hash of the current content with the hash of the last run,
   **stored in the actor's default Key-Value Store** (persists across
   scheduled runs).
3. If the content changed (or the watched keyword appeared/disappeared), it
   notifies `webhookUrl` with the details, then updates the stored state.

The first run of a new monitor has no previous state, so it is counted as
"changed" and triggers a notification - documented behavior, not a bug.

### Setting up scheduling

In the Apify Console: **Actor → Schedules → Create new schedule**, set the
frequency (e.g. `0 * * * *` for hourly) and the same `Input` (monitors +
webhookUrl). This recurring schedule is what generates the recurring revenue.

### Pricing (pay-per-event)

- `check-performed` — $0.003 — per URL checked, on every scheduled run
- `change-detected` — $0.01 — additionally, when a change is detected AND
  the webhook was notified successfully

Example: 5 URLs monitored every hour (720 checks/month), with ~30 detected
changes in the month ≈
(720 × $0.003) + (30 × $0.01) = $2.16 + $0.30 = **$2.46/month** per user
monitoring 5 pages - revenue grows with the number of users and monitored
pages, with no extra infrastructure cost on your side (everything runs on
Apify).

### Technical notes

- No GPU required, no external API key required for the base version (no LLM
  involved).
- A failed fetch for a URL is never charged.
- State is stored under a key derived from `url + selector` - two monitors on
  the same URL with different selectors are tracked independently.

# Actor input Schema

## `monitors` (type: `array`):

List of objects { "url": string, "selector": string (optional), "keyword": string (optional) }. Without a selector, the whole cleaned page is monitored.

## `webhookUrl` (type: `string`):

Called with a POST (JSON) on every detected change. Optional: if empty, notifications are only logged (no webhook call, no change-detected charge).

## `notifyOnlyOnChange` (type: `boolean`):

If disabled, the webhook is also called when nothing changed (useful for a heartbeat)

## Actor input object example

```json
{
  "monitors": [
    {
      "url": "https://example.com",
      "selector": "",
      "keyword": ""
    }
  ],
  "webhookUrl": "",
  "notifyOnlyOnChange": true
}
```

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {};

// Run the Actor and wait for it to finish
const run = await client.actor("toumi.oussema.re/page-change-monitor").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {}

# Run the Actor and wait for it to finish
run = client.actor("toumi.oussema.re/page-change-monitor").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{}' |
apify call toumi.oussema.re/page-change-monitor --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,toumi.oussema.re/page-change-monitor"
        }
    }
}

```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/klv2y5zgSIa6aiyFi/builds/P0uPVxPMKcusOffxR/openapi.json