# Product Feed Price & Stock Delta Monitor (`stellar_ballet_0bu/product-feed-delta-monitor`) Actor
Monitor public product feeds in JSON, XML, RSS, Google Merchant, or CSV formats for price drops, stock changes, removed products, and clean stateful deltas.
- **URL**: https://apify.com/stellar\_ballet\_0bu/product-feed-delta-monitor.md
- **Developed by:** [Nikita S](https://apify.com/stellar_ballet_0bu) (community)
- **Categories:** E-commerce, Automation, AI
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet
## Pricing
Pay per usage
This Actor is paid per platform usage. The Actor is free to use, and you only pay for the Apify platform usage, which gets cheaper the higher subscription plan you have.
Learn more: https://docs.apify.com/platform/actors/running/actors-in-store#pay-per-usage
## What's an Apify Actor?
Actors are a software tools running on the Apify platform, for all kinds of web data extraction and automation use cases.
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.
In JavaScript/TypeScript projects, use official [JavaScript/TypeScript client](https://docs.apify.com/api/client/js.md):
```bash
npm install apify-client
```
In Python projects, use official [Python client library](https://docs.apify.com/api/client/python.md):
```bash
pip install apify-client
```
In shell scripts, use [Apify CLI](https://docs.apify.com/cli/docs.md):
````bash
# MacOS / Linux
curl -fsSL https://apify.com/install-cli.sh | bash
# Windows
irm https://apify.com/install-cli.ps1 | iex
```bash
In AI frameworks, you might use the [Apify MCP server](https://docs.apify.com/platform/integrations/mcp.md).
If your project is in a different language, use 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
## Product Feed Price & Stock Delta Monitor
Monitor public product feeds — JSON APIs, XML/RSS/Atom feeds, Google Merchant feeds, and CSV exports — and emit only products that changed since the previous run.
Use it for:
- supplier feed monitoring;
- affiliate/catalog price changes;
- competitor product-feed deltas;
- back-in-stock and sold-out alerts;
- Google Sheets, n8n, Make, Slack, or Discord workflows.
This Actor is intentionally feed-first: it avoids browser scraping and anti-bot fights. If a store already exposes a feed/API/export, this is the cheap reliable monitor.
### Visual demo: Product Feed Delta Monitor
These images are hosted in a persistent Apify key-value store so the Store README has stable, clickable visual previews.
### Input
```json
{
"feedUrls": ["https://woocommerce.com/wp-json/wc/store/v1/products?per_page=5"],
"onlyChanged": true,
"persistState": true,
"minPriceChangePct": 0,
"priceDropAlertPct": 20
}
````
Supported formats:
- JSON arrays or objects with `products`, `items`, `data`, or `results`;
- XML/RSS/Atom/Google Merchant `- ` or `` feeds;
- CSV feeds with headers like `id,title,link,price,availability`.
### Output
Rows include:
- `feedUrl`
- `productId`
- `sku`
- `name`
- `brand`
- `productUrl`
- `price`
- `currency`
- `availability`
- `available`
- `status`
- `event`
- `events`
- `event_severity`
- `changes`
Example:
```json
{
"feedUrl": "https://example.com/products.xml",
"productId": "SKU-1",
"name": "Example Jacket",
"productUrl": "https://example.com/products/jacket",
"price": 70,
"currency": "EUR",
"availability": "out_of_stock",
"available": false,
"status": "changed",
"event": "price_change",
"events": ["price_change", "sold_out"],
"event_severity": "high",
"changes": [
{ "field": "price", "before": 100, "after": 70 }
]
}
```
### Events
- `new_product`
- `price_change`
- `availability_change`
- `restock`
- `sold_out`
- `removed_product`
- `unchanged` if requested
- `error`
### Monetization hooks
The Actor emits Pay-Per-Event hooks for meaningful deltas:
- `delta_result` for new/changed/removed product rows;
- `price_drop_alert` for price drops at or above the configured threshold;
- `apify-actor-start` once per run/user when enabled by platform pricing.
### Notes
- This Actor does not bypass CAPTCHA, login walls, Cloudflare, or anti-bot systems.
- For Shopify/WooCommerce/product-page JSON-LD monitoring, use the sibling specialized Actors when they fit better.
- For scheduled monitoring, keep `persistState=true` so each run compares against the previous snapshot.
### Run it from Claude / Cursor / VS Code via MCP
The Actor is available through the Apify MCP server, so you can ask your AI assistant to "poll this feed daily and email me the changes" instead of writing a cron job.
Add this to your MCP client config (for example `claude_desktop_config.json`):
```json
{
"mcpServers": {
"apify": {
"command": "npx",
"args": ["-y", "@apify/mcp-server"],
"env": {
"APIFY_TOKEN": "your-apify-api-token"
}
}
}
}
```
Once connected, the assistant can discover this Actor and trigger runs with a plain prompt like *"Run Product Feed Delta Monitor on https://example.com/feed.csv every 6 hours and list the new SKUs."* The remote MCP server at `https://mcp.apify.com` works the same way without a local install.
### Quick start
1. Open this Actor in Apify Console.
2. Paste one or more product feed/API URLs into the input.
3. Keep `persistState` enabled for scheduled monitoring.
4. Run once to create the baseline snapshot.
5. Run again on a schedule to receive only delta rows.
6. Export the dataset to CSV/JSON, or send it to Google Sheets, n8n, Make, Slack, Discord, or a webhook.
### Sample output
Use this sample dataset to see the output shape before running it yourself:
- Sample dataset: https://console.apify.com/storage/datasets/OUqxDLrOKXPcVjR2o
The important fields for automation are `event`, `events`, `event_severity`, `status`, and `changes`. Filter for `event_severity = high` when you only want alerts that deserve immediate attention.
### Pricing and cost expectations
This Actor is designed for scheduled monitoring and delta-only outputs. It avoids charging or processing unchanged rows where possible. Pay-Per-Event pricing is scheduled/used for meaningful emitted deltas such as new items, removed items, price changes, stock changes, URL changes, or pricing-plan changes depending on the Actor.
Start with a small input list first. Once the baseline looks correct, schedule recurring runs and set a reasonable max charge limit in Apify.
### FAQ
#### Is this a one-time scraper or a monitor?
It is a monitor. The first run creates a baseline. Later runs compare the current data against the stored baseline and emit only the changes.
#### Can I send alerts to Slack, Discord, Google Sheets, n8n, or Make?
Yes. Use Apify integrations, webhooks, dataset export, or API polling. The `event`, `events`, `event_severity`, and `changes` fields are meant for automation routing.
#### Does it bypass CAPTCHA, login walls, or anti-bot systems?
No. This portfolio is intentionally focused on public, low-risk sources such as public APIs, feeds, sitemaps, product pages, or storefront endpoints.
#### Which rows should trigger alerts?
Use `event_severity`. High-severity rows are the best candidates for Slack/Discord/email alerts. Low-severity rows are usually better for reports or spreadsheets.
### Support and custom monitoring
If a public source does not fit this Actor, check the related monitors below. Open an issue on the Actor page with a sample URL and the output you need.
### Which monitor should I use?
This Actor is part of a focused monitoring portfolio. Pick the narrowest Actor that matches your source:
| Source you have | Use this Actor | Best for |
|---|---|---|
| Shopify store | [Shopify Delta Monitor](https://apify.com/stellar_ballet_0bu/shopify-delta-monitor) | Shopify competitor price/stock/sale monitoring |
| WooCommerce store | [WooCommerce Delta Monitor](https://apify.com/stellar_ballet_0bu/woocommerce-delta-monitor) | WooCommerce Store API product deltas |
| Product page URLs with Schema.org JSON-LD | [Schema.org Product Delta Monitor](https://apify.com/stellar_ballet_0bu/schema-product-delta-monitor) | Magento, BigCommerce, custom stores, marketplaces |
| Product feeds / APIs / CSV / XML | [Product Feed Delta Monitor](https://apify.com/stellar_ballet_0bu/product-feed-delta-monitor) | Supplier feeds, affiliate feeds, Google Merchant exports |
| sitemap.xml | [Sitemap Delta Monitor](https://apify.com/stellar_ballet_0bu/sitemap-delta-monitor) | SEO, content ops, RAG indexing queues |
| SaaS pricing pages | SaaS Pricing Page Monitor | Plan/price/feature changes on public pricing pages |
All monitors are built for scheduled runs, stateful comparisons, delta-only outputs, and workflow automation via Google Sheets, n8n, Make, Slack, Discord, or webhooks.
# Actor input Schema
## `feedUrls` (type: `array`):
Public product feeds or product APIs in JSON, XML/RSS/Google Merchant, or CSV format.
## `previousItems` (type: `array`):
Optional previous product rows from an earlier run. Used to compute deltas.
## `onlyChanged` (type: `boolean`):
Skip unchanged products. New, changed, removed, and error rows are still emitted.
## `persistState` (type: `boolean`):
Store the latest feed snapshot in a named key-value store so scheduled runs emit deltas next time.
## `stateStoreName` (type: `string`):
Named key-value store used for snapshots when persistState is enabled.
## `stateKey` (type: `string`):
Optional snapshot key. Leave empty to use one key derived from all input feed URLs.
## `minPriceChangePct` (type: `number`):
Minimum absolute percentage price change needed to emit a price\_change event. Set 0 to report every price change.
## `priceDropAlertPct` (type: `number`):
Price decreases at or above this threshold also emit price\_drop\_alert charging hook.
## Actor input object example
```json
{
"feedUrls": [
"https://woocommerce.com/wp-json/wc/store/v1/products?per_page=5"
],
"previousItems": [],
"onlyChanged": true,
"persistState": true,
"stateStoreName": "product-feed-delta-monitor-state",
"stateKey": "",
"minPriceChangePct": 0,
"priceDropAlertPct": 20
}
```
# Actor output Schema
## `deltaRows` (type: `string`):
Default dataset items with feed URL, product ID, SKU, name, URL, price, currency, availability, named events, event\_severity, and changes array.
## `summary` (type: `string`):
Run summary with feeds seen, products seen, emitted count, event counters, state key, and errors.
# 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 '' with your token
const client = new ApifyClient({
token: '',
});
// Prepare Actor input
const input = {
"feedUrls": [
"https://woocommerce.com/wp-json/wc/store/v1/products?per_page=5"
]
};
// Run the Actor and wait for it to finish
const run = await client.actor("stellar_ballet_0bu/product-feed-delta-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 '' with your token.
client = ApifyClient("")
# Prepare the Actor input
run_input = { "feedUrls": ["https://woocommerce.com/wp-json/wc/store/v1/products?per_page=5"] }
# Run the Actor and wait for it to finish
run = client.actor("stellar_ballet_0bu/product-feed-delta-monitor").call(run_input=run_input)
# Fetch and print Actor results from the run's dataset (if there are any)
print("💾 Check your data here: https://console.apify.com/storage/datasets/" + run["defaultDatasetId"])
for item in client.dataset(run["defaultDatasetId"]).iterate_items():
print(item)
# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start
```
## CLI example
```bash
echo '{
"feedUrls": [
"https://woocommerce.com/wp-json/wc/store/v1/products?per_page=5"
]
}' |
apify call stellar_ballet_0bu/product-feed-delta-monitor --silent --output-dataset
```
## MCP server setup
```json
{
"mcpServers": {
"apify": {
"command": "npx",
"args": [
"mcp-remote",
"https://mcp.apify.com/?tools=stellar_ballet_0bu/product-feed-delta-monitor",
"--header",
"Authorization: Bearer "
]
}
}
}
```
## OpenAPI specification
```json
{
"openapi": "3.0.1",
"info": {
"title": "Product Feed Price & Stock Delta Monitor",
"description": "Monitor public product feeds in JSON, XML, RSS, Google Merchant, or CSV formats for price drops, stock changes, removed products, and clean stateful deltas.",
"version": "0.1",
"x-build-id": "HWFuqJ7X9ggZAfNnT"
},
"servers": [
{
"url": "https://api.apify.com/v2"
}
],
"paths": {
"/acts/stellar_ballet_0bu~product-feed-delta-monitor/run-sync-get-dataset-items": {
"post": {
"operationId": "run-sync-get-dataset-items-stellar_ballet_0bu-product-feed-delta-monitor",
"x-openai-isConsequential": false,
"summary": "Executes an Actor, waits for its completion, and returns Actor's dataset items in response.",
"tags": [
"Run Actor"
],
"requestBody": {
"required": true,
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/inputSchema"
}
}
}
},
"parameters": [
{
"name": "token",
"in": "query",
"required": true,
"schema": {
"type": "string"
},
"description": "Enter your Apify token here"
}
],
"responses": {
"200": {
"description": "OK"
}
}
}
},
"/acts/stellar_ballet_0bu~product-feed-delta-monitor/runs": {
"post": {
"operationId": "runs-sync-stellar_ballet_0bu-product-feed-delta-monitor",
"x-openai-isConsequential": false,
"summary": "Executes an Actor and returns information about the initiated run in response.",
"tags": [
"Run Actor"
],
"requestBody": {
"required": true,
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/inputSchema"
}
}
}
},
"parameters": [
{
"name": "token",
"in": "query",
"required": true,
"schema": {
"type": "string"
},
"description": "Enter your Apify token here"
}
],
"responses": {
"200": {
"description": "OK",
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/runsResponseSchema"
}
}
}
}
}
}
},
"/acts/stellar_ballet_0bu~product-feed-delta-monitor/run-sync": {
"post": {
"operationId": "run-sync-stellar_ballet_0bu-product-feed-delta-monitor",
"x-openai-isConsequential": false,
"summary": "Executes an Actor, waits for completion, and returns the OUTPUT from Key-value store in response.",
"tags": [
"Run Actor"
],
"requestBody": {
"required": true,
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/inputSchema"
}
}
}
},
"parameters": [
{
"name": "token",
"in": "query",
"required": true,
"schema": {
"type": "string"
},
"description": "Enter your Apify token here"
}
],
"responses": {
"200": {
"description": "OK"
}
}
}
}
},
"components": {
"schemas": {
"inputSchema": {
"type": "object",
"required": [
"feedUrls"
],
"properties": {
"feedUrls": {
"title": "Product feed URLs",
"type": "array",
"description": "Public product feeds or product APIs in JSON, XML/RSS/Google Merchant, or CSV format.",
"items": {
"type": "string"
}
},
"previousItems": {
"title": "Previous items",
"type": "array",
"description": "Optional previous product rows from an earlier run. Used to compute deltas.",
"default": []
},
"onlyChanged": {
"title": "Only output changed items",
"type": "boolean",
"description": "Skip unchanged products. New, changed, removed, and error rows are still emitted.",
"default": true
},
"persistState": {
"title": "Persist state between runs",
"type": "boolean",
"description": "Store the latest feed snapshot in a named key-value store so scheduled runs emit deltas next time.",
"default": true
},
"stateStoreName": {
"title": "State store name",
"type": "string",
"description": "Named key-value store used for snapshots when persistState is enabled.",
"default": "product-feed-delta-monitor-state"
},
"stateKey": {
"title": "State key override",
"type": "string",
"description": "Optional snapshot key. Leave empty to use one key derived from all input feed URLs.",
"default": ""
},
"minPriceChangePct": {
"title": "Minimum price change %",
"minimum": 0,
"type": "number",
"description": "Minimum absolute percentage price change needed to emit a price_change event. Set 0 to report every price change.",
"default": 0
},
"priceDropAlertPct": {
"title": "Price-drop alert threshold %",
"minimum": 1,
"type": "number",
"description": "Price decreases at or above this threshold also emit price_drop_alert charging hook.",
"default": 20
}
}
},
"runsResponseSchema": {
"type": "object",
"properties": {
"data": {
"type": "object",
"properties": {
"id": {
"type": "string"
},
"actId": {
"type": "string"
},
"userId": {
"type": "string"
},
"startedAt": {
"type": "string",
"format": "date-time",
"example": "2025-01-08T00:00:00.000Z"
},
"finishedAt": {
"type": "string",
"format": "date-time",
"example": "2025-01-08T00:00:00.000Z"
},
"status": {
"type": "string",
"example": "READY"
},
"meta": {
"type": "object",
"properties": {
"origin": {
"type": "string",
"example": "API"
},
"userAgent": {
"type": "string"
}
}
},
"stats": {
"type": "object",
"properties": {
"inputBodyLen": {
"type": "integer",
"example": 2000
},
"rebootCount": {
"type": "integer",
"example": 0
},
"restartCount": {
"type": "integer",
"example": 0
},
"resurrectCount": {
"type": "integer",
"example": 0
},
"computeUnits": {
"type": "integer",
"example": 0
}
}
},
"options": {
"type": "object",
"properties": {
"build": {
"type": "string",
"example": "latest"
},
"timeoutSecs": {
"type": "integer",
"example": 300
},
"memoryMbytes": {
"type": "integer",
"example": 1024
},
"diskMbytes": {
"type": "integer",
"example": 2048
}
}
},
"buildId": {
"type": "string"
},
"defaultKeyValueStoreId": {
"type": "string"
},
"defaultDatasetId": {
"type": "string"
},
"defaultRequestQueueId": {
"type": "string"
},
"buildNumber": {
"type": "string",
"example": "1.0.0"
},
"containerUrl": {
"type": "string"
},
"usage": {
"type": "object",
"properties": {
"ACTOR_COMPUTE_UNITS": {
"type": "integer",
"example": 0
},
"DATASET_READS": {
"type": "integer",
"example": 0
},
"DATASET_WRITES": {
"type": "integer",
"example": 0
},
"KEY_VALUE_STORE_READS": {
"type": "integer",
"example": 0
},
"KEY_VALUE_STORE_WRITES": {
"type": "integer",
"example": 1
},
"KEY_VALUE_STORE_LISTS": {
"type": "integer",
"example": 0
},
"REQUEST_QUEUE_READS": {
"type": "integer",
"example": 0
},
"REQUEST_QUEUE_WRITES": {
"type": "integer",
"example": 0
},
"DATA_TRANSFER_INTERNAL_GBYTES": {
"type": "integer",
"example": 0
},
"DATA_TRANSFER_EXTERNAL_GBYTES": {
"type": "integer",
"example": 0
},
"PROXY_RESIDENTIAL_TRANSFER_GBYTES": {
"type": "integer",
"example": 0
},
"PROXY_SERPS": {
"type": "integer",
"example": 0
}
}
},
"usageTotalUsd": {
"type": "number",
"example": 0.00005
},
"usageUsd": {
"type": "object",
"properties": {
"ACTOR_COMPUTE_UNITS": {
"type": "integer",
"example": 0
},
"DATASET_READS": {
"type": "integer",
"example": 0
},
"DATASET_WRITES": {
"type": "integer",
"example": 0
},
"KEY_VALUE_STORE_READS": {
"type": "integer",
"example": 0
},
"KEY_VALUE_STORE_WRITES": {
"type": "number",
"example": 0.00005
},
"KEY_VALUE_STORE_LISTS": {
"type": "integer",
"example": 0
},
"REQUEST_QUEUE_READS": {
"type": "integer",
"example": 0
},
"REQUEST_QUEUE_WRITES": {
"type": "integer",
"example": 0
},
"DATA_TRANSFER_INTERNAL_GBYTES": {
"type": "integer",
"example": 0
},
"DATA_TRANSFER_EXTERNAL_GBYTES": {
"type": "integer",
"example": 0
},
"PROXY_RESIDENTIAL_TRANSFER_GBYTES": {
"type": "integer",
"example": 0
},
"PROXY_SERPS": {
"type": "integer",
"example": 0
}
}
}
}
}
}
}
}
}
}
```