Signal Lab — Apify API examples for price tracking, keyword research, RAG, transcripts, jobs, menus, and Reddit

Small copy-paste examples for public Signal Lab Actors on the Apify Store. The goal is to make common automation jobs easy to test from the Store, Apify API, schedules, webhooks, Make, n8n, or MCP.

Pricing can change. Use each Actor's live Pricing tab in Apify as the source of truth.

Official MCP Registry

Signal Lab is published in the Official Model Context Protocol Registry as:

io.github.VZezelin/signal-lab-apify-tools

Registry search: https://registry.modelcontextprotocol.io/?q=io.github.VZezelin%2Fsignal-lab-apify-tools

The registered remote uses Apify's hosted Streamable HTTP MCP endpoint and exposes a focused set of Signal Lab tools for Amazon price tracking, Google Autocomplete keywords, website-to-Markdown/RAG, YouTube transcripts, Reddit search/comments, public job postings, and restaurant menus.

{
  "mcpServers": {
    "signal-lab": {
      "url": "https://mcp.apify.com?tools=signal_lab/amazon-price-tracker,signal_lab/google-autocomplete-keywords,signal_lab/website-to-markdown-crawler,signal_lab/youtube-transcript-scraper,signal_lab/reddit-search-comments,signal_lab/job-vacancy-scraper,signal_lab/restaurant-menu-extractor"
    }
  }
}

Apify handles the MCP connection and authentication flow. Actor pricing remains defined by each Actor's live Apify Pricing tab.

Buyer-intent API guides

Amazon Price Tracker API — ASIN monitoring and price-drop alerts
Google Autocomplete API — buyer-intent keyword research
Website to Markdown API — clean RAG and LLM ingestion
Job Posting Scraper API — title, salary, company, and location
Restaurant Menu Scraper API — items, prices, sections, and descriptions
Reddit Scraper API — search posts and comments

1. Amazon Price Tracker API — track an ASIN and build price-drop alerts

Actor: https://apify.com/signal_lab/amazon-price-tracker

Useful for:

Amazon price tracking by ASIN/product URL
price history pipelines
price-change and price-drop alerts
scheduled competitor monitoring

Run through the Apify API:

curl -X POST \
  "https://api.apify.com/v2/acts/signal_lab~amazon-price-tracker/runs" \
  -H "Authorization: Bearer $APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "productUrls": ["https://www.amazon.com/dp/0132350882"],
    "emitOnlyChanges": false,
    "proxyConfiguration": {"useApifyProxy": false},
    "maxItems": 10
  }'

For alerts, run it on an Apify schedule and connect a webhook/Make/n8n flow to the resulting dataset.

2. Google Autocomplete API — buyer-intent keyword suggestions

Actor: https://apify.com/signal_lab/google-autocomplete-keywords

Useful for:

Google Autocomplete keyword research
commercial modifiers such as cost, pricing, free, alternative, and API
country/language-specific long-tail research
programmatic SEO and demand discovery

curl -X POST \
  "https://api.apify.com/v2/acts/signal_lab~google-autocomplete-keywords/runs" \
  -H "Authorization: Bearer $APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "queries": ["google autocomplete api"],
    "language": "en",
    "country": "us",
    "expandAlphabet": false,
    "includeQuestions": false,
    "maxResults": 20
  }'

3. Website to Markdown API — clean pages for RAG and LLM ingestion

Actor: https://apify.com/signal_lab/website-to-markdown-crawler

Useful for:

website-to-Markdown conversion
clean RAG/LLM source documents
headings, links, metadata, and structured page extraction
one-page API calls or bounded website crawls

curl -X POST \
  "https://api.apify.com/v2/acts/signal_lab~website-to-markdown-crawler/runs" \
  -H "Authorization: Bearer $APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "startUrls": [{"url": "https://example.com"}],
    "maxPages": 1,
    "maxDepth": 0,
    "sameDomainOnly": true,
    "useSitemaps": false,
    "respectRobotsTxt": true
  }'

4. YouTube Transcript API — captions, timestamps, and metadata

Actor: https://apify.com/signal_lab/youtube-transcript-scraper

Useful for:

public YouTube transcripts
timestamped caption segments
RAG and semantic search
research, summarization, and indexing workflows

Open the Actor's Store page for the current input schema and live pricing, then run it from the UI, API, schedule, or MCP.

MCP / AI-agent usage

The Official MCP Registry entry above is the canonical discovery record for this Signal Lab tool bundle. You can also configure the same Apify-hosted endpoint directly in MCP-compatible clients.

After authentication, an agent can request tasks such as:

“Track this Amazon ASIN and return the current price.”
“Find Google Autocomplete suggestions for this buyer-intent keyword.”
“Convert this page to clean Markdown for a RAG pipeline.”
“Get this public YouTube transcript with timestamps.”
“Search Reddit for recent product feedback and return source URLs.”
“Extract structured fields from this public job posting.”
“Extract menu items and prices from this restaurant page.”

More Signal Lab Actors

Browse the public portfolio: https://apify.com/signal_lab

Use public data responsibly and follow the target site's terms, privacy rules, copyright requirements, and applicable law.

Signal Lab — Apify API examples for price tracking, keyword research, RAG, transcripts, jobs, menus, and Reddit