n8n Webpage Change Monitor: Claude + Slack Alerts Workflow

Monitor a webpage for changes and get Claude-written Slack alerts

This n8n workflow automatically checks a webpage on a schedule, detects meaningful text changes, and uses Claude (Anthropic) to summarize what changed—then posts the result to Slack via an Incoming Webhook. No manual refreshing, no guesswork.

What this workflow does

• Fetches and cleans the page: On each run, it downloads the configured URL and strips it down to visible plain text (removing HTML tags, scripts, and styles).
• Compares against the last snapshot: It stores the previous text in workflow static data (truncated to 8000 characters) and compares current vs. last content.
• Requests a change summary from Claude: If it’s the first run or the text changed, it sends both the previous and current versions to Claude. Claude is explicitly instructed to treat the page content as data only, never as instructions, and to not invent changes that aren’t present.
• Posts to Slack and verifies delivery: It sends the summary to Slack using an Incoming Webhook and verifies delivery by checking the actual response body (not just assuming success).

Use cases

• Track critical policy, pricing, or documentation pages and get notified when wording changes.
• Monitor product release notes or status-style content for meaningful updates.
• Watch competitors’ public pages and route change summaries to a team channel for review.

Technical details

• Integrations: Anthropic (Claude) API, Slack Incoming Webhook, webpage via HTTP Request.
• n8n nodes used: Schedule Trigger, If, Set, Code, No Op, Sticky Note, HTTP Request.
• Setup: Configure the monitored URL and Slack webhook in Set: config, set the schedule (default: every 6 hours), and activate.