tool_monitor_changes
Monitor web page changes by comparing content hashes to detect modifications over time, providing change detection reports for tracking updates.
Instructions
Check if a page has changed.
Tracks content modifications over time.
Args: url: URL to monitor. previous_hash: Previous content hash to compare against.
Returns: Change detection report with content hash.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | ||
| previous_hash | No |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Implementation Reference
- src/devlens/tools/advanced.py:226-270 (handler)The actual implementation of the monitor_changes logic, which fetches the page and performs content comparison.
async def monitor_changes(url: str, previous_content: str | None = None) -> str: """Check if a page has changed since last check. Args: url: URL to monitor. previous_content: Previous content hash or snippet to compare. Returns: Change detection report. Example: >>> changes = await monitor_changes("https://example.com", previous_hash) """ try: doc = await _scraper.fetch(url, retry=1) current_content = doc.content # Generate content hash import hashlib current_hash = hashlib.sha256(current_content.encode()).hexdigest()[:16] report_lines = [ f"# Change Monitor: {doc.title}\n", f"> URL: {url}\n", f"> Checked: {doc.fetched_at.strftime('%Y-%m-%d %H:%M:%S')}\n", "\n## Status\n", ] if previous_content: if previous_content == current_hash: report_lines.append("✓ **No changes detected**\n") else: report_lines.append("⚠️ **Content has changed**\n") report_lines.append(f"\n- Previous hash: `{previous_content}`\n") report_lines.append(f"- Current hash: `{current_hash}`\n") else: report_lines.append("ℹ️ **First check - baseline established**\n") report_lines.append(f"\n- Content hash: `{current_hash}`\n") # Add content preview report_lines.append("\n## Current Content Preview\n") preview = current_content[:500].strip() report_lines.append(f"{preview}...\n") - src/devlens/server.py:162-175 (registration)The MCP tool registration and wrapper function tool_monitor_changes that delegates to the monitor_changes helper.
@mcp.tool() async def tool_monitor_changes(url: str, previous_hash: str | None = None) -> str: """Check if a page has changed. Tracks content modifications over time. Args: url: URL to monitor. previous_hash: Previous content hash to compare against. Returns: Change detection report with content hash. """ return await monitor_changes(url, previous_hash)