This server wraps a Python change tracker that periodically snapshots web pages and computes structured diffs when content shifts. It exposes five MCP tools: track_url to register a page, check_changes to poll everything you're watching, get_diff to see unified diffs with section-level analysis (which headings changed), get_history to browse past snapshots, and untrack_url to stop monitoring. Under the hood it leans on markgrab for HTML extraction and snapgrab for optional screenshot comparison, storing everything in SQLite. You get line counts, changed sections, and human readable summaries like "3 lines added in Introduction." Reach for it when you need Claude to monitor documentation, competitor pages, or any URL where you care about what shifted between visits, not just that something changed.
Web page change tracking with structured diffs. markgrab + snapgrab integration, MCP native.
from diffgrab import DiffTracker
tracker = DiffTracker()
await tracker.track("https://example.com")
changes = await tracker.check()
for c in changes:
if c.changed:
print(c.summary) # "3 lines added, 1 lines removed in sections: Introduction."
print(c.unified_diff) # Standard unified diff output
await tracker.close()
diffgrab track, check, diff, history, untrackflowchart TD
A["diffgrab track URL"] --> B["Fetch initial snapshot\n(markgrab + snapgrab)"]
B --> C["Store baseline"]
C --> D["diffgrab check"]
D --> E["Fetch current page"]
E --> F{"Content\nhash match?"}
F -->|"changed"| G["Compute structured diff\n+ section analysis"]
F -->|"unchanged"| H["No changes"]
G --> I["📊 DiffResult\nadded / removed / modified"]
pip install diffgrab
Optional extras:
pip install 'diffgrab[cli]' # CLI with click + rich
pip install 'diffgrab[visual]' # Visual diff with snapgrab
pip install 'diffgrab[mcp]' # MCP server with fastmcp
pip install 'diffgrab[all]' # Everything
import asyncio
from diffgrab import DiffTracker
async def main():
tracker = DiffTracker()
# Track a URL (takes initial snapshot)
await tracker.track("https://example.com", interval_hours=12)
# Check for changes
changes = await tracker.check()
for change in changes:
if change.changed:
print(change.summary)
print(change.unified_diff)
# Get diff between specific snapshots
result = await tracker.diff("https://example.com", before_id=1, after_id=2)
# Browse snapshot history
history = await tracker.history("https://example.com", count=20)
# Stop tracking
await tracker.untrack("https://example.com")
await tracker.close()
asyncio.run(main())
from diffgrab import track, check, diff, history, untrack
await track("https://example.com")
changes = await check()
result = await diff("https://example.com")
snaps = await history("https://example.com")
await untrack("https://example.com")
# Track a URL
diffgrab track https://example.com --interval 12
# Check all tracked URLs for changes
diffgrab check
# Check a specific URL
diffgrab check https://example.com
# Show diff between snapshots
diffgrab diff https://example.com
diffgrab diff https://example.com --before 1 --after 3
# View snapshot history
diffgrab history https://example.com --count 20
# Stop tracking
diffgrab untrack https://example.com
Add to your Claude Code MCP config:
{
"mcpServers": {
"diffgrab": {
"command": "diffgrab-mcp",
"args": []
}
}
}
Or with uvx:
{
"mcpServers": {
"diffgrab": {
"command": "uvx",
"args": ["--from", "diffgrab[mcp]", "diffgrab-mcp"]
}
}
}
MCP Tools:
| Tool | Description |
|---|---|
track_url | Register a URL for change tracking |
check_changes | Check tracked URLs for changes |
get_diff | Get structured diff between snapshots |
get_history | Browse snapshot history |
untrack_url | Stop tracking a URL |
Every diff operation returns a DiffResult:
@dataclass
class DiffResult:
url: str # The tracked URL
changed: bool # Whether content changed
added_lines: int # Lines added
removed_lines: int # Lines removed
changed_sections: list[str] # Markdown headings with changes
unified_diff: str # Standard unified diff
summary: str # Human-readable summary
before_snapshot_id: int | None # DB ID of older snapshot
after_snapshot_id: int | None # DB ID of newer snapshot
before_timestamp: str # When older snapshot was taken
after_timestamp: str # When newer snapshot was taken
Snapshots are stored in SQLite at ~/.local/share/diffgrab/diffgrab.db (auto-created). Custom path:
tracker = DiffTracker(db_path="/path/to/custom.db")
| Package | Role | PyPI |
|---|---|---|
| markgrab | HTML/YouTube/PDF/DOCX to markdown | pip install markgrab |
| snapgrab | URL to screenshot + metadata | pip install snapgrab |
| docpick | OCR + LLM document extraction | pip install docpick |
| feedkit | RSS feed collection | pip install feedkit |
| diffgrab | Web page change tracking | pip install diffgrab |
| browsegrab | Browser agent for LLMs | Coming soon |
Part of the QuartzUnit ecosystem — composable Python libraries for data collection, extraction, search, and AI agent safety.