About Diffgrab
Diffgrab tracks web page changes for developers and researchers monitoring updates. It produces structured diffs with section-level analysis and stores snapshot history in SQLite, with optional visual comparison through snapgrab.
Key features
- 01Detect changes in web page content
- 02Generate unified diffs and section analysis
- 03Summarize changes in readable form
- 04Store snapshot history in SQLite
- 05Compare screenshots with optional visual diff
Use cases
- 01Monitor pages for newly published content
- 02See which sections and lines changed
- 03Review earlier versions of a page
- 04Compare visual changes between screenshots
MCP support
Diffgrab's MCP server provides five tools to register URLs, check for changes, retrieve structured diffs, browse snapshot history, and stop tracking.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEdiffgrab
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()
Features
- Change detection — track any URL, detect content changes via content hashing
- Structured diffs — unified diff + section-level analysis (which headings changed)
- Human-readable summaries — "5 lines added, 2 removed in sections: Intro, Methods"
- Snapshot history — SQLite storage, browse past versions of any page
- markgrab powered — HTML/YouTube/PDF/DOCX extraction via markgrab
- Visual diff — optional screenshot comparison via snapgrab
- MCP server — 5 tools for Claude Code / MCP clients
- CLI included —
diffgrab track,check,diff,history,untrack
How It Works
flowchart 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"]
Install
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
Usage
Python API
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())
Convenience Functions
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")
CLI
# 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
MCP Server
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 |
DiffResult
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
Storage
Snapshots are stored in SQLite at ~/.local/share/diffgrab/diffgrab.db (auto-created). Custom path:
tracker = DiffTracker(db_path="/path/to/custom.db")
QuartzUnit Ecosystem
| 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 |
Used in
- newswatch — RSS news monitoring pipeline (feedkit → markgrab → embgrep → diffgrab)
- watchdeck — Web page monitoring with visual diffs and safety guards
License
Part of the QuartzUnit ecosystem — composable Python libraries for data collection, extraction, search, and AI agent safety.
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