Real Agent Cases

Prepare and file overdue German VAT returns with Claude Cowork and Claude in Chrome

Source date:
Last verified:
Method:
How we verify

Evidence: Shown on videoThe source includes a video or screen recording of the agent doing the task.

Outcome

From a folder of invoice and receipt PDFs, Claude Cowork prepared quarterly accounts; after the poster logged in to the Elster tax portal, Claude in Chrome found, filled and submitted the Q3 2025 VAT forms.

Agent

Claude Cowork, Claude in Chrome

Prompt Recreated prompt

The source did not publish its exact prompt. This one is our reconstruction from what the source describes.

Not sure how to start? Tell me what you're trying to get done and I'll help you turn it into a clear request.

Goal: Prepare my quarterly accounts from my invoices and receipts, then fill in my VAT return on the German tax portal (Elster).

Quick check first: Which quarters do you need to file?

What I need from you:
- A folder with PDFs of your invoices and receipts
- Your Elster login (you'll log in yourself)

Rules:
- First prepare the accounts for each quarter and show me the totals.
- Once I've logged in, find the right VAT forms and fill them in from those accounts.
- If something is missing or unclear, ask me instead of guessing.
- Don't submit until I've reviewed the figures and said yes.

Output: Quarterly accounts plus the filled VAT forms, ready for my final check.

If any of this is unclear, tell me what you have and I'll help fill the gaps.

You'll know it worked when: the forms match your quarterly totals and you're comfortable pressing submit.

Works best when: you check the numbers yourself before anything is filed.

Source

https://x.com/EastlondonDev/status/2020826097890242582

By Andrew Jefferson (@EastlondonDev) · Published Feb 9, 2026 · Added Oct 16, 2026 · Last verified Oct 16, 2026

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