Track co-founder costs and who owes whom by telling Claude what you paid
His hackathon app splits costs between founders, shows who owes whom with a pay button, checks what happens to shared assets if a founder vanishes, and has an MCP server so telling Claude "I paid 25 for Supabase" logs the expense.
Source
@mwarcholinski on X · 2026-10-18
Written in our own words. Credit to the original author. Link checked 2026-10-18.
What they did
His hackathon app splits costs between founders, shows who owes whom with a pay button, checks what happens to shared assets if a founder vanishes, and has an MCP server so telling Claude "I paid 25 for Supabase" logs the expense.
Result (as claimed)
Shipped during a hackathon week.
Tools they used
Cost: Pricing depends on the tools you pick; check each official pricing page.
Set it up
Gather the documents
Collect statements, bills, invoices or tax documents for the period you want reviewed.
Ask for an audit, not actions
Have Claude list findings, amounts and suggested next steps before it does anything.
Approve each action
Approve cancellations, disputes or payments one at a time. Never give an agent open-ended access to move money.
Track the result
Record what changed and what you saved so you can check it next month. This is not financial advice.
Copy the full setup prompt
Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.
You are helping me set up this AI use case end to end in Claude Code. Goal: Track co-founder costs and who owes whom by telling Claude what you paid What the original author did: His hackathon app splits costs between founders, shows who owes whom with a pay button, checks what happens to shared assets if a founder vanishes, and has an MCP server so telling Claude "I paid 25 for Supabase" logs the expense. Reported result (as claimed by the author): Shipped during a hackathon week. Source: https://x.com/mwarcholinski/status/2111762713559056566 Tools they used: Claude, Supabase Category: Money Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Codex. Goal: Track co-founder costs and who owes whom by telling Claude what you paid What the original author did: His hackathon app splits costs between founders, shows who owes whom with a pay button, checks what happens to shared assets if a founder vanishes, and has an MCP server so telling Claude "I paid 25 for Supabase" logs the expense. Reported result (as claimed by the author): Shipped during a hackathon week. Source: https://x.com/mwarcholinski/status/2111762713559056566 Tools they used: Claude, Supabase Category: Money Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Grok Bot. Goal: Track co-founder costs and who owes whom by telling Claude what you paid What the original author did: His hackathon app splits costs between founders, shows who owes whom with a pay button, checks what happens to shared assets if a founder vanishes, and has an MCP server so telling Claude "I paid 25 for Supabase" logs the expense. Reported result (as claimed by the author): Shipped during a hackathon week. Source: https://x.com/mwarcholinski/status/2111762713559056566 Tools they used: Claude, Supabase Category: Money Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
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