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refund-radar

Scan bank statements to detect recurring charges, flag suspicious

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Source Code

refund-radar

Scan bank statements to detect recurring charges, flag suspicious transactions, identify duplicates and fees, draft refund request templates, and generate an interactive HTML audit report.

Triggers

  • "scan my bank statement for refunds"
  • "analyze my credit card transactions"
  • "find recurring charges in my statement"
  • "check for duplicate or suspicious charges"
  • "help me dispute a charge"
  • "generate a refund request"
  • "audit my subscriptions"

Workflow

1. Get Transaction Data

Ask user for bank/card CSV export or pasted text. Common sources:

  • Apple Card: Wallet → Card Balance → Export
  • Chase: Accounts → Download activity → CSV
  • Mint: Transactions → Export
  • Any bank: Download as CSV from transaction history

Or accept pasted text format:

2026-01-03 Spotify -11.99 USD
2026-01-15 Salary +4500 USD

2. Parse and Normalize

Run the parser on their data:

python -m refund_radar analyze --csv statement.csv --month 2026-01

Or for pasted text:

python -m refund_radar analyze --stdin --month 2026-01 --default-currency USD

The parser auto-detects:

  • Delimiter (comma, semicolon, tab)
  • Date format (YYYY-MM-DD, DD/MM/YYYY, MM/DD/YYYY)
  • Amount format (single column or debit/credit)
  • Currency

3. Review Recurring Charges

Tool identifies recurring subscriptions by:

  • Same merchant >= 2 times in 90 days
  • Similar amounts (within 5% or $2)
  • Consistent cadence (weekly, monthly, yearly)
  • Known subscription keywords (Netflix, Spotify, etc.)

Output shows:

  • Merchant name
  • Average amount and cadence
  • Last charge date
  • Next expected charge

4. Flag Suspicious Charges

Tool automatically flags:

Flag Type Trigger Severity
Duplicate Same merchant + amount within 2 days HIGH
Amount Spike > 1.8x baseline, delta > $25 HIGH
New Merchant First time + amount > $30 MEDIUM
Fee-like Keywords (FEE, ATM, OVERDRAFT) + > $3 LOW
Currency Anomaly Unusual currency or DCC LOW

5. Clarify with User

For flagged items, ask in batches of 5-10:

  • Is this charge legitimate?
  • Should I mark this merchant as expected?
  • Do you want a refund template for this?

Update state based on answers:

python -m refund_radar mark-expected --merchant "Costco"
python -m refund_radar mark-recurring --merchant "Netflix"

6. Generate HTML Report

Report saved to ~/.refund_radar/reports/YYYY-MM.html

Copy template.html structure. Sections:

  • Summary: Transaction count, total spent, recurring count, flagged count
  • Recurring Charges: Table with merchant, amount, cadence, next expected
  • Unexpected Charges: Flagged items with severity and reason
  • Duplicates: Same-day duplicate charges
  • Fee-like Charges: ATM fees, FX fees, service charges
  • Refund Templates: Ready-to-copy email/chat/dispute messages

Features:

  • Privacy toggle (blur merchant names)
  • Dark/light mode
  • Collapsible sections
  • Copy buttons on templates
  • Auto-hide empty sections

7. Draft Refund Requests

For each flagged charge, generate three template types:

  • Email: Formal refund request
  • Chat: Quick message for live support
  • Dispute: Bank dispute form text

Three tone variants each:

  • Concise (default)
  • Firm (assertive)
  • Friendly (polite)

Templates include:

  • Merchant name and date
  • Charge amount
  • Dispute reason based on flag type
  • Placeholders for card last 4, reference number

Important: No apostrophes in any generated text.

CLI Reference

# Analyze statement
python -m refund_radar analyze --csv file.csv --month 2026-01

# Analyze from stdin
python -m refund_radar analyze --stdin --month 2026-01 --default-currency CHF

# Mark merchant as expected
python -m refund_radar mark-expected --merchant "Amazon"

# Mark merchant as recurring
python -m refund_radar mark-recurring --merchant "Netflix"

# List expected merchants
python -m refund_radar expected

# Reset learned state
python -m refund_radar reset-state

# Export month data
python -m refund_radar export --month 2026-01 --out data.json

Files Written

Path Purpose
~/.refund_radar/state.json Learned preferences, merchant history
~/.refund_radar/reports/YYYY-MM.html Interactive audit report
~/.refund_radar/reports/YYYY-MM.json Raw analysis data

Privacy

  • No network calls. Everything runs locally.
  • No external APIs. No Plaid, no cloud services.
  • Your data stays on your machine.
  • Privacy toggle in reports. Blur merchant names with one click.

Requirements

  • Python 3.9+
  • No external dependencies

Repository

https://github.com/andreolf/refund-radar