Invoice Organizer Skill for Claude

Invoice Organizer

Bulk-categorize a CSV of invoices or receipts, detect duplicates, and produce a tax-ready monthly summary.

Table of Contents

• Keywords
• Quick Start
• Core Workflows
• Tools
• Reference Guides
• Templates
• Best Practices

Keywords

invoice, invoices, receipt, receipts, expense, expenses, bookkeeping, accounting, tax, tax prep, categorization, vendor, reimbursement, monthly summary

Clarify First

Before categorizing, confirm these inputs. If any is unknown or vague, ASK — do not assume:

• [ ] Receipt CSV fields — date, vendor, description, amount drive categorization and duplicate detection
• [ ] Tax bucket scheme — US Schedule C vs UK self-employment vs generic sets which categories the summary maps to
• [ ] Recurring-vendor rules — known vendor→category mappings to seed category_rules.json and cut the uncategorized bucket

Stop rule: ask only the 2-3 that most change the output. If the user says "just draft it," proceed and list your assumptions at the top of the artifact.

Quick Start

Categorize 200 Receipts in 1 Minute

• Export receipts from your bank or expense tool as a CSV with columns: date,vendor,description,amount,currency
• Run:

   python scripts/invoice_categorizer.py receipts.csv

• Review the categorized output and override anything wrong via the rules file
• Export the monthly summary for handoff to your accountant

Core Workflows

Workflow 1: Monthly Bookkeeping

Goal: Convert a month of unstructured receipts into a categorized, tax-ready summary in under 10 minutes.

Steps:

• Export receipts as CSV from your bank, card, or expense tool
• Run: python scripts/invoice_categorizer.py receipts.csv
• Review the uncategorized bucket — these need rules added or manual override
• Add rules to assets/category_rules.json for any recurring vendors
• Re-run; uncategorized count should drop each month as the rules file grows
• Drop the monthly summary into assets/monthly_summary_template.md

Expected Output: Categorized expense list + monthly totals by category + duplicate-suspect list.

Time Estimate: 10 minutes/month after initial rules are seeded.

Workflow 2: Duplicate Detection

Goal: Catch double-entered receipts before they reach the books.

Steps:

• Run: python scripts/invoice_categorizer.py receipts.csv --json
• Inspect the duplicates_suspected list
• Confirm whether each is a true duplicate (same charge entered twice) or a coincidence (same amount on different days at different vendors)
• Remove confirmed duplicates from the source CSV; re-run

Expected Output: Cleaned CSV with no duplicate rows.

Time Estimate: 2-3 minutes per month.

Workflow 3: Vendor Spend Review

Goal: Find spend creep — vendors whose monthly total grew significantly without you noticing.

Steps:

• Run categorizer for the last 3-6 months separately
• Compare per-vendor totals month-over-month
• Flag any vendor where total grew > 25% with no obvious business reason
• Either renegotiate, switch, or accept; revisit quarterly

Expected Output: Vendor-spend trend list with flagged growth.

Time Estimate: 15 minutes per quarter.

Tools

invoice_categorizer.py

Reads a CSV of receipts/invoices and:

• Categorizes each row by vendor + description against rules in assets/category_rules.json (extensible)
• Aggregates totals per category and per vendor
• Detects likely duplicates (same vendor + amount within 3 days)
• Flags uncategorized items for manual review

# Human-readable summary
python scripts/invoice_categorizer.py receipts.csv

# JSON for programmatic use
python scripts/invoice_categorizer.py receipts.csv --json

# Use a custom rules file
python scripts/invoice_categorizer.py receipts.csv --rules my-rules.json

Expected CSV columns: date, vendor, description, amount (currency optional)

Date formats accepted: YYYY-MM-DD, MM/DD/YYYY, DD/MM/YYYY

Reference Guides

• references/expense_categorization_guide.md — Standard expense categories, common tax buckets (US Schedule C, UK self-employment, generic), how to map vendors to categories

Templates

• assets/category_rules.json — Default rules; extend with your recurring vendors
• assets/monthly_summary_template.md — Format for handing the monthly summary to an accountant

Best Practices

• Categorize monthly, not annually. Annual catch-up bookkeeping always misses receipts and produces guess-categorization.
• Grow the rules file over time. First month: 30% uncategorized. Sixth month: < 5%. The compounding return on rule-writing is high.
• Keep evidence. Categorization is bookkeeping; receipts (PDFs, photos) are tax evidence. Store separately from this script's output.
• Don't trust auto-categorization for tax filing. Use it for prep; have a human (you or your accountant) sign off before filing.
• Currency consistency. If you have multi-currency receipts, convert at month-end FX rate before this script; it does not handle FX.

Integration Points

• Pairs with finance/ skills for budgeting and forecasting
• Feeds into c-level-advisor/cs-cfo-advisor cash-flow workflows
• Used by solo-founder persona for monthly close