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transactionsConcept

Categorization

Categorization is the decision of which account absorbed the other side of a bank transaction's money, turning a raw imported fact into a real, balanced journal entry.

In short

Naming the other half of a transaction. The bank side is already known; categorizing says "this $120.50 was Materials," and BalanceMCP posts the balanced entry automatically. It can be split across several accounts, previews before it writes anything, and skips (rather than fails) a whole batch over one bad line.

Also called: categorizing a transaction, coding a transaction

You might have arrived here asking

Categorization is the decision of which account absorbed the other side of a bank transaction. The bank already stated the date, the amount and the description; what remains unknown is where the money went in accounting terms, and naming that account is the whole of the act.

It is a judgement, not a lookup, which is the reason it is the part an AI assistant is genuinely useful for and the part it can be wrong about. The same hardware-store charge is job materials for a builder and office supplies for an accountant, and nothing in the transaction itself distinguishes them.

Its output is a journal entry, so everything true of entries is true of the result: it balances or it is rejected, it cannot be edited afterwards, and undoing it means posting a reversal. A categorization is not a label attached to a transaction, it is a permanent record created from one.

One transaction can name several accounts at once when the pieces sum exactly to the total, which is a split rather than several transactions. What categorization never does is create money — it decides where existing money went.

What people get wrong

  • Assuming a saved rule will auto-categorize the next matching transaction — rules are stored but not applied automatically in the current version.
  • Assuming split amounts don't need to add up exactly — they're checked arithmetically and rejected if they don't sum to the transaction's total.
  • Approving a large batch's preview reflexively without a glance — catching an obviously wrong pattern in the preview costs nothing; catching it after confirming means reversing entries instead.

Common questions

What happens if a saved rule matches a new transaction?
Nothing automatic — in the current version, saved rules are stored but not applied. The transaction still shows up unposted and still needs to be categorized directly.
Can one transaction be split across multiple accounts?
Yes, as long as the split amounts sum exactly to the transaction's total — categorized as one entry with multiple lines, not several separate transactions.

Machine-readable: /api/knowledge/concept:categorization