Log a transaction

What your assistant is told

Record one transaction (an expense or income) for the calling user. Amounts are ALWAYS integer minor units of the currency — cents for EUR/USD/GBP — never a decimal: €12.34 is amount_minor 1234. category is a category NAME (case-insensitive, e.g. "Groceries") or a category UUID; resolve names with list_categories first if unsure — an unknown name is rejected with the list of valid ones. is_expense true = money out, false = money in. occurred_at_iso is when it happened, and it MUST carry the user's UTC offset ("2026-06-17T09:30:00+03:00", or "…Z" when they really are on UTC) — a timestamp without one is refused, because read back in their own zone it can land in the wrong month; if you don't know their offset, ask. account is the account it happened in (id, alias or IBAN, from list_accounts); omit it only when the user has one account — with two or more an omitted account is refused. currency defaults to the account's. When the line comes from a bank statement, pass the bank's own transaction id as externalId: a line already in the account with that id is refused as a duplicate. Pass a stable idempotencyKey (e.g. a UUID you mint per logical action) so a retry does not double-log. For more than a handful of lines (a whole statement) use log_transactions_batch instead. Returns the created transaction including its id, account and resolved category. Does NOT create categories or accounts — use create_category / create_account for that. TRANSFERS: money the user moved between their OWN accounts (current account → savings, card top-up) is kind "transfer", not an expense or income: leave category out, set isExpense to the direction for THIS account (true = out of it), and pass counterpartAccount when the other account is one of theirs. Transfers stay in the account's history but never count in spending, income or budgets. Payments to other people or companies are standard, never transfers. source says how you captured it — "receipt" when you read it off a receipt photo, otherwise leave it out. A transaction logged here is NOT yet confirmed by a bank statement, and passing externalId does not change that: only log_transactions_batch and attach_statement_line mark a transaction as being on a statement. A one-line statement is therefore better sent through log_transactions_batch, which also checks it against what the user already logged — this tool does not.