diff --git a/beancount_format.py b/beancount_format.py
index b895124..6b8d196 100644
--- a/beancount_format.py
+++ b/beancount_format.py
@@ -112,13 +112,9 @@ def format_posting_with_cost(
         # Returns: {
         #     "account": "Expenses:Food",
         #     "amount": "200000 SATS {100.00 EUR}",
-        #     "meta": {
-        #         "fiat-currency": "EUR",
-        #         "fiat-amount": "100.00",
-        #         "sats-equivalent": "200000",
-        #         "exchange-rate": "2000.00"
-        #     }
+        #     "meta": {}
         # }
+        # Note: All fiat/exchange rate info is in the cost syntax "{100.00 EUR}"
     """
     # Build amount string with cost basis
     if fiat_currency and fiat_amount and fiat_amount > 0:
@@ -129,23 +125,10 @@ def format_posting_with_cost(
         # No cost basis: "200000 SATS"
         amount_str = f"{amount_sats} SATS"
 
-    # Build metadata
+    # Build metadata (only include explicitly passed metadata, not redundant fiat info)
+    # The cost syntax "{69.00 EUR}" already contains all fiat/exchange rate information
     posting_meta = metadata or {}
 
-    if fiat_currency and fiat_amount and fiat_amount > 0:
-        # Store fiat information in metadata for easy access
-        posting_meta["fiat-currency"] = fiat_currency
-        posting_meta["fiat-amount"] = str(abs(fiat_amount))
-        posting_meta["sats-equivalent"] = str(abs(amount_sats))
-
-        # Calculate exchange rate (sats per fiat unit)
-        exchange_rate = abs(amount_sats) / abs(fiat_amount)
-        posting_meta["exchange-rate"] = f"{exchange_rate:.2f}"
-
-        # Calculate BTC rate (fiat per BTC)
-        btc_rate = abs(fiat_amount) / abs(amount_sats) * 100_000_000
-        posting_meta["btc-rate"] = f"{btc_rate:.2f}"
-
     return {
         "account": account,
         "amount": amount_str,
@@ -262,11 +245,11 @@ def format_expense_entry(
     ]
 
     # Build entry metadata
+    # Note: created-via is redundant with #expense-entry tag
+    # Note: is-equity is redundant with account name (Equity vs Liabilities:Payable) and tags
     entry_meta = {
         "user-id": user_id,
-        "source": "castle-api",
-        "created-via": "expense_entry",
-        "is-equity": "true" if is_equity else "false"
+        "source": "castle-api"
     }
 
     # Build links
@@ -342,11 +325,11 @@ def format_receivable_entry(
         )
     ]
 
+    # Note: created-via is redundant with #receivable-entry tag
+    # Note: debtor-user-id is the same as user-id for receivables (redundant)
     entry_meta = {
         "user-id": user_id,
-        "source": "castle-api",
-        "created-via": "receivable_entry",
-        "debtor-user-id": user_id
+        "source": "castle-api"
     }
 
     links = []
@@ -436,12 +419,11 @@ def format_payment_entry(
             )
         ]
 
+    # Note: created-via is redundant with #lightning-payment tag
+    # Note: payer/payee can be inferred from transaction direction and accounts
     entry_meta = {
         "user-id": user_id,
-        "source": "lightning_payment",
-        "created-via": "payment_entry",
-        "payer-user-id": user_id if not is_payable else "castle",
-        "payee-user-id": user_id if is_payable else "castle"
+        "source": "lightning_payment"
     }
 
     if payment_hash:
@@ -527,9 +509,9 @@ def format_revenue_entry(
         )
     ]
 
+    # Note: created-via is redundant with #revenue-entry tag
     entry_meta = {
-        "source": "castle-api",
-        "created-via": "revenue_entry"
+        "source": "castle-api"
     }
 
     links = []