more fiat and edits

bip-0329.mediawiki

@@ -146,38 +146,45 @@ wallet generating the export, and yet would be hard or impossible
 for importing tools to reconstruct.
 
 All of the following values are optional for exporter to provide,
-but should be given if they are readily on-hand.
+but should be given if they are readily available.
 
 === Transactions ===
 
-* `height`: an integer giving the block height where this fully-confirmed transaction can be found.
-  Omit for transactions that are confirmed by less than 6 blocks, or use value zero.
+* <tt>height</tt>: An integer giving the block height where this fully-confirmed transaction can be found. Omit for transactions that are confirmed by less than 6 blocks, or use value zero.
 
-* `time`: ISO-8601 formated timestamp of the block given by height, preferably in UTC.
-   Example: `2025-01-23T11:40:35-05:00`.
+* <tt>time</tt>: ISO-8601 formatted timestamp of the block given by height, preferably in UTC, although ISO-8601 can represent local times. Example: <tt>2025-01-23T11:40:35-05:00</tt>.
 
-* `fee`: integer giving the number of Satoshis that went to the miner for this transaction.
+* <tt>fee</tt>: Integer giving the number of Satoshis that went to the miner for this transaction.
+
+* <tt>rate</tt>: Exchange rate at time of transaction. This is the fiat value of a Bitcoin at the time of the transaction, based on user preferences for data source. Example: <tt>"rate": { "USD":  105620.00 }</tt>
 
 === Address, Inputs, and Outputs ===
 
-* `keypath`: the data needed to build full descriptor down to the specific address.
-  This extends `origin` with the final two components are are unhardened (in the typical case,
-  assuming BIP-84).  Provide string `/1/123` for `wpkh([d34db33f/84'/0'/0'/1/123])`. If
-  the first character is not `/`, then it should be interpreted as a full descriptior,
-  independant of `origin` (if any).
+* <tt>keypath</tt>: The data needed to build full descriptor down to the specific address.  This extends <tt>origin</tt> with the final two components are are unhardened (in the typical case, assuming BIP-84).  Provide string <tt>/1/123</tt> for <tt>wpkh([d34db33f/84'/0'/0'/1/123])</tt>. If the first character is not <tt>/</tt>, then it should be interpreted as a full descriptor, independant of <tt>origin</tt> (if any).
 
 === Inputs, and Outputs ===
 
-* `value`: integer with the number of Satoshis (`nValue`) of the input or output.
+* <tt>value</tt>: Integer with the number of Satoshis (<tt>nValue</tt>) of the input or output.
+
+* <tt>fmv</tt>: Fair market value of the input/output relative to some other currency, typically fiat. The value should be a mapping, from currency code to decimal number. Example: <tt>"fmv": { "USD":  1233.45 }</tt>. Most situations will have only a single currency value, and it represents the real price of the goods/services expressed in some fiat currency. This is not an exchange *rate*, but an absolute value. By dividing by the <tt>value</tt> (above), it is possible to calculate an effective change rate for the transaction.
+
 
 === Address ===
 
-* `heights`: a list of block heights which contain inputs which deposit to the address.
+* <tt>heights</tt>: a list of block heights which contain inputs which deposit to the address.
+
+== Comment on Types in JSON ==
 
+JSON can serialize a number of basic types, including string, integer
+and boolean (true/false).  Decimal values (<tt>123.45</tt>) can
+also be serialized, but some parsing libraries may interpret them as floating
+point values which is generally not what we want in financial applications.
+When hand-crafting JSON data, be careful not to write <tt>"false"</tt> (with quotes),
+since that is a string with 5 characters and not a boolean.
 
 ==Reference Implementation==
 
-TBD
+* [https://github.com/Labelbase/python-bip329 Python-BIP329 package]
 
 ==References==