<pre>
  BIP: 382
  Layer: Applications
  Title: Segwit Output Script Descriptors
  Author: Pieter Wuille <pieter@wuille.net>
          Andrew Chow <andrew@achow101.com>
  Comments-Summary: No comments yet.
  Comments-URI: https://github.com/bitcoin/bips/wiki/Comments:BIP-0382
  Status: Draft
  Type: Informational
  Created: 2021-06-27
  License: BSD-2-Clause
</pre>

==Abstract==

This document specifies <tt>wpkh()</tt>, and <tt>wsh()</tt> output script descriptors.
<tt>wpkh()</tt> descriptors take a key and produces a P2WPKH output script.
<tt>wsh()</tt> descriptors take a script and produces a P2WSH output script.

==Copyright==

This BIP is licensed under the BSD 2-clause license.

==Motivation==

Segregated Witness added 2 additional standard output script formats: P2WPKH and P2WSH.
These expressions allow specifying those formats as a descriptor.

==Specification==

Two new script expressions are defined: <tt>wpkh()</tt>, and <tt>wsh()</tt>.

===<tt>wpkh()</tt>===

The <tt>wpkh(KEY)</tt> expression can be used as a top level expression, or inside of a <tt>sh()</tt> descriptor.
It takes a single key expression as an argument and produces a P2WPKH output script.
Only keys which are/has compressed public keys can be contained in a <tt>wpkh()</tt> expression.

The output script produced is:
<pre>
OP_0 <KEY_hash160>
</pre>

===<tt>wsh()</tt>===

The <tt>wsh(SCRIPT)</tt> expression can be used as a top level expression, or inside of a <tt>sh()</tt> descriptor.
It takes a single script expression as an argument and produces a P2WSH output script.
<tt>wsh()</tt> expressions also create a witnessScript which is required in order to spend outputs which use its output script.
This redeemScript is the output script produced by the <tt>SCRIPT</tt> argument to <tt>wsh()</tt>.
Any key expression found in any script expression contained by a <tt>wsh()</tt> expression must only produce compressed public keys.

The output script produced is:
<pre>
OP_0 <SCRIPT_sha256>
</pre>

==Test Vectors==

TBD

==Backwards Compatibility==

<tt>wpkh()</tt>, and <tt>wsh()</tt> descriptors use the format and general operation specified in [[bip-0380.mediawiki|380]].
As these are a wholly new descriptors, they are not compatible with any implementation.
However the scripts produced are standard scripts so existing software are likely to be familiar with them.

==Reference Implementation==

<tt>wpkh()</tt>, and <tt>wsh()</tt> descriptors have been implemented in Bitcoin Core since version 0.17.
