docs: backasset is deprecated in v2 and always fails

README.md

@@ -38,9 +38,9 @@ It offers a powerful feature set while keeping unnecessary complexity to a minim
 
 	Smart Contracts can get notified automatically about any relevant events related to their assets. This enables them to make the assets an integral part of their game rather than just a static token.
 
-- **Backing assets with Fungible Tokens**
+- **Backing assets with Fungible Tokens (disabled in v2)**
 
-	Assets can be backed by standard fungible tokens (e.g. EOS / WAX). Those tokens can only be freed by burning the asset, thus allowing dapps to give their asset a guaranteed intrinsic value.
+	Native backing is deprecated. The `backasset` action fails on the v2 contract, so no new asset can be backed. Value already backed is unaffected. Burning an asset still credits its backed tokens to the burner's AtomicAssets token balance, which is claimed with the `withdraw` action as before; the burn itself does not transfer tokens.
 
 - **Powerful Trade Offers**
 

resource/atomicassets.contracts.md

@@ -673,18 +673,16 @@ This action may only be called with the permission of {{owner}}.
 
 ---
 spec_version: "0.2.0"
-title: Backs an asset with tokens
-summary: '{{nowrap payer}} backs the asset with the ID {{nowrap asset_id}} with {{nowrap token_to_back}}'
+title: Deprecated, always fails (formerly: backs an asset with tokens)
+summary: '{{nowrap payer}} attempts to back the asset with the ID {{nowrap asset_id}}; native backing is deprecated and this action fails'
 icon: https://atomicassets.io/image/logo256.png#108AEE3530F4EB368A4B0C28800894CFBABF46534F48345BF6453090554C52D5
 ---
 
 <b>Description:</b>
 <div class="description">
-{{payer}} backs an the asset with the ID {{asset_id}} owned by {{asset_owner}} with {{token_to_back}}.
-{{payer}} must have at least as many tokens in his balance. {{token_to_back}} will be removed from {{payer}}'s balance.
-The tokens backed to this asset can be retreived by burning the asset, in which case the owner at the time of the burn will receive the tokens.
+Native backing is deprecated on the AtomicAssets v2 contract. This action always fails and no tokens are moved.
 
-{{payer}} pays for the full RAM cost of the asset.
+Assets backed before v2 are unaffected. Burning such an asset credits its backed tokens to the burner's AtomicAssets token balance, which is then claimed with the withdraw action; the tokens are not transferred directly by the burn.
 </div>
 
 <b>Clauses:</b>