diff --git a/acceptance/python/src/conftest.py b/acceptance/python/src/conftest.py
index 34e8a3f..8583969 100644
--- a/acceptance/python/src/conftest.py
+++ b/acceptance/python/src/conftest.py
@@ -36,20 +36,22 @@ FULFILL_SCRIPT = \
     When I verify the 'houses' has a signature in 'data.signature' by 'Alice'
     Then print the string 'ok'"""
 
-HOUSE_ASSETS = {
-    "data": {
-        "houses": [
-            {
-                "name": "Harry",
-                "team": "Gryffindor",
-            },
-            {
-                "name": "Draco",
-                "team": "Slytherin",
-            }
-        ],
+HOUSE_ASSETS = [
+    {
+        "data": {
+            "houses": [
+                {
+                    "name": "Harry",
+                    "team": "Gryffindor",
+                },
+                {
+                    "name": "Draco",
+                    "team": "Slytherin",
+                }
+            ],
+        }
     }
-}
+]
 
 ZENROOM_DATA = {
     'also': 'more data'
diff --git a/acceptance/python/src/test_basic.py b/acceptance/python/src/test_basic.py
index 5e09085..65d08de 100644
--- a/acceptance/python/src/test_basic.py
+++ b/acceptance/python/src/test_basic.py
@@ -44,13 +44,13 @@ def test_basic():
     # ## Alice registers her bike in Planetmint
     # Alice has a nice bike, and here she creates the "digital twin"
     # of her bike.
-    bike = {'data': {'bicycle': {'serial_number': 420420}}}
+    bike = [{'data': {'bicycle': {'serial_number': 420420}}}]
 
     # She prepares a `CREATE` transaction...
     prepared_creation_tx = bdb.transactions.prepare(
             operation='CREATE',
             signers=alice.public_key,
-            asset=bike)
+            assets=bike)
 
     # ... and she fulfills it with her private key.
     fulfilled_creation_tx = bdb.transactions.fulfill(
@@ -98,7 +98,7 @@ def test_basic():
     # Now that all the elements are set, she creates the actual transaction...
     prepared_transfer_tx = bdb.transactions.prepare(
             operation='TRANSFER',
-            asset=transfer_asset,
+            assets=transfer_asset,
             inputs=transfer_input,
             recipients=bob.public_key)
 
diff --git a/acceptance/python/src/test_divisible_asset.py b/acceptance/python/src/test_divisible_asset.py
index 1967237..6d7db5f 100644
--- a/acceptance/python/src/test_divisible_asset.py
+++ b/acceptance/python/src/test_divisible_asset.py
@@ -68,7 +68,7 @@ def test_divisible_assets():
         operation='CREATE',
         signers=alice.public_key,
         recipients=[([bob.public_key], 10)],
-        asset=bike_token)
+        assets=bike_token)
 
     # She fulfills and sends the transaction.
     fulfilled_token_tx = bdb.transactions.fulfill(
@@ -108,7 +108,7 @@ def test_divisible_assets():
     # amount he wants to use to Alice.
     prepared_transfer_tx = bdb.transactions.prepare(
         operation='TRANSFER',
-        asset=transfer_asset,
+        assets=transfer_asset,
         inputs=transfer_input,
         recipients=[([alice.public_key], 3), ([bob.public_key], 7)])
 
@@ -155,7 +155,7 @@ def test_divisible_assets():
     # to spend all his tokens
     prepared_transfer_tx = bdb.transactions.prepare(
         operation='TRANSFER',
-        asset=transfer_asset,
+        assets=transfer_asset,
         inputs=transfer_input,
         recipients=[([alice.public_key], 8)])
 
diff --git a/acceptance/python/src/test_double_spend.py b/acceptance/python/src/test_double_spend.py
index 8f8fab9..48eca3b 100644
--- a/acceptance/python/src/test_double_spend.py
+++ b/acceptance/python/src/test_double_spend.py
@@ -26,7 +26,7 @@ def test_double_create():
             bdb.transactions.prepare(
                 operation='CREATE',
                 signers=alice.public_key,
-                asset={'data': {'uuid': str(uuid4())}}),
+                assets={'data': {'uuid': str(uuid4())}}),
             private_keys=alice.private_key)
 
     def send_and_queue(tx):
diff --git a/acceptance/python/src/test_multiple_owners.py b/acceptance/python/src/test_multiple_owners.py
index e60c63a..6400477 100644
--- a/acceptance/python/src/test_multiple_owners.py
+++ b/acceptance/python/src/test_multiple_owners.py
@@ -57,7 +57,7 @@ def test_multiple_owners():
         operation='CREATE',
         signers=alice.public_key,
         recipients=(alice.public_key, bob.public_key),
-        asset=dw_asset)
+        assets=dw_asset)
 
     # Now they both sign the transaction by providing their private keys.
     # And send it afterwards.
@@ -101,7 +101,7 @@ def test_multiple_owners():
     # Now they create the transaction...
     prepared_transfer_tx = bdb.transactions.prepare(
         operation='TRANSFER',
-        asset=transfer_asset,
+        assets=transfer_asset,
         inputs=transfer_input,
         recipients=carol.public_key)
 
diff --git a/acceptance/python/src/test_naughty_strings.py b/acceptance/python/src/test_naughty_strings.py
index 423ae01..be7438c 100644
--- a/acceptance/python/src/test_naughty_strings.py
+++ b/acceptance/python/src/test_naughty_strings.py
@@ -32,7 +32,7 @@ naughty_strings = blns.all()
 
 
 # This is our base test case, but we'll reuse it to send naughty strings as both keys and values.
-def send_naughty_tx(asset, metadata):
+def send_naughty_tx(assets, metadata):
     # ## Set up a connection to Planetmint
     # Check [test_basic.py](./test_basic.html) to get some more details
     # about the endpoint.
@@ -45,7 +45,7 @@ def send_naughty_tx(asset, metadata):
     prepared_transaction = bdb.transactions.prepare(
         operation='CREATE',
         signers=alice.public_key,
-        asset=asset,
+        assets=assets,
         metadata=metadata)
 
     # She fulfills the transaction
@@ -86,16 +86,16 @@ def send_naughty_tx(asset, metadata):
 @pytest.mark.parametrize("naughty_string", naughty_strings, ids=naughty_strings)
 def test_naughty_keys(naughty_string):
 
-    asset = {'data': {naughty_string: 'nice_value'}}
+    assets = [{'data': {naughty_string: 'nice_value'}}]
     metadata = {naughty_string: 'nice_value'}
 
-    send_naughty_tx(asset, metadata)
+    send_naughty_tx(assets, metadata)
 
 
 @pytest.mark.parametrize("naughty_string", naughty_strings, ids=naughty_strings)
 def test_naughty_values(naughty_string):
 
-    asset = {'data': {'nice_key': naughty_string}}
+    assets = [{'data': {'nice_key': naughty_string}}]
     metadata = {'nice_key': naughty_string}
 
-    send_naughty_tx(asset, metadata)
+    send_naughty_tx(assets, metadata)
diff --git a/acceptance/python/src/test_stream.py b/acceptance/python/src/test_stream.py
index c6d037b..b9f2161 100644
--- a/acceptance/python/src/test_stream.py
+++ b/acceptance/python/src/test_stream.py
@@ -93,7 +93,7 @@ def test_stream():
                 bdb.transactions.prepare(
                     operation='CREATE',
                     signers=alice.public_key,
-                    asset={'data': {'uuid': str(uuid4())}}),
+                    assets=[{'data': {'uuid': str(uuid4())}}]),
                 private_keys=alice.private_key)
         # We don't want to wait for each transaction to be in a block. By using
         # `async` mode, we make sure that the driver returns as soon as the
diff --git a/acceptance/python/src/test_zenroom.py b/acceptance/python/src/test_zenroom.py
index 2829fab..97cd440 100644
--- a/acceptance/python/src/test_zenroom.py
+++ b/acceptance/python/src/test_zenroom.py
@@ -58,7 +58,7 @@ condition_script_zencode, zenroom_data, zenroom_house_assets):
 
     token_creation_tx = {
         'operation': 'CREATE',
-        'asset': zenroom_house_assets,
+        'assets': zenroom_house_assets,
         'metadata': None,
         'outputs': (output,),
         'inputs': (input_,),
diff --git a/docs/root/source/installation/api/http-samples/api-index-response.http b/docs/root/source/installation/api/http-samples/api-index-response.http
index 7ba7be8..601f9ef 100644
--- a/docs/root/source/installation/api/http-samples/api-index-response.http
+++ b/docs/root/source/installation/api/http-samples/api-index-response.http
@@ -4,7 +4,7 @@ Content-Type: application/json
 {
   "assets": "/assets/",
   "blocks": "/blocks/",
-  "docs": "https://docs.planetmint.com/projects/server/en/v0.9.0/http-client-server-api.html",
+  "docs": "https://docs.planetmint.com/projects/server/en/v0.9.1/http-client-server-api.html",
   "metadata": "/metadata/",
   "outputs": "/outputs/",
   "streams": "ws://localhost:9985/api/v1/streams/valid_transactions",
diff --git a/docs/root/source/installation/api/http-samples/get-block-response.http b/docs/root/source/installation/api/http-samples/get-block-response.http
index 168c60c..01dffd9 100644
--- a/docs/root/source/installation/api/http-samples/get-block-response.http
+++ b/docs/root/source/installation/api/http-samples/get-block-response.http
@@ -5,15 +5,17 @@ Content-Type: application/json
   "height": 1,
   "transactions": [
     {
-      "asset": {
-        "data": {
-          "msg": "Hello Planetmint!"
+      "assets": [
+        {
+          "data": {
+            "msg": "Hello Planetmint!"
+          }
         }
-      },
-      "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2",
+      ],
+      "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac",
       "inputs": [
         {
-          "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUBcdRj6EnG3MPl47m3XPd1HNfe7q3WL4T6MewNNnat33UvzVnPHo_vossv57M7L064VwrYMLGp097H7IeHpDngK",
+          "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUCWcUaLa2U-nkmZ6oYj14aeV6B4TJH2NvZ8k2ZTwcGiaiCGXDQT2dEPfMCFwM8lwSousafCu4c7EgVZ1GzUDjsN",
           "fulfills": null,
           "owners_before": [
             "4K9sWUMFwTgaDGPfdynrbxWqWS6sWmKbZoTjxLtVUibD"
diff --git a/docs/root/source/installation/api/http-samples/get-block-txid-request.http b/docs/root/source/installation/api/http-samples/get-block-txid-request.http
index 7ecb018..b3e8bd3 100644
--- a/docs/root/source/installation/api/http-samples/get-block-txid-request.http
+++ b/docs/root/source/installation/api/http-samples/get-block-txid-request.http
@@ -1,3 +1,3 @@
-GET /api/v1/blocks?transaction_id=6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2 HTTP/1.1
+GET /api/v1/blocks?transaction_id=61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac HTTP/1.1
 Host: example.com
 
diff --git a/docs/root/source/installation/api/http-samples/get-tx-by-asset-request.http b/docs/root/source/installation/api/http-samples/get-tx-by-asset-request.http
index fb15c84..560bcbc 100644
--- a/docs/root/source/installation/api/http-samples/get-tx-by-asset-request.http
+++ b/docs/root/source/installation/api/http-samples/get-tx-by-asset-request.http
@@ -1,3 +1,3 @@
-GET /api/v1/transactions?operation=TRANSFER&asset_id=6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2 HTTP/1.1
+GET /api/v1/transactions?operation=TRANSFER&asset_id=61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac HTTP/1.1
 Host: example.com
 
diff --git a/docs/root/source/installation/api/http-samples/get-tx-by-asset-response.http b/docs/root/source/installation/api/http-samples/get-tx-by-asset-response.http
index 6ed97dc..32d5554 100644
--- a/docs/root/source/installation/api/http-samples/get-tx-by-asset-response.http
+++ b/docs/root/source/installation/api/http-samples/get-tx-by-asset-response.http
@@ -2,16 +2,18 @@ HTTP/1.1 200 OK
 Content-Type: application/json
 
 [{
-  "asset": {
-    "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2"
-  },
-  "id": "2bf8ae1e3bc889a26df129dd6bbe6ccab30d1ae8e9e434fae1c4446042a68931",
+  "assets": [
+    {
+      "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac"
+    }
+  ],
+  "id": "b6e1ab3d48bbbbb0e40b952e70ec5d439b2745e0ba0c44b4ee877657e9ac33f0",
   "inputs": [
     {
-      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUA90mMa9AWnbI70CUSVgzV9kRFf3tQ20RUIczNFqmwg9xrpOk_5uNoJB4bWRIojZmUhEyxSueCHLpqPXCEuyisE",
+      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUA4BB4fxDXK3CQTbKpH5gTAN76NG-iopNuuDEfBbZ1Fl-ipNU46t8VCvK9ghm9Q53aFRW6DDiW5wcWXxY0sS4EJ",
       "fulfills": {
         "output_index": 0,
-        "transaction_id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2"
+        "transaction_id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac"
       },
       "owners_before": [
         "4K9sWUMFwTgaDGPfdynrbxWqWS6sWmKbZoTjxLtVUibD"
@@ -40,16 +42,18 @@ Content-Type: application/json
   "version": "2.0"
 },
 {
-  "asset": {
-    "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2"
-  },
-  "id": "b9b614175eaed7cc93d9b80ebc2a91d35ae31928a7c218ae982272bb1785ef16",
+  "assets": [
+    {
+      "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac"
+    }
+  ],
+  "id": "e43d3f93d90d22ef11c21607e3415bfcda4e0c7dd60412fbb55daf32978a3126",
   "inputs": [
     {
-      "fulfillment": "pGSAICw7Ul-c2lG6NFbHp3FbKRC7fivQcNGO7GS4wV3A-1QggUDi2bAVKJgEyE3LzMrAnAu1PnNs9DbDNkABaY6j3OCNEVwNVNg3V3qELOFNnH8vGUevREr4E-8Vb1Kzk4VR71MO",
+      "fulfillment": "pGSAICw7Ul-c2lG6NFbHp3FbKRC7fivQcNGO7GS4wV3A-1QggUBjj_XTjB3yJdG8JMNKnkkHvcX_BTOkl-YacRD4yKqxUCeL-VTgbrLgi5a3gGxNJcTkZP1gF0nsby8cgV4xmOcB",
       "fulfills": {
         "output_index": 0,
-        "transaction_id": "2bf8ae1e3bc889a26df129dd6bbe6ccab30d1ae8e9e434fae1c4446042a68931"
+        "transaction_id": "b6e1ab3d48bbbbb0e40b952e70ec5d439b2745e0ba0c44b4ee877657e9ac33f0"
       },
       "owners_before": [
         "3yfQPHeWAa1MxTX9Zf9176QqcpcnWcanVZZbaHb8B3h9"
diff --git a/docs/root/source/installation/api/http-samples/get-tx-id-request.http b/docs/root/source/installation/api/http-samples/get-tx-id-request.http
index c6c834c..1574cdd 100644
--- a/docs/root/source/installation/api/http-samples/get-tx-id-request.http
+++ b/docs/root/source/installation/api/http-samples/get-tx-id-request.http
@@ -1,3 +1,3 @@
-GET /api/v1/transactions/6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2 HTTP/1.1
+GET /api/v1/transactions/61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac HTTP/1.1
 Host: example.com
 
diff --git a/docs/root/source/installation/api/http-samples/get-tx-id-response.http b/docs/root/source/installation/api/http-samples/get-tx-id-response.http
index c5f3b71..0ee9bb2 100644
--- a/docs/root/source/installation/api/http-samples/get-tx-id-response.http
+++ b/docs/root/source/installation/api/http-samples/get-tx-id-response.http
@@ -2,15 +2,17 @@ HTTP/1.1 200 OK
 Content-Type: application/json
 
 {
-  "asset": {
-    "data": {
-      "msg": "Hello Planetmint!"
+  "assets": [
+    {
+      "data": {
+        "msg": "Hello Planetmint!"
+      }
     }
-  },
-  "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2",
+  ],
+  "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac",
   "inputs": [
     {
-      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUBcdRj6EnG3MPl47m3XPd1HNfe7q3WL4T6MewNNnat33UvzVnPHo_vossv57M7L064VwrYMLGp097H7IeHpDngK",
+      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUCWcUaLa2U-nkmZ6oYj14aeV6B4TJH2NvZ8k2ZTwcGiaiCGXDQT2dEPfMCFwM8lwSousafCu4c7EgVZ1GzUDjsN",
       "fulfills": null,
       "owners_before": [
         "4K9sWUMFwTgaDGPfdynrbxWqWS6sWmKbZoTjxLtVUibD"
diff --git a/docs/root/source/installation/api/http-samples/index-response.http b/docs/root/source/installation/api/http-samples/index-response.http
index c593a91..f7e524e 100644
--- a/docs/root/source/installation/api/http-samples/index-response.http
+++ b/docs/root/source/installation/api/http-samples/index-response.http
@@ -6,7 +6,7 @@ Content-Type: application/json
     "v1": {
       "assets": "/api/v1/assets/",
       "blocks": "/api/v1/blocks/",
-      "docs": "https://docs.planetmint.com/projects/server/en/v0.9.0/http-client-server-api.html",
+      "docs": "https://docs.planetmint.com/projects/server/en/v0.9.1/http-client-server-api.html",
       "metadata": "/api/v1/metadata/",
       "outputs": "/api/v1/outputs/",
       "streams": "ws://localhost:9985/api/v1/streams/valid_transactions",
@@ -14,7 +14,7 @@ Content-Type: application/json
       "validators": "/api/v1/validators"
     }
   },
-  "docs": "https://docs.planetmint.com/projects/server/en/v0.9.0/",
+  "docs": "https://docs.planetmint.com/projects/server/en/v0.9.1/",
   "software": "Planetmint",
-  "version": "0.9.0"
+  "version": "0.9.1"
 }
diff --git a/docs/root/source/installation/api/http-samples/post-tx-request.http b/docs/root/source/installation/api/http-samples/post-tx-request.http
index 8ab0710..a2bca94 100644
--- a/docs/root/source/installation/api/http-samples/post-tx-request.http
+++ b/docs/root/source/installation/api/http-samples/post-tx-request.http
@@ -3,15 +3,17 @@ Host: example.com
 Content-Type: application/json
 
 {
-  "asset": {
-    "data": {
-      "msg": "Hello Planetmint!"
+  "assets": [
+    {
+      "data": {
+        "msg": "Hello Planetmint!"
+      }
     }
-  },
-  "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2",
+  ],
+  "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac",
   "inputs": [
     {
-      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUBcdRj6EnG3MPl47m3XPd1HNfe7q3WL4T6MewNNnat33UvzVnPHo_vossv57M7L064VwrYMLGp097H7IeHpDngK",
+      "fulfillment": "pGSAIDE5i63cn4X8T8N1sZ2mGkJD5lNRnBM4PZgI_zvzbr-cgUCWcUaLa2U-nkmZ6oYj14aeV6B4TJH2NvZ8k2ZTwcGiaiCGXDQT2dEPfMCFwM8lwSousafCu4c7EgVZ1GzUDjsN",
       "fulfills": null,
       "owners_before": [
         "4K9sWUMFwTgaDGPfdynrbxWqWS6sWmKbZoTjxLtVUibD"
diff --git a/docs/root/source/installation/api/http-samples/post-tx-response.http b/docs/root/source/installation/api/http-samples/post-tx-response.http
index 653014e..eabf577 100644
--- a/docs/root/source/installation/api/http-samples/post-tx-response.http
+++ b/docs/root/source/installation/api/http-samples/post-tx-response.http
@@ -2,15 +2,17 @@ HTTP/1.1 202 Accepted
 Content-Type: application/json
 
 {
-  "asset": {
-    "data": {
-      "msg": "Hello Planetmint!"
+  "assets": [
+    {
+      "data": {
+        "msg": "Hello Planetmint!"
+      }
     }
-  },
-  "id": "6438c733f53dff60bdeded80e8c95126dd3a7ce8c1ee5d5591d030e61cde35d2",
+  ],
+  "id": "61e1312b80705e0dabb948c9d78dae7f62d64832abda822b13d89c4a7305d4ac",
   "inputs": [
     {
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