P2P message format

This page details the structure and layout of messages used by the Tezos P2P layer.

The elementary types used for message or header fields are documented in the Data_encoding module, for example:

• unsigned 8-bit integer

• unsigned 16-bit integer

• signed 32-bit integer

• signed 64-bit integer

Additionally, the type unsigned 30-bit integer is used to denote the subset of positive integers of type signed 31-bit integers.

Note

31-bit integers: The internal representation of integers in OCaml reserves one bit for GC tagging. The remaining bits encode a signed integer. For compatibility with 32-bit machines, we restrict these native integers to the 31-bit range.

Block header (shell)

Name	Size	Contents
level	4 bytes	signed 32-bit integer
proto	1 byte	unsigned 8-bit integer
predecessor	32 bytes	bytes
timestamp	8 bytes	signed 64-bit integer
validation_pass	1 byte	unsigned 8-bit integer
operations_hash	32 bytes	bytes
# bytes in field “fitness”	4 bytes	unsigned 30-bit integer
fitness	Variable	sequence of $fitness.elem
context	32 bytes	bytes
protocol_data	Variable	bytes

fitness.elem

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	bytes

Operation (shell)

Name	Size	Contents
branch	32 bytes	bytes
data	Variable	bytes

Block_header (alpha-specific)

Name	Size	Contents
payload_hash	32 bytes	bytes
payload_round	4 bytes	signed 32-bit integer
proof_of_work_nonce	8 bytes	bytes
? presence of field “seed_nonce_hash”	1 byte	boolean (0 for false, 255 for true)
seed_nonce_hash	32 bytes	bytes
liquidity_baking_toggle_vote	1 byte	signed 8-bit integer
signature	64 bytes	bytes

Operation (alpha-specific)

Name	Size	Contents
contents	Variable	sequence of $alpha.operation.alpha.contents
signature	64 bytes	bytes

public_key_hash (21 bytes, 8-bit tag)

Ed25519 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Ed25519.Public_key_hash	20 bytes	bytes

Secp256k1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Secp256k1.Public_key_hash	20 bytes	bytes

P256 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
P256.Public_key_hash	20 bytes	bytes

N.t

A variable-length sequence of bytes encoding a Zarith natural number. Each byte has a running unary size bit: the most significant bit of each byte indicates whether this is the last byte in the sequence (0) or whether the sequence continues (1). Size bits ignored, the data is the binary representation of the number in little-endian order.

Name	Size	Contents
N.t	Determined from data	bytes

X_0

Name	Size	Contents
level	4 bytes	signed 32-bit integer
index	1 byte	unsigned 8-bit integer
header	48 bytes	bytes

X_1

Name	Size	Contents
alice	21 bytes	$public_key_hash
bob	21 bytes	$public_key_hash

X_5 (33 bytes, 8-bit tag) *********************

Value (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
value	32 bytes	bytes

Node (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
node	32 bytes	bytes

X_8

Name	Size	Contents
# bytes in next field	1 byte	unsigned 8-bit integer
Unnamed field 0	Variable	bytes

X_9

Name	Size	Contents
length	8 bytes	signed 64-bit integer
segment	Determined from data	$X_8
proof	Determined from data	$inode_tree

X_12

Name	Size	Contents
Unnamed field 0	1 byte	unsigned 8-bit integer
Unnamed field 1	Determined from data	$inode_tree

X_13 (Determined from data, 8-bit tag)

sparse_proof (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
sparse_proof	Variable	sequence of $X_12

dense_proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
dense_proof	Determined from data	sequence of exactly 32 $inode_tree

X_11

Name	Size	Contents
length	8 bytes	signed 64-bit integer
proofs	Determined from data	$X_13

X_14

Name	Size	Contents
Unnamed field 0	Determined from data	$X_8
Unnamed field 1	Determined from data	$tree_encoding

inode_tree (Determined from data, 8-bit tag)

Blinded_inode (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
blinded_inode	32 bytes	bytes

Inode_values (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
inode_values	Variable	sequence of $X_14

Inode_tree (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
inode_tree	Determined from data	$X_11

Inode_extender (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
inode_extender	Determined from data	$X_9

None (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

tree_encoding (Determined from data, 8-bit tag)

Value (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
value	Variable	bytes

Blinded_value (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
blinded_value	32 bytes	bytes

Node (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
node	Variable	sequence of $X_14

Blinded_node (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
blinded_node	32 bytes	bytes

Inode (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
inode	Determined from data	$X_11

Extender (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
extender	Determined from data	$X_9

None (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

X_4

Name	Size	Contents
version	2 bytes	signed 16-bit integer
before	33 bytes	$X_5
after	33 bytes	$X_5
state	Determined from data	$tree_encoding

X_39

Name	Size	Contents
inbox_level	4 bytes	signed 32-bit integer
message_counter	Determined from data	$N.t
# bytes in next field	4 bytes	unsigned 30-bit integer
payload	Variable	bytes

X_40 (Determined from data, 8-bit tag)

No_input_required (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

Initial (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

First_after (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
level	4 bytes	signed 32-bit integer
counter	Determined from data	$N.t

X_3

Name	Size	Contents
tree_proof	Determined from data	$X_4
? presence of field “given”	1 byte	boolean (0 for false, 255 for true)
given	Determined from data	$X_39
requested	Determined from data	$X_40

X_79 (Determined from data, 8-bit tag)

Arithmetic PVM with proof (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
proof	Determined from data	$X_3

Wasm 2.0.0 PVM with proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
proof	Determined from data	$X_3

Unencodable (tag 255)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

X_80

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	bytes

X_81

Name	Size	Contents
? presence of field “state”	1 byte	boolean (0 for false, 255 for true)
state	32 bytes	bytes
tick	Determined from data	$N.t

X_82 (Determined from data, 8-bit tag)

Dissection (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	sequence of $X_81

Proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
pvm_step	Determined from data	$X_79
? presence of field “inbox”	1 byte	boolean (0 for false, 255 for true)
inbox	Determined from data	$X_80

X_2

Name	Size	Contents
choice	Determined from data	$N.t
step	Determined from data	$X_82

X_83

Name	Size	Contents
compressed_state	32 bytes	bytes
inbox_level	4 bytes	signed 32-bit integer
predecessor	32 bytes	bytes
number_of_ticks	4 bytes	signed 32-bit integer

X_84

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	bytes

X_85 (Enumeration: unsigned 8-bit integer):

Case number	Encoded string
0	arith_pvm_kind
1	wasm_2_0_0_pvm_kind

alpha.contract_id (22 bytes, 8-bit tag)

Implicit (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Signature.Public_key_hash	21 bytes	$public_key_hash

Originated (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Contract_hash	20 bytes	bytes
padding	1 byte	padding

X_164 (Determined from data, 8-bit tag)

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer

case 2 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer

case 3 (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer

X_163

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
contents	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
ty	Variable	bytes
ticketer	22 bytes	$alpha.contract_id
amount	Determined from data	$X_164
claimer	21 bytes	$public_key_hash

X_165

Name	Size	Contents
sender	21 bytes	$public_key_hash
destination	20 bytes	bytes
ticket_hash	32 bytes	bytes
amount	Determined from data	$X_164

X_167 (Determined from data, 8-bit tag)

Batch (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
batch	Variable	bytes

Deposit (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
deposit	Determined from data	$X_165

X_168

Name	Size	Contents
context_hash	32 bytes	bytes
withdraw_list_hash	32 bytes	bytes

X_176 (33 bytes, 8-bit tag) ***********************

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Context_hash	32 bytes	bytes

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Context_hash	32 bytes	bytes

X_174

Name	Size	Contents
Unnamed field 0	Determined from data	$X_8
Unnamed field 1	33 bytes	$X_176

X_183

Name	Size	Contents
Unnamed field 0	32 bytes	bytes
Unnamed field 1	32 bytes	bytes

X_187

Name	Size	Contents
Unnamed field 0	32 bytes	bytes

X_195

This value’s binary representation is empty. It takes zero (0) bytes of output. X_199 (Determined from data, 8-bit tag) ***********************************

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer

case 2 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer

case 3 (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer

case 4 (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer
Unnamed field 1	32 bytes	$X_187

case 5 (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer
Unnamed field 1	32 bytes	$X_187

case 6 (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer
Unnamed field 1	32 bytes	$X_187

case 7 (tag 7)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer
Unnamed field 1	32 bytes	$X_187

case 8 (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer
Unnamed field 1	32 bytes	$X_187

case 9 (tag 9)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer
Unnamed field 1	32 bytes	$X_187

case 10 (tag 10)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer
Unnamed field 1	32 bytes	$X_187

case 11 (tag 11)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer
Unnamed field 1	32 bytes	$X_187

case 12 (tag 12)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer
Unnamed field 1	64 bytes	$X_183

case 13 (tag 13)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer
Unnamed field 1	64 bytes	$X_183

case 14 (tag 14)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer
Unnamed field 1	64 bytes	$X_183

case 15 (tag 15)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer
Unnamed field 1	64 bytes	$X_183

case 128 (tag 128)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 129 (tag 129)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	Variable	sequence of exactly 1 $X_174

case 130 (tag 130)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	Variable	sequence of exactly 2 $X_174

case 131 (tag 131)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	sequence of $X_174

case 192 (tag 192)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	1 byte	unsigned 8-bit integer
Unnamed field 0	Variable	bytes

case 193 (tag 193)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	2 bytes	unsigned 16-bit integer
Unnamed field 0	Variable	bytes

case 195 (tag 195)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	bytes

case 224 (tag 224)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	1 byte	unsigned 8-bit integer
Unnamed field 1	Determined from data	$X_8
Unnamed field 2	32 bytes	bytes

case 225 (tag 225)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	unsigned 16-bit integer
Unnamed field 1	Determined from data	$X_8
Unnamed field 2	32 bytes	bytes

case 226 (tag 226)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	4 bytes	signed 32-bit integer
Unnamed field 1	Determined from data	$X_8
Unnamed field 2	32 bytes	bytes

case 227 (tag 227)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	8 bytes	signed 64-bit integer
Unnamed field 1	Determined from data	$X_8
Unnamed field 2	32 bytes	bytes

X_169

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
Unnamed field 0	Variable	sequence of $X_199

X_293 (Determined from data, 8-bit tag)

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	signed 16-bit integer
Unnamed field 1	32 bytes	bytes
Unnamed field 2	32 bytes	bytes
Unnamed field 3	Determined from data	$X_169

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	signed 16-bit integer
Unnamed field 1	32 bytes	bytes
Unnamed field 2	32 bytes	bytes
Unnamed field 3	Determined from data	$X_169

case 2 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	signed 16-bit integer
Unnamed field 1	32 bytes	bytes
Unnamed field 2	32 bytes	bytes
Unnamed field 3	Determined from data	$X_169

case 3 (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Unnamed field 0	2 bytes	signed 16-bit integer
Unnamed field 1	32 bytes	bytes
Unnamed field 2	32 bytes	bytes
Unnamed field 3	Determined from data	$X_169

X_295 (Determined from data, 8-bit tag)

None (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

Some (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Commitment_hash	32 bytes	bytes

X_294

Name	Size	Contents
level	4 bytes	signed 32-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
messages	Variable	sequence of bytes
predecessor	Determined from data	$X_295
inbox_merkle_root	32 bytes	bytes

Z.t

A variable-length sequence of bytes encoding a Zarith integer. Each byte has a running unary size bit: the most significant bit of each byte indicates whether this is the last byte in the sequence (0) or whether the sequence continues (1). The second most significant bit of the first byte is reserved for the sign (0 for positive, 1 for negative). Size and sign bits ignored, the data is the binary representation of the absolute value of the number in little-endian order.

Name	Size	Contents
Z.t	Determined from data	bytes

alpha.contract_id.originated (22 bytes, 8-bit tag)

Originated (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Contract_hash	20 bytes	bytes
padding	1 byte	padding

alpha.scripted.contracts

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
code	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
storage	Variable	bytes

alpha.entrypoint (Determined from data, 8-bit tag)

default (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

root (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

do (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

set_delegate (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

remove_delegate (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

named (tag 255)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	1 byte	unsigned 8-bit integer
Unnamed field 0	Variable	bytes

X_296

Name	Size	Contents
entrypoint	Determined from data	$alpha.entrypoint
# bytes in next field	4 bytes	unsigned 30-bit integer
value	Variable	bytes

public_key (Determined from data, 8-bit tag)

Ed25519 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Ed25519.Public_key	32 bytes	bytes

Secp256k1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Secp256k1.Public_key	33 bytes	bytes

P256 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
P256.Public_key	33 bytes	bytes

X_297

Name	Size	Contents
Unnamed field 0	100 bytes	bytes
Unnamed field 1	100 bytes	bytes

alpha.inlined.preendorsement.contents (43 bytes, 8-bit tag)

Preendorsement (tag 20)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
slot	2 bytes	unsigned 16-bit integer
level	4 bytes	signed 32-bit integer
round	4 bytes	signed 32-bit integer
block_payload_hash	32 bytes	bytes

alpha.inlined.preendorsement

Name	Size	Contents
branch	32 bytes	bytes
operations	43 bytes	$alpha.inlined.preendorsement.contents
signature	Variable	bytes

alpha.block_header.alpha.full_header

Name	Size	Contents
level	4 bytes	signed 32-bit integer
proto	1 byte	unsigned 8-bit integer
predecessor	32 bytes	bytes
timestamp	8 bytes	signed 64-bit integer
validation_pass	1 byte	unsigned 8-bit integer
operations_hash	32 bytes	bytes
# bytes in field “fitness”	4 bytes	unsigned 30-bit integer
fitness	Variable	sequence of $X_80
context	32 bytes	bytes
payload_hash	32 bytes	bytes
payload_round	4 bytes	signed 32-bit integer
proof_of_work_nonce	8 bytes	bytes
? presence of field “seed_nonce_hash”	1 byte	boolean (0 for false, 255 for true)
seed_nonce_hash	32 bytes	bytes
liquidity_baking_toggle_vote	1 byte	signed 8-bit integer
signature	64 bytes	bytes

alpha.inlined.endorsement_mempool.contents (43 bytes, 8-bit tag)

Endorsement (tag 21)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
slot	2 bytes	unsigned 16-bit integer
level	4 bytes	signed 32-bit integer
round	4 bytes	signed 32-bit integer
block_payload_hash	32 bytes	bytes

alpha.inlined.endorsement

Name	Size	Contents
branch	32 bytes	bytes
operations	43 bytes	$alpha.inlined.endorsement_mempool.contents
signature	Variable	bytes

alpha.operation.alpha.contents (Determined from data, 8-bit tag)

Seed_nonce_revelation (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
level	4 bytes	signed 32-bit integer
nonce	32 bytes	bytes

Double_endorsement_evidence (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
op1	Variable	$alpha.inlined.endorsement
# bytes in next field	4 bytes	unsigned 30-bit integer
op2	Variable	$alpha.inlined.endorsement

Double_baking_evidence (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
bh1	Determined from data	$alpha.block_header.alpha.full_header
# bytes in next field	4 bytes	unsigned 30-bit integer
bh2	Determined from data	$alpha.block_header.alpha.full_header

Activate_account (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
pkh	20 bytes	bytes
secret	20 bytes	bytes

Proposals (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
period	4 bytes	signed 32-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
proposals	Variable	sequence of bytes

Ballot (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
period	4 bytes	signed 32-bit integer
proposal	32 bytes	bytes
ballot	1 byte	signed 8-bit integer

Double_preendorsement_evidence (tag 7)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
op1	Variable	$alpha.inlined.preendorsement
# bytes in next field	4 bytes	unsigned 30-bit integer
op2	Variable	$alpha.inlined.preendorsement

Vdf_revelation (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
solution	200 bytes	$X_297

Failing_noop (tag 17)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
arbitrary	Variable	bytes

Preendorsement (tag 20)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
slot	2 bytes	unsigned 16-bit integer
level	4 bytes	signed 32-bit integer
round	4 bytes	signed 32-bit integer
block_payload_hash	32 bytes	bytes

Endorsement (tag 21)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
slot	2 bytes	unsigned 16-bit integer
level	4 bytes	signed 32-bit integer
round	4 bytes	signed 32-bit integer
block_payload_hash	32 bytes	bytes

Dal_slot_availability (tag 22)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
endorser	21 bytes	$public_key_hash
endorsement	Determined from data	$Z.t

Reveal (tag 107)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
public_key	Determined from data	$public_key

Transaction (tag 108)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
amount	Determined from data	$N.t
destination	22 bytes	$alpha.contract_id
? presence of field “parameters”	1 byte	boolean (0 for false, 255 for true)
parameters	Determined from data	$X_296

Origination (tag 109)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
balance	Determined from data	$N.t
? presence of field “delegate”	1 byte	boolean (0 for false, 255 for true)
delegate	21 bytes	$public_key_hash
script	Determined from data	$alpha.scripted.contracts

Delegation (tag 110)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
? presence of field “delegate”	1 byte	boolean (0 for false, 255 for true)
delegate	21 bytes	$public_key_hash

Register_global_constant (tag 111)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in next field	4 bytes	unsigned 30-bit integer
value	Variable	bytes

Set_deposits_limit (tag 112)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
? presence of field “limit”	1 byte	boolean (0 for false, 255 for true)
limit	Determined from data	$N.t

Increase_paid_storage (tag 113)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
amount	Determined from data	$Z.t
destination	22 bytes	$alpha.contract_id.originated

Tx_rollup_origination (tag 150)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t

Tx_rollup_submit_batch (tag 151)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
content	Variable	bytes
? presence of field “burn_limit”	1 byte	boolean (0 for false, 255 for true)
burn_limit	Determined from data	$N.t

Tx_rollup_commit (tag 152)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes
commitment	Determined from data	$X_294

Tx_rollup_return_bond (tag 153)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes

Tx_rollup_finalize_commitment (tag 154)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes

Tx_rollup_remove_commitment (tag 155)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes

Tx_rollup_rejection (tag 156)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes
level	4 bytes	signed 32-bit integer
message	Determined from data	$X_167
message_position	Determined from data	$N.t
# bytes in next field	4 bytes	unsigned 30-bit integer
message_path	Variable	sequence of bytes
message_result_hash	32 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
message_result_path	Variable	sequence of bytes
previous_message_result	64 bytes	$X_168
# bytes in next field	4 bytes	unsigned 30-bit integer
previous_message_result_path	Variable	sequence of bytes
proof	Determined from data	$X_293

Tx_rollup_dispatch_tickets (tag 157)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
tx_rollup	20 bytes	bytes
level	4 bytes	signed 32-bit integer
context_hash	32 bytes	bytes
message_index	4 bytes	signed 31-bit integer in the range -1073741824 to 1073741823
# bytes in next field	4 bytes	unsigned 30-bit integer
message_result_path	Variable	sequence of bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
tickets_info	Variable	sequence of $X_163

Transfer_ticket (tag 158)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in next field	4 bytes	unsigned 30-bit integer
ticket_contents	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
ticket_ty	Variable	bytes
ticket_ticketer	22 bytes	$alpha.contract_id
ticket_amount	Determined from data	$N.t
destination	22 bytes	$alpha.contract_id
# bytes in next field	4 bytes	unsigned 30-bit integer
entrypoint	Variable	bytes

Sc_rollup_originate (tag 200)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
kind	1 byte	unsigned 8-bit integer encoding an enumeration (see X_85)
# bytes in next field	4 bytes	unsigned 30-bit integer
boot_sector	Variable	bytes
origination_proof	Determined from data	$X_79
# bytes in next field	4 bytes	unsigned 30-bit integer
parameters_ty	Variable	bytes

Sc_rollup_add_messages (tag 201)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
message	Variable	sequence of $X_84

Sc_rollup_cement (tag 202)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
commitment	32 bytes	bytes

Sc_rollup_publish (tag 203)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
commitment	72 bytes	$X_83

Sc_rollup_refute (tag 204)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
opponent	21 bytes	$public_key_hash
? presence of field “refutation”	1 byte	boolean (0 for false, 255 for true)
refutation	Determined from data	$X_2

Sc_rollup_timeout (tag 205)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
stakers	42 bytes	$X_1

Sc_rollup_execute_outbox_message (tag 206)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
cemented_commitment	32 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
output_proof	Variable	bytes

Sc_rollup_recover_bond (tag 207)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
rollup	20 bytes	bytes

Sc_rollup_dal_slot_subscribe (tag 208)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
# bytes in field “alpha.rollup_address”	4 bytes	unsigned 30-bit integer
rollup	Variable	bytes
slot_index	1 byte	unsigned 8-bit integer

Dal_publish_slot_header (tag 230)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
source	21 bytes	$public_key_hash
fee	Determined from data	$N.t
counter	Determined from data	$N.t
gas_limit	Determined from data	$N.t
storage_limit	Determined from data	$N.t
slot	53 bytes	$X_0