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
per_block_votes	1 byte	$alpha.per_block_votes
signature	Variable	bytes

alpha.per_block_votes (1 byte, 8-bit tag)

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 2 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 4 (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 5 (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 6 (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 8 (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 9 (tag 9)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 10 (tag 10)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

Operation (alpha-specific)

Name	Size	Contents
contents_and_signature_prefix	Variable	sequence of $alpha.operation.alpha.contents_or_signature_prefix
signature_suffix	64 bytes	bytes

bls_signature_prefix (33 bytes, 8-bit tag)

Bls_prefix (tag 3)

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

Bls (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Bls12_381.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_2

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

X_3

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
new_state	Variable	sequence of bytes
fee	32 bytes	bytes
exit_validity	1 byte	boolean (0 for false, 255 for true)

X_1

Name	Size	Contents
Unnamed field 0	Determined from data	$X_2
Unnamed field 1	Determined from data	$X_3

X_6

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
new_state	Variable	sequence of bytes
fee	32 bytes	bytes

X_4

Name	Size	Contents
Unnamed field 0	Determined from data	$X_2
Unnamed field 1	Determined from data	$X_6

X_7

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

X_0

Name	Size	Contents
# bytes in next field	4 bytes	unsigned 30-bit integer
pending_pis	Variable	sequence of $X_1
# bytes in next field	4 bytes	unsigned 30-bit integer
private_pis	Variable	sequence of $X_4
fee_pi	Determined from data	$X_7
# bytes in next field	4 bytes	unsigned 30-bit integer
proof	Variable	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

X_10

Name	Size	Contents
id	32 bytes	bytes
amount	Determined from data	$Z.t

X_9

Name	Size	Contents
op_code	4 bytes	signed 31-bit integer in the range -1073741824 to 1073741823
price	Determined from data	$X_10
l1_dst	21 bytes	$public_key_hash
rollup_id	20 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
payload	Variable	sequence of bytes

alpha.michelson.v1.primitives (Enumeration: unsigned 8-bit integer):

Case number	Encoded string
0	parameter
1	storage
2	code
3	False
4	Elt
5	Left
6	None
7	Pair
8	Right
9	Some
10	True
11	Unit
12	PACK
13	UNPACK
14	BLAKE2B
15	SHA256
16	SHA512
17	ABS
18	ADD
19	AMOUNT
20	AND
21	BALANCE
22	CAR
23	CDR
24	CHECK_SIGNATURE
25	COMPARE
26	CONCAT
27	CONS
28	CREATE_ACCOUNT
29	CREATE_CONTRACT
30	IMPLICIT_ACCOUNT
31	DIP
32	DROP
33	DUP
34	EDIV
35	EMPTY_MAP
36	EMPTY_SET
37	EQ
38	EXEC
39	FAILWITH
40	GE
41	GET
42	GT
43	HASH_KEY
44	IF
45	IF_CONS
46	IF_LEFT
47	IF_NONE
48	INT
49	LAMBDA
50	LE
51	LEFT
52	LOOP
53	LSL
54	LSR
55	LT
56	MAP
57	MEM
58	MUL
59	NEG
60	NEQ
61	NIL
62	NONE
63	NOT
64	NOW
65	OR
66	PAIR
67	PUSH
68	RIGHT
69	SIZE
70	SOME
71	SOURCE
72	SENDER
73	SELF
74	STEPS_TO_QUOTA
75	SUB
76	SWAP
77	TRANSFER_TOKENS
78	SET_DELEGATE
79	UNIT
80	UPDATE
81	XOR
82	ITER
83	LOOP_LEFT
84	ADDRESS
85	CONTRACT
86	ISNAT
87	CAST
88	RENAME
89	bool
90	contract
91	int
92	key
93	key_hash
94	lambda
95	list
96	map
97	big_map
98	nat
99	option
100	or
101	pair
102	set
103	signature
104	string
105	bytes
106	mutez
107	timestamp
108	unit
109	operation
110	address
111	SLICE
112	DIG
113	DUG
114	EMPTY_BIG_MAP
115	APPLY
116	chain_id
117	CHAIN_ID
118	LEVEL
119	SELF_ADDRESS
120	never
121	NEVER
122	UNPAIR
123	VOTING_POWER
124	TOTAL_VOTING_POWER
125	KECCAK
126	SHA3
127	PAIRING_CHECK
128	bls12_381_g1
129	bls12_381_g2
130	bls12_381_fr
131	sapling_state
132	sapling_transaction_deprecated
133	SAPLING_EMPTY_STATE
134	SAPLING_VERIFY_UPDATE
135	ticket
136	TICKET_DEPRECATED
137	READ_TICKET
138	SPLIT_TICKET
139	JOIN_TICKETS
140	GET_AND_UPDATE
141	chest
142	chest_key
143	OPEN_CHEST
144	VIEW
145	view
146	constant
147	SUB_MUTEZ
148	tx_rollup_l2_address
149	MIN_BLOCK_TIME
150	sapling_transaction
151	EMIT
152	Lambda_rec
153	LAMBDA_REC
154	TICKET
155	BYTES
156	NAT

micheline.alpha.michelson_v1.expression (Determined from data, 8-bit tag)

Int (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
int	Determined from data	$Z.t

String (tag 1)

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

Sequence (tag 2)

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 $micheline.alpha.michelson_v1.expression

Prim__no_args__no_annots (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)

Prim__no_args__some_annots (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
# bytes in next field	4 bytes	unsigned 30-bit integer
annots	Variable	bytes

Prim__1_arg__no_annots (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
arg	Determined from data	$micheline.alpha.michelson_v1.expression

Prim__1_arg__some_annots (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
arg	Determined from data	$micheline.alpha.michelson_v1.expression
# bytes in next field	4 bytes	unsigned 30-bit integer
annots	Variable	bytes

Prim__2_args__no_annots (tag 7)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
arg1	Determined from data	$micheline.alpha.michelson_v1.expression
arg2	Determined from data	$micheline.alpha.michelson_v1.expression

Prim__2_args__some_annots (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
arg1	Determined from data	$micheline.alpha.michelson_v1.expression
arg2	Determined from data	$micheline.alpha.michelson_v1.expression
# bytes in next field	4 bytes	unsigned 30-bit integer
annots	Variable	bytes

Prim__generic (tag 9)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
prim	1 byte	unsigned 8-bit integer encoding an enumeration (see alpha.michelson.v1.primitives)
# bytes in next field	4 bytes	unsigned 30-bit integer
args	Variable	sequence of $micheline.alpha.michelson_v1.expression
# bytes in next field	4 bytes	unsigned 30-bit integer
annots	Variable	bytes

Bytes (tag 10)

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

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_13 (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
contents	Determined from data	$micheline.alpha.michelson_v1.expression
ty	Determined from data	$micheline.alpha.michelson_v1.expression
ticketer	22 bytes	$alpha.contract_id

X_8

Name	Size	Contents
Unnamed field 0	Determined from data	$X_9
Unnamed field 1	Determined from data	$X_13

X_16 (1 byte, 8-bit tag) ********************

Public (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

Private (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

Fee (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

X_14

Name	Size	Contents
Unnamed field 0	Determined from data	$X_2
Unnamed field 1	1 byte	$X_16

X_17

Name	Size	Contents
slot_index	1 byte	unsigned 8-bit integer
commitment	48 bytes	bytes
commitment_proof	48 bytes	bytes

X_18

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

X_19

Name	Size	Contents
published_level	4 bytes	signed 32-bit integer
slot_index	1 byte	unsigned 8-bit integer
page_index	2 bytes	signed 16-bit integer

X_20 (Determined from data, 8-bit tag)

raw data proof (tag 0)

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

metadata proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

dal page proof (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
dal_page_id	7 bytes	$X_19
# bytes in next field	4 bytes	unsigned 30-bit integer
dal_proof	Variable	bytes

X_21 (Determined from data, 8-bit tag)

inbox proof (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
level	4 bytes	signed 32-bit integer
message_counter	Determined from data	$N.t
# bytes in next field	4 bytes	unsigned 30-bit integer
serialized_proof	Variable	bytes

reveal proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
reveal_proof	Determined from data	$X_20

first input (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

X_22

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_23 (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_22

Proof (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
# bytes in next field	4 bytes	unsigned 30-bit integer
pvm_step	Variable	bytes
? presence of field “input_proof”	1 byte	boolean (0 for false, 255 for true)
input_proof	Determined from data	$X_21

X_24 (Determined from data, 8-bit tag)

Start (tag 0)

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

Move (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
choice	Determined from data	$N.t
step	Determined from data	$X_23

X_25

Name	Size	Contents
compressed_state	32 bytes	bytes
inbox_level	4 bytes	signed 32-bit integer
predecessor	32 bytes	bytes
number_of_ticks	8 bytes	signed 64-bit integer

X_27 (Enumeration: unsigned 8-bit integer):

Case number	Encoded string
0	arith
1	wasm_2_0_0

X_28

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

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

Bls (tag 3)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
Bls12_381.Public_key	48 bytes	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

deposit (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

stake (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

unstake (tag 7)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

finalize_unstake (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

set_delegate_parameters (tag 9)

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_29

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

X_30

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

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

Preattestation (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.preattestation

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

fitness.elem

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

alpha.per_block_votes (1 byte, 8-bit tag)

case 0 (tag 0)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 1 (tag 1)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 2 (tag 2)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 4 (tag 4)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 5 (tag 5)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 6 (tag 6)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 8 (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 9 (tag 9)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

case 10 (tag 10)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer

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 $fitness.elem
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
per_block_votes	1 byte	$alpha.per_block_votes
signature	Variable	bytes

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

Attestation (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.attestation

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

alpha.operation.alpha.contents_or_signature_prefix (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_attestation_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.attestation
# bytes in next field	4 bytes	unsigned 30-bit integer
op2	Variable	$alpha.inlined.attestation

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	Variable	$alpha.block_header.alpha.full_header
# bytes in next field	4 bytes	unsigned 30-bit integer
bh2	Variable	$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 at most 20 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_preattestation_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.preattestation
# bytes in next field	4 bytes	unsigned 30-bit integer
op2	Variable	$alpha.inlined.preattestation

Vdf_revelation (tag 8)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
solution	200 bytes	$X_30

Drain_delegate (tag 9)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
consensus_key	21 bytes	$public_key_hash
delegate	21 bytes	$public_key_hash
destination	21 bytes	$public_key_hash

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

Preattestation (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

Attestation (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_attestation (tag 22)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
attestor	21 bytes	$public_key_hash
attestation	Determined from data	$Z.t
level	4 bytes	signed 32-bit integer

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_29

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

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

Update_consensus_key (tag 114)

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
pk	Determined from data	$public_key

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

Smart_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
pvm_kind	1 byte	unsigned 8-bit integer encoding an enumeration (see X_27)
# bytes in next field	4 bytes	unsigned 30-bit integer
kernel	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
parameters_ty	Variable	bytes
? presence of field “whitelist”	1 byte	boolean (0 for false, 255 for true)
whitelist	Determined from data	$X_28

Smart_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 next field	4 bytes	unsigned 30-bit integer
message	Variable	sequence of $X_2

Smart_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
rollup	20 bytes	bytes

Smart_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
rollup	20 bytes	bytes
commitment	76 bytes	$X_25

Smart_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
rollup	20 bytes	bytes
opponent	21 bytes	$public_key_hash
refutation	Determined from data	$X_24

Smart_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
rollup	20 bytes	bytes
stakers	42 bytes	$X_18

Smart_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
rollup	20 bytes	bytes
cemented_commitment	32 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
output_proof	Variable	bytes

Smart_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
staker	21 bytes	$public_key_hash

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_header	97 bytes	$X_17

Zk_rollup_origination (tag 250)

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
public_parameters	Variable	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
circuits_info	Variable	sequence of $X_14
# bytes in next field	4 bytes	unsigned 30-bit integer
init_state	Variable	sequence of bytes
nb_ops	4 bytes	signed 31-bit integer in the range -1073741824 to 1073741823

Zk_rollup_publish (tag 251)

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
zk_rollup	20 bytes	bytes
# bytes in next field	4 bytes	unsigned 30-bit integer
op	Variable	sequence of $X_8

Zk_rollup_update (tag 252)

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
zk_rollup	20 bytes	bytes
update	Determined from data	$X_0

Signature_prefix (tag 255)

Name	Size	Contents
Tag	1 byte	unsigned 8-bit integer
signature_prefix	33 bytes	$bls_signature_prefix