VeChain (VET)

Sign VeChain Thor transactions. The app builds a Thor transaction (thor-devkit shape) with one or more clauses; the device signs the transaction hash by its keyPath. Note: only the first clause is used.

Field	Value
Family	VeChain
coinType	818
keyPath	m/44'/60'/<accountIdx>'/0/0
amount unit	wei
chainId	vechain:b1ac3413d346d43539627e6be7ec1b4a/slip44:818

Supported Methods

Method	Supported
getAddress	✓
signTransaction	✓
signMessage	✗
signTypedData	✗

Requirements

Minimum firmware for each method. The two models are on different version lines, so DCENT Biometric Wallet and DCENT X are listed separately (the numbers are not comparable across models). Below this the request returns the firmware-update error (5005) and the bridge prompts to update.

Method	DCENT Biometric Wallet	DCENT X
getAddress	2.23.4 or higher	1.0.0 or higher
signTransaction	2.23.4 or higher	1.0.0 or higher

info

VeChain derives its address on the EVM coinType 60 path (m/44'/60'/0'/0/0) even though its SLIP-44 coinType is 818. The chainId on the wire is always the full vechain:b1ac3413d346d43539627e6be7ec1b4a/slip44:818.

getAddress — account address

Retrieves the VeChain address. Returns a 0x address (same key as the EVM derivation).

Field	Type	Required	Source	Notes
chainId	string	Required	App	Full CAIP-19 — vechain:b1ac3413d346d43539627e6be7ec1b4a/slip44:818
keyPath	string	Required	App	BIP-32 path; VeChain uses the EVM coinType 60 path (m/44'/60'/0'/0/0)

Request

await dcent.getAddress({
  chainId: 'vechain:b1ac3413d346d43539627e6be7ec1b4a/slip44:818',
  keyPath: "m/44'/60'/0'/0/0"
})

Response

Field	Type	Notes
header.status	string	"success" on success
body.command	string	"getAddress"
body.parameter.address	hex addr	The VeChain account address — an EVM-style 0x-prefixed 20-byte hex string (same key as the EVM derivation). VeChain has no address variants, so no addressFormat is needed.

{
  "header": {
    "version": "1.0",
    "status": "success"
  },
  "body": {
    "command": "getAddress",
    "parameter": {
      "address": "0x6A5C…"
    }
  }
}

signTransaction — Thor transaction

Signs a VeChain Thor transaction. Returns the signed raw transaction ready to broadcast.

Payload — native VET transfer

payload.transaction:

{
  "chainTag": 74,
  "blockRef": "0x0000000000000000",
  "expiration": 720,
  "clauses": [
    {
      "to": "0xcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd",
      "value": "0x10",
      "data": "0x"
    }
  ],
  "gasPriceCoef": 0,
  "gas": 21000,
  "fee": "210000000000000000",
  "dependsOn": null,
  "nonce": "0x0"
}

Field	Type	Required	Source	Unit	Notes
chainTag	number	Required	App	—	Network tag (74 = mainnet) — last byte of the genesis block id
blockRef	hex	Required-Real	App	—	Real reference block — the app must supply it (non-zero); not auto-filled
expiration	number	Required	App	blocks	Block count the tx stays valid after blockRef
clauses[].to	hex addr	Required-Real	App	—	Recipient (native) or token contract (VIP-180)
clauses[].value	hex	Required	App	wei	VET amount; 0x0 for token transfers (amount lives in data)
clauses[].data	hex	Optional	App	—	0x for native; calldata for contracts (opaque pass-through)
gasPriceCoef	number	Required	App	—	Gas price coefficient (0–255)
gas	number	Required-Real	App	—	Gas limit; app estimate
fee	string	Required-Real	App	—	Total VTHO in wei-scale (display only — not part of the signed RLP). Paired with gas by the fee gate; omitting it fails with -32602
dependsOn	hex / null	Optional	App	—	Tx id this tx depends on, or null
nonce	hex	Required	App	—	Transaction nonce

Request

await dcent.sign({
  method: 'signTransaction',
  chainId: 'vechain:b1ac3413d346d43539627e6be7ec1b4a/slip44:818',
  payload: {
    keyPath: "m/44'/60'/0'/0/0",
    transaction: {
      chainTag: 74,
      blockRef: '0x0000000000000000',
      expiration: 720,
      clauses: [
        {
          to: '0xcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcdcd',
          value: '0x10',
          data: '0x'
        }
      ],
      gasPriceCoef: 0,
      gas: 21000,
      fee: '210000000000000000',
      dependsOn: null,
      nonce: '0x0'
    }
  }
})

Response

Field	Type	Notes
header.status	string	"success" on success
body.command	string	"signTransaction"
body.parameter.signature	hex	The broadcast-ready signed raw Thor transaction (RLP-encoded), not a bare signature. Broadcast this value as-is to a Thor node — do not re-encode it.

{
  "header": {
    "version": "1.0",
    "status": "success"
  },
  "body": {
    "command": "signTransaction",
    "parameter": {
      "signature": "0xf8…"
    }
  }
}   // signed raw tx

Variant — VIP-180 token transfer a9059cbb

info

Token model: form-D descriptor. Always send the token under transaction.token with its symbol and trustworthy decimals (read from the chain yourself) — the bridge signs with no network access and never looks symbol / decimals up, so without the descriptor it fails closed with -32602. See Core Concepts → Token descriptors.

VIP-180 is VeChain's ERC-20-compatible token standard (e.g. VTHO, contract 0x0000000000000000000000000000456E65726779). The token amount lives in data; value stays 0x0.

payload.transaction:

{
  "chainTag": 74,
  "blockRef": "0x0000000000000000",
  "expiration": 720,
  "clauses": [
    {
      "to": "0x0000000000000000000000000000456E65726779",
      "value": "0x0",
      "data": "0xa9059cbb<recipient 32B><amount 32B>"
    }
  ],
  "gasPriceCoef": 0,
  "gas": 80000,
  "fee": "800000000000000000",
  "dependsOn": null,
  "nonce": "0x0"
}

• clauses[0].to = the token contract (not the recipient). Required-Real
• clauses[0].value = 0x0 (token amount is encoded in data).
• clauses[0].data = selector 0xa9059cbb + recipient (32B, left-padded) + amount (32B, token base units). Example amount 0x3e8 = 1000 base units.

info

Single-clause; VIP-180 identified. The bridge uses only clauses[0] — multi-clause batches are not supported. VIP-180 token transfers are now identified (m02-05-75): the bridge decodes the transfer(recipient,amount) calldata via extractVechainTokenIdentity and synthesizes a TokenAccount, so the device shows the token symbol/amount — no longer opaque. A token still signs, but only with a form-D descriptor that carries decimals — the bridge signs with no network access and never looks the metadata up for you. If it can resolve neither (no descriptor) or the calldata is malformed it fail-closes with -32602, so a token transfer is never blind-signed as a 0-VET native tx. Non-token clause data stays opaque. (the bridge)

Variant — VIP-180 form-D descriptor

Send a compact token descriptor instead of building clauses yourself. The bridge ABI-encodes a9059cbb transfer(address,uint256) from { contract, to, amount } and emits a single clause { to: contract, value: "0", data }. Your envelope fields (chainTag, blockRef, expiration, gas, gasPriceCoef, fee, nonce, dependsOn) are preserved. amount is a base-unit string (not rescaled by decimals).

payload.transaction:

{
  "chainTag": 74,
  "blockRef": "0x00b3c1e4a5f6d7e8",
  "expiration": 720,
  "token": {
    "contract": "0x4e17357053da4b473e2daa2c65c2c949545724b8",
    "to": "0x0000000000000000000000000000000000000000",
    "amount": "1000",
    "decimals": 6,
    "symbol": "VeUSD"
  },
  "gasPriceCoef": 0,
  "gas": 80000,
  "fee": "800000000000000000",
  "dependsOn": null,
  "nonce": "0x0"
}

Field	Type	Required	Notes
token.contract	string	Required	VIP-180 contract; must match 0x + 40 hex chars. Unregistered tokens allowed.
token.to	string	Required	Recipient; also validated as 0x + 40 hex so a malformed address is rejected instead of silently padded.
token.amount	string	Required	Base-unit integer string, must fit uint256; not rescaled by decimals. 0 is allowed.
token.decimals	number	Required	Base-unit exponent; enables descriptor resolution on the device.
token.symbol	string	Optional	Display metadata only.
blockRef	string	Required-Real	8-byte block reference. The bridge does not refresh it — send a fresh value.
gas / fee	number / string	Required	Map to the fee gate (gasLimit / fee). fee is the total in wei-scale VTHO.
chainTag / expiration / gasPriceCoef / nonce / dependsOn	mixed	Required	Thor envelope fields; passed through into the signed RLP.

info

Verified on device (2026-07-20): this descriptor displays as VeUSD 0.001 — amount "1000" at decimals 6. Note that fee is display-only; it is not part of the signed RLP (VeChain derives the actual cost from gas and gasPriceCoef on-chain).

Common Mistakes

danger

Wrong keyPath — VeChain uses the EVM path m/44'/60'/0'/0/0, not m/44'/818'/…. Stale blockRef — refresh blockRef (and nonce) immediately before signing or the tx expires. Multiple clauses — only the first clause is signed; extra clauses are ignored. VIP-180 to set to the recipient instead of the token contract, with the amount left out of data.

• signTransaction (index)
• getAddress
• Known Differences