Cosmos (ATOM)

Sign Cosmos SDK transactions from an Amino SignDoc. The bridge accepts the Amino input, re-encodes its fields as a Protobuf SignDoc and signs in SIGN_MODE_DIRECT. Fetch account_number / sequence from a REST endpoint yourself — the bridge never does. DCENT signs the amounts, addresses, account_number, sequence and chain_id exactly as sent (a non-string chain_id is signed as an empty string), so placeholder values produce a signature that cannot be broadcast (see the field table). chain_id is not checked against your request chainId — keep them consistent. The fee denom and a native transfer denom are not read: the bridge always uses the chain's base denom (uatom / ucore / ahp; utestcore on Coreum testnet); a token denom (any denom containing /, such as ibc/… or factory/…, or an AssetFT subunit-issuer) is used as the token, and it must resolve to a token DCENT supports (or a Coreum form-D descriptor), otherwise -32602.

Field	Value
Family	Cosmos
coinType	118
keyPath	m/44'/118'/<accountIdx>'/0/0
chainId	cosmos:cosmoshub-4/slip44:118

Supported Methods

Method	Supported
getAddress	✓
signTransaction	✓
signMessage	—
signTypedData	—
signData	✗

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	2.21.0 or higher	1.0.0 or higher
signTransaction	2.21.0 or higher	1.0.0 or higher

info

Firmware versions above are for the DCENT Biometric Wallet line — DCENT X supports them from 1.0.0. COREUM smart-token support was added in firmware 2.28.1.

getAddress — account address

Retrieves the Cosmos account address (the pubkey field may be empty — use getPublicKey for the public key). Cosmos uses bech32 addresses with a chain-specific prefix (cosmos1… on the Hub).

Field	Type	Required	Source	Notes
chainId	string	Required	App	Full CAIP-19, e.g. cosmos:cosmoshub-4/slip44:118
keyPath	string	Required	App	BIP-44, e.g. m/44'/118'/0'/0/0

Request

await dcent.getAddress({
  chainId: 'cosmos:cosmoshub-4/slip44:118',
  keyPath: "m/44'/118'/0'/0/0"
})

Response

Field	Type	Notes
body.parameter.address	string	bech32 account address (cosmos1… on the Hub)
body.parameter.pubkey	hex	0x-prefixed. DCENT X returns it empty ("0x") — do not rely on it; use getPublicKey for the public key

{
  "header": {
    "version": "1.0",
    "status": "success",
    "response_from": "getAddress"
  },
  "body": {
    "command": "getAddress",
    "parameter": {
      "address": "cosmos1…",
      "pubkey": "0x"
    }
  }
}

signTransaction — Amino SignDoc

payload.transaction:

{
  "chain_id": "cosmoshub-4",
  "account_number": "12345",
  "sequence": "0",
  "fee": {
    "amount": [
      {
        "denom": "uatom",
        "amount": "5000"
      }
    ],
    "gas": "200000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "cosmos1<sender>",
        "to_address": "cosmos1<recipient>",
        "amount": [
          {
            "denom": "uatom",
            "amount": "1000000"
          }
        ]
      }
    }
  ],
  "memo": ""
}

Field	Required	Source	Unit	Notes
chain_id	Required-Real	App	—	e.g. cosmoshub-4. Not validated — signed as sent (an omitted or non-string value is signed as an empty string)
account_number / sequence	Required-Real	App	—	Real, current values — the app must supply them; sender must exist on-chain
msgs[].value.from_address	Required-Real	Wallet	—	Device cosmos account
msgs[].type	Required	App	—	cosmos-sdk/MsgSend or /cosmos.bank.v1beta1.MsgSend — another type, or more than one message, → -32601; missing → -32602
msgs[].value.to_address	Required	App	—	Recipient (cosmos1…). Missing → -32602
amount[].amount	Required	App	uatom	1 ATOM = 1e6. Exactly one coin — more than one → -32602
amount[].denom / fee.amount[].denom	—	App	—	Not read for a native transfer — uatom is always used
fee.amount[].amount	Optional	App	uatom	Total fee. If omitted, the fee is signed as 0 — send a real fee
fee.gas	Required	App	—	Gas limit. Missing → -32602
memo	Optional	App	—

Response

Field	Type	Notes
header.status	string	"success" on completion
body.parameter.signature	string	Dot-joined string <signature>.<pubkey>.<txRaw> from a SIGN_MODE_DIRECT (Protobuf SignDoc) signature, not a bare signature. The last part is the signed Protobuf TxRaw in hex — convert it to base64 and send it as tx_bytes to /cosmos/tx/v1beta1/txs to broadcast. The pubkey part can be empty

{
  "header": {
    "version": "1.0",
    "status": "success",
    "response_from": "signTransaction"
  },
  "body": {
    "command": "signTransaction",
    "parameter": {
      "signature": "<signature>.<pubkey>.<txRaw hex>"
    }
  }
}

signTransaction — other networks & tokens

The same Amino MsgSend envelope signs other Cosmos SDK chains and AssetFT tokens — the chain_id, the address prefix (cosmos1 / core1 / hippo1) and the token denom change. Fees stay in each chain’s native denom. Custom (unregistered) tokens use a compact token descriptor on Coreum only — an unregistered token on Cosmos Hub or Hippo Protocol is rejected with -32602.

info

Testnet variants share the same shape: Coreum testnet cosmos:coreum-testnet-1/slip44:990 (denom utestcore), Hippo testnet cosmos:hippo-protocol-testnet-1/slip44:118 (denom ahp).

Coreum — native (TX) transfer

chainId cosmos:coreum-mainnet-1/slip44:990 · coinType 990 · keyPath m/44'/990'/0'/0/0 · denom ucore (1 TX = 1e6 ucore) · MsgSend

payload.transaction:

{
  "chain_id": "coreum-mainnet-1",
  "account_number": "12345",
  "sequence": "0",
  "fee": {
    "amount": [
      {
        "denom": "ucore",
        "amount": "5000"
      }
    ],
    "gas": "200000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
        "to_address": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
        "amount": [
          {
            "denom": "ucore",
            "amount": "1000000"
          }
        ]
      }
    }
  ],
  "memo": ""
}

Field	Type	Required	Notes
chain_id	string	Required-Real	Cosmos SDK chain id (bare, not CAIP), e.g. coreum-mainnet-1. Not validated — an omitted or non-string value is signed as an empty string.
account_number / sequence	string	Required-Real	Real, current values — the app must supply them; not auto-filled.
fee.amount[].denom	string	—	Not read — the fee is always in native ucore.
fee.amount[].amount / fee.gas	string	fee.gas Required (-32602 if missing); amount Optional (signed as 0 if omitted)	Fee amount and gas limit, base units.
msgs[].type	string	Required	cosmos-sdk/MsgSend — bank send.
msgs[].value.from_address	string	Required-Real	Device Coreum account that signs (core1…; testcore1… on Coreum testnet).
msgs[].value.to_address	string	Required	Recipient address (core1…; testcore1… on Coreum testnet).
msgs[].value.amount[].denom	string	—	Not read for a native transfer — ucore is always used (1 TX = 1e6 ucore). A token denom makes it a token transfer (below).
msgs[].value.amount[].amount	string	Required	Value in base units.
memo	string	Optional	Optional Cosmos memo; empty string by default.

Coreum AssetFT (smart-token) transfer

info

Token model: registered AssetFT denom. A token denom on DCENT's supported list is resolved from the registry and signed with its registered symbol and decimals. For a token that is not on the list, use the form-D descriptor below with decimals (Coreum only). See Core Concepts → Token descriptors.

Same bank MsgSend, but msgs[].value.amount[].denom is the AssetFT token denom (subunit-issuer) instead of native ucore — the bridge resolves it to the registered smart-token and signs a token transfer, not a native transfer. The fee is always paid in native ucore. amount "1000000" = 1 token at 6 decimals.

payload.transaction:

{
  "chain_id": "coreum-mainnet-1",
  "account_number": "12345",
  "sequence": "0",
  "fee": {
    "amount": [
      {
        "denom": "ucore",
        "amount": "5000"
      }
    ],
    "gas": "200000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
        "to_address": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
        "amount": [
          {
            "denom": "test-core14ljz7w9lc2yrg66gtfklk94p4jzzmla32ft2s8",
            "amount": "1000000"
          }
        ]
      }
    }
  ],
  "memo": ""
}

Field	Type	Required	Notes
chain_id	string	Required-Real	coreum-mainnet-1. Not validated — signed as sent (a non-string value is signed as an empty string).
msgs[].type	string	Required	cosmos-sdk/MsgSend — bank send is reused for AssetFT tokens.
msgs[].value.from_address	string	Required-Real	Device Coreum account that signs.
msgs[].value.to_address	string	Required	Recipient (core1…; testcore1… on Coreum testnet).
msgs[].value.amount[].denom	string	Required-Real	AssetFT token denom (subunit-issuer, e.g. test-core14ljz…) — non-native; the bridge resolves it to the registered smart-token. If omitted, the amount is signed as a native ucore transfer instead.
msgs[].value.amount[].amount	string	Required	Token amount in base units ("1000000" = 1 token @ 6 decimals).
fee.amount[].denom	string	—	Not read — the fee is always paid in native ucore, not the token.
account_number / sequence	string	Required-Real	Real, current values — the app must supply them; not auto-filled.
memo	string	Optional	Optional.

Hippo Protocol — HP transfer

chainId cosmos:hippo-protocol-1/slip44:118 · coinType 118 · keyPath m/44'/118'/0'/0/0 · denom ahp · MsgSend

payload.transaction:

{
  "chain_id": "hippo-protocol-1",
  "account_number": "12345",
  "sequence": "0",
  "fee": {
    "amount": [
      {
        "denom": "ahp",
        "amount": "5000"
      }
    ],
    "gas": "200000"
  },
  "msgs": [
    {
      "type": "cosmos-sdk/MsgSend",
      "value": {
        "from_address": "hippo1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqztkyex",
        "to_address": "hippo1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqztkyex",
        "amount": [
          {
            "denom": "ahp",
            "amount": "1000000"
          }
        ]
      }
    }
  ],
  "memo": ""
}

Field	Type	Required	Notes
chain_id	string	Required-Real	Cosmos SDK chain id (bare, not CAIP), e.g. hippo-protocol-1. Not validated — an omitted or non-string value is signed as an empty string.
account_number / sequence	string	Required-Real	Real, current values — the app must supply them; not auto-filled.
fee.amount[].denom	string	—	Not read — the fee is always in native ahp.
fee.amount[].amount / fee.gas	string	fee.gas Required (-32602 if missing); amount Optional (signed as 0 if omitted)	Fee amount and gas limit, base units.
msgs[].type	string	Required	cosmos-sdk/MsgSend — bank send.
msgs[].value.from_address	string	Required-Real	Device Hippo account that signs (hippo1…).
msgs[].value.to_address	string	Required	Recipient address (hippo1…).
msgs[].value.amount[].denom	string	—	Not read for a native transfer — ahp is always used.
msgs[].value.amount[].amount	string	Required	Value in base units.
memo	string	Optional	Optional Cosmos memo; empty string by default.

AssetFT — form-D descriptor

Skip hand-built messages: pass a compact token object { contract, to, amount, decimals } and the bridge wraps it into an Amino MsgSend whose denom is the contract. from identifies the signer; amount is in base units (not rescaled by decimals). Coreum only — coreum-mainnet-1 or coreum-testnet-1; an unregistered token on Cosmos Hub or Hippo Protocol is rejected with -32602.

payload.transaction:

{
  "token": {
    "contract": "txd-core1pjt5jvv7dwmr5pfk5ecc5mc38rahas7d90vklk",
    "to": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
    "amount": "1000000",
    "decimals": 6,
    "symbol": "TXD"
  },
  "from": "core1qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqdcyqx",
  "chain_id": "coreum-mainnet-1",
  "account_number": "12345",
  "sequence": "0",
  "fee": {
    "amount": [
      {
        "denom": "ucore",
        "amount": "5000"
      }
    ],
    "gas": "200000"
  },
  "memo": ""
}

Field	Type	Required	Notes
token.contract	string	Required	AssetFT denom / contract to send; used verbatim as the MsgSend denom. Unregistered tokens allowed.
token.to	string	Required	Recipient (core1…; testcore1… on Coreum testnet).
token.amount	string	Required	Amount in base units (not rescaled by decimals).
token.decimals	number	Optional (Required for an unregistered token)	Base-unit exponent; enables descriptor resolution (no on-chain RPC). An unregistered token without token.decimals is rejected with -32602.
token.symbol	string	Optional	Display metadata only.
from	string	Required-Real	Device Coreum account that signs (read-only signer).
chain_id	string	Required-Real	coreum-mainnet-1 (Coreum mainnet) or coreum-testnet-1 (Coreum testnet). Not validated — signed as sent (a non-string value is signed as an empty string).
account_number / sequence	string	Required-Real	Real, current values — the app must supply them; not auto-filled.
fee.amount[].amount / fee.gas	string	fee.gas Required (-32602 if missing); amount Optional (signed as 0 if omitted)	Fee in the native denom — ucore, or utestcore on testnet (the fee denom is not read).
memo	string	Optional	Optional.

info

Signable scope — single bank MsgSend only. The bridge signs exactly one /cosmos.bank.v1beta1.MsgSend. It takes an Amino StdSignDoc (message type cosmos-sdk/MsgSend or /cosmos.bank.v1beta1.MsgSend) and signs it in SIGN_MODE_DIRECT. Protobuf SignDoc input (bodyBytes / authInfoBytes) is not supported: a message that is not a single MsgSend is rejected with -32601, and otherwise the request is rejected with -32602 unless you also send top-level account_number, sequence and fee.gas — in which case it is signed with sequence 0 and fee 0, which is not a valid transaction. Send an Amino StdSignDoc with top-level account_number / sequence. Token transfers reuse the same MsgSend, carrying the token's denom — DCENT's supported list holds Coreum AssetFT (subunit-issuer) tokens; any other denom needs a Coreum form-D descriptor. Any other message type — CW20 MsgExecuteContract, IBC MsgTransfer, staking / governance — and any multi-message tx are rejected with -32601 ("Method not found"); a malformed SignDoc (empty/undecodable msgs, missing from/to/amount) returns -32602, and a payload with neither msgs nor bodyBytes, and no string sender field, returns -32601. CW20 / IBC transfer messages are not yet wired.

Common Mistakes

danger

Sender not on-chain — REST lookup 404s for unfunded accounts. Amounts not in micro-units (uatom).

• signTransaction
• Known Differences