API Reference

Clients

Create the client’s wallet

POST https://mpc-client.portalhq.io/v1/generate This endpoint generates MPC shares for both SECP256K1 (EVM, etc) and ED25519 (Solana, XRP, etc) curves (a Portal wallet).

After receiving MPC shares from this endpoint, be sure to verify the shares with this endpoint before attempting to sign.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Body Parameters

You can leave the request body empty.

{}

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/generate \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

{
  "SECP256K1": {
    "share": "eyJjbG...",
    "id": "cm0r6nkek00ej10dwwx8wdjmf"
  },
  "ED25519": {
    "share": "eyJjbG...",
    "id": "cm0r6nk7c00hbzefaq9s93s0x"
  }
}

Send the client’s assets

POST https://mpc-client.portalhq.io/v1/assets/send This endpoint allows you to easily send a token the client holds to another address.

The Send Assets endpoint builds, signs, and submits a transaction to an RPC gateway.Important: A 200 response only confirms that the transaction was received by the RPC gateway — it does not mean the transaction is confirmed on-chain. The transaction must first be placed in the mempool of the RPC gateway nodes, submitted to miner/validator nodes, and then validated and finalized by the network. This process can take seconds to minutes, depending on the blockchain.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Body Parameters

Name	Type	Description
`share`*	String	The MPC share generated from “Create Wallets” for a specific curve.
`chain`*	String CAIP-2 Chain ID or one of: `"monad-testnet"` `"base"` `"base-sepolia"` `"ethereum"` `"bitcoin-segwit"` `"bitcoin-segwit-testnet"` `"bitcoin-p2wpkh"` `"bitcoin-p2wpkh-testnet"` `"polygon"` `"polygon-amoy"` `"celo"` `"celo-alfajores"` `"sepolia"` `"solana"` `"solana-devnet"` `"stellar"` `"stellar-testnet"` `"tron"` `"tron-nile"` `"tron-shasta"`	The blockchain network.
`to`*	String	The recipient’s address.
`token`*	String	The token contract address (for ERC20 tokens on EVM chains) or the mint address (for Solana SPL tokens). You can also use “USDC” or “USDT” for the respective tokens. For native token transfers, use `"NATIVE"`.
`amount`*	String	The amount of tokens to send (“0.1” is 0.1 USDC)
`rpcUrl`*	String	The RPC node provider URL that the transaction will be submitted through. Not required for Solana or Solana Devnet.
`nonce`	String	The hex string of the nonce to set on the transaction (“0x01” sets the nonce of the transaction to 1). Note that the hex string needs to include the “0x” and for single digits to include a leading zero like “0x0”.
`metadataStr`	String	Optional metadata string for the transaction.

When submitting multiple transactions for a single client in quick succession (or in parallel), each transaction may initially have the same nonce if the blockchain hasn’t processed the earlier ones yet. This can cause errors, as the RPC gateway interprets identical nonces as attempts to overwrite transactions in the mempool.To prevent this, track the nonce in your application and increment it manually for each transaction sent to the Send Assets endpoint, ensuring unique nonces for concurrent requests.

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/assets/send \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{
	"share": "share",
	"chain": "ethereum",
	"to": "0xdFd8302f44727A6348F702fF7B594f127dE3A902",
	"token": "NATIVE",
	"amount": "0.0001"
}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

If your client is using Account Abstraction, then transactionHash is actually a User Operation hash. You can manually look up the user operation hash here.

{
  "transactionHash": "0x02073df9ba08895d681f80ae45440ba57e766602c97ee6321df5ac81bca900cc",
  "metadata": {
    "amount": "0.01",
    "rawAmount": "10000000000000000",
    "tokenAddress": "0xfFf9976782d46CC05630D1f6eBAb18b2324d6B14",
    "tokenDecimals": 18
  }
}

Sign a transaction or message by chain

POST https://mpc-client.portalhq.io/v1/sign This endpoint allows you to sign a transaction or message by chain.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Body Parameters

Name	Type	Description
`method`*	String	The signer RPC method (e.g. “personal_sign”, “eth_sendTransaction”, “sol_signAndSendTransaction”, etc).
`params`*	String	A JSON stringified array of the parameters for the RPC method (e.g. ”[\“test\”]”).
`share`*	String	The MPC share generated from “Create Wallets” for a specific curve.
`chainId`*	String	The blockchain network (a CAIP-2 chain ID like “eip155:10143” for Monad Testnet).
`to`*	String	The recipient’s address.
`rpcUrl`*	String	The node provider RPC URL.
`metadataStr`	String	Optional metadata string for the transaction.

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/sign \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{
	"share": "share",
	"method": "eth_sendTransaction",
	"params": "{\"value\": \"0x01\",\"from\": \"\",\"to\": \"0xdFd8302f44727A6348F702fF7B594f127dE3A902\",\"data\": \"\"}",
	"rpcUrl": "https://api.portalhq.io/rpc/v1/eip155/10143",
	"chainId": "eip155:10143"
}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

{
  "data": "0xf7a6a07fa599db56fca50fa1202670b59054e7ed452ea57b3f5b43148b8bdb165beb3a4b0fd532162a1f0fd475de1a9ecd07c95186f7a0856ce1bffa45e3acc91b"
}

Sign a transaction or message by curve

POST https://mpc-client.portalhq.io/v1/raw/sign/:curve This endpoint allows you to sign a raw message by curve.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Path Parameters

Name	Type	Description
`curve`*	String	The curve you want to use (e.g. `SECP256K1` for EVM chains and `ED25519` for Solana).

Body Parameters

Name	Type	Description
`params`*	String	A hex string of the digest to sign without the leading `0x` (e.g. `"params": "7369676e2074686973"`).
`share`*	String	The MPC share generated from “Create Wallets” for a specific curve.

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/raw/sign/SECP256K1 \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{
	"params": "123",
	"share": "[share]"
}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

The data field is a hex string without the leading 0x.

{
  "data": "f7a6a07fa599db56fca50fa1202670b59054e7ed452ea57b3f5b43148b8bdb165beb3a4b0fd532162a1f0fd475de1a9ecd07c95186f7a0856ce1bffa45e3acc91b"
}

Back up the client’s wallet

POST https://mpc-client.portalhq.io/v1/backup This endpoint allows you to create backup shares for your wallet.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Body Parameters

Name	Type	Description
`generateResponse`*	JSON	The response body from “Create Wallets”.

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/backup \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{
  "generateResponse": "{\"SECP256K1\":{\"share\":\"share\",\"id\":\"shareId\"},\"ED25519\":{\"share\":\"share\",\"id\":\"shareId\"}}"
}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

{
  "SECP256K1": {
    "share": "eyJjbGl...",
    "id": "clu32l6c8008wuvz52jokyo3r"
  },
  "ED25519": {
    "share": "eyJjbGl...",
    "id": "clu32l9310087evz5u5v9k1ao"
  }
}

Recover the client’s wallet

POST https://mpc-client.portalhq.io/v1/recover This endpoint allows you to recover shares for your wallet using your backup shares.

Headers

Name	Type	Description
Authorization*	String	Bearer `<Client API Key>`
Content-Type*	String	application/json

Body Parameters

Name	Type	Description
`backupResponse`*	JSON	The response body from “Back Up Wallets”.

Example Request

Be sure to replace the [token] with either a Client API Key or a Client Session Token.

curl --request POST \
  --url https://mpc-client.portalhq.io/v1/recover \
  --header 'Authorization: Bearer [token]' \
  --header 'Content-Type: application/json' \
  --data '{
  "backupResponse": "{\"SECP256K1\":{\"share\":\"share\",\"id\":\"shareId\"},\"ED25519\":{\"share\":\"share\",\"id\":\"shareId\"}}"
}'

Example Response

200: OK Success
400: Bad Request
401: Unauthorized Request

{
  "SECP256K1": {
    "share": "eyJjbGl...",
    "id": "clu32l6c8008wuvz52jokyo3r"
  },
  "ED25519": {
    "share": "eyJjbGl...",
    "id": "clu32l9310087evz5u5v9k1ao"
  }
}

Getting Started

SDKs

APIs

Integrations

Resources

Clients

Create the client’s wallet

Headers

Body Parameters

Example Request

Example Response

Send the client’s assets

Headers

Body Parameters

Example Request

Example Response

Sign a transaction or message by chain

Headers

Body Parameters

Example Request

Example Response

Sign a transaction or message by curve

Headers

Path Parameters

Body Parameters

Example Request

Example Response

Back up the client’s wallet

Headers

Body Parameters

Example Request

Example Response

Recover the client’s wallet

Headers

Body Parameters

Example Request

Example Response

Getting Started

SDKs

APIs

Integrations

Resources

​Clients

​Create the client’s wallet

Headers

Body Parameters

Example Request

Example Response

​Send the client’s assets

Headers

Body Parameters

Example Request

Example Response

​Sign a transaction or message by chain

Headers

Body Parameters

Example Request

Example Response

​Sign a transaction or message by curve

Headers

Path Parameters

Body Parameters

Example Request

Example Response

​Back up the client’s wallet

Headers

Body Parameters

Example Request

Example Response

​Recover the client’s wallet

Headers

Body Parameters

Example Request

Example Response

Clients

Create the client’s wallet

Send the client’s assets

Sign a transaction or message by chain

Sign a transaction or message by curve

Back up the client’s wallet

Recover the client’s wallet