feat(tempo): add native multisig account support

.changeset/tempo-multisig-accounts.md

@@ -0,0 +1,5 @@
+---
+"viem": minor
+---
+
+**Tempo:** Added experimental native multisig account support. Use `Account.fromMultisig` (and the re-exported `MultisigConfig` from `ox/tempo`) to derive a multisig sender, prepare a transaction with `multisig: config`, collect owner approvals via `signTransaction`, and broadcast with the collected `signatures`.

package.json

@@ -63,7 +63,7 @@
     "ethers": "^6.15.0",
     "knip": "^5.64.0",
     "micro-eth-signer": "^0.14.0",
-    "ox": "0.14.27",
+    "ox": "0.14.29",
     "permissionless": "^0.2.57",
     "prool": "~0.2.3",
     "publint": "^0.2.12",

site/pages/tempo/accounts/account.fromMultisig.mdx

@@ -0,0 +1,102 @@
+# `Account.fromMultisig`
+
+Instantiates an Account from a [native multisig](https://docs.tempo.xyz/protocol/transactions)
+(`MultisigConfig`) configuration.
+
+:::warning
+**Experimental.** Native multisig support is experimental and may change in a future release.
+It is not yet available on Tempo mainnet or testnet.
+:::
+
+The returned account represents the **multisig sender** – its address is derived from the
+config. It does not hold a key and cannot sign primitives directly (`sign`, `signMessage`,
+`signTypedData` throw). Instead, it is used purely to **broadcast** a multisig transaction:
+it drives the standard [`sendTransaction`](/docs/actions/wallet/sendTransaction) flow,
+passing the prepared request (carrying the collected owner `signatures`) through to the
+chain serializer, which combines the approvals into the multisig signature envelope.
+
+:::tip
+For the full transaction flow (preparing a request, collecting owner approvals, and
+broadcasting), see the [Multisig Transactions](/tempo/guides/multisig-transactions) guide.
+:::
+
+## Usage
+
+```ts twoslash
+import { Account, MultisigConfig } from 'viem/tempo'
+
+const owner_1 = Account.fromSecp256k1(
+  '0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80'
+)
+const owner_2 = Account.fromSecp256k1(
+  '0x59c6995e998f97a5a0044966f0945389dc9e86dae88c7a8412f4603b6b78690d'
+)
+
+// Define the multisig configuration (2-of-2).
+const config = MultisigConfig.from({
+  threshold: 2,
+  owners: [
+    { owner: owner_1.address, weight: 1 },
+    { owner: owner_2.address, weight: 1 },
+  ],
+})
+
+// Instantiate the multisig account.
+const account = Account.fromMultisig(config)
+
+console.log('Address:', account.address)
+```
+
+## Return Type
+
+The return type is backwards compatible with Viem's `Account` type, with the multisig
+`config` attached.
+
+```ts
+type ReturnType = MultisigAccount
+
+type MultisigAccount = Account & {
+  /** Account address, derived from the multisig config. */
+  address: Address
+  /** Multisig config (normalized via `MultisigConfig.from`). */
+  config: MultisigConfig.Config
+  /** Account source. */
+  source: 'multisig'
+  /** Account type. */
+  type: 'local'
+}
+```
+
+:::warning
+`Account.fromMultisig` is for **broadcasting / sender identity** only. Calling `sign`,
+`signMessage`, or `signTypedData` on the returned account throws – owner approvals are
+produced separately by signing a prepared request with an owner account (see
+[Multisig Transactions](/tempo/guides/multisig-transactions)).
+:::
+
+## Parameters
+
+### config
+
+- **Type:** `MultisigConfig.Config`
+
+The multisig configuration, created with `MultisigConfig.from`. The config is normalized
+(owners sorted into canonical ascending order) before the address is derived.
+
+#### config.threshold
+
+- **Type:** `number`
+
+The total owner weight required to authorize a transaction.
+
+#### config.owners
+
+- **Type:** `readonly { owner: Address; weight: number }[]`
+
+The list of owners and their voting weights.
+
+#### config.salt (optional)
+
+- **Type:** `Hex`
+
+Optional salt used to derive a distinct multisig address for the same owner set.

site/pages/tempo/accounts/index.mdx

@@ -1,6 +1,6 @@
 # Accounts
 
-Tempo.ts provides Viem-compatible [Local Accounts](https://viem.sh/docs/accounts/local) that support multiple signature schemes including **secp256k1**, **P256**, and **WebAuthn (passkeys)**. 
+Tempo.ts provides Viem-compatible [Local Accounts](https://viem.sh/docs/accounts/local) that support multiple signature schemes including **secp256k1**, **P256**, and **WebAuthn (passkeys)**, as well as **native multisig** accounts. 
 
 These accounts are fully backwards compatible with Viem APIs, meaning you can use them any Viem Action that accepts an `account`.
 
@@ -38,3 +38,4 @@ const hash = await client.sendTransactionSync({
 | [`fromWebAuthnP256`](/tempo/accounts/account.fromWebAuthnP256) | Create an account from a WebAuthn credential (passkeys) |
 | [`fromWebCryptoP256`](/tempo/accounts/account.fromWebCryptoP256) | Create an account from a WebCrypto P256 key pair |
 | [`fromP256`](/tempo/accounts/account.fromP256) | Create an account from a P256 private key |
+| [`fromMultisig`](/tempo/accounts/account.fromMultisig) | Create an account from a native multisig configuration |