Bifrost SLPx Stake

Execute Bifrost vETH liquid staking operations: mint, redeem, and claim.

Contract & Network

vETH is deployed on Ethereum and three L2 networks. The same contract address is used across all chains.

Chain	ChainId	VETH Contract	WETH (underlying)	Default RPC	Fallback RPC
Ethereum	1	`0xc3997ff81f2831929499c4eE4Ee4e0F08F42D4D8`	`0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2`	`https://ethereum.publicnode.com`	`https://1rpc.io/eth`
Base	8453	`0xc3997ff81f2831929499c4eE4Ee4e0F08F42D4D8`	`0x4200000000000000000000000000000000000006`	`https://base.publicnode.com`	`https://1rpc.io/base`
Optimism	10	`0xc3997ff81f2831929499c4eE4Ee4e0F08F42D4D8`	`0x4200000000000000000000000000000000000006`	`https://optimism.publicnode.com`	`https://1rpc.io/op`
Arbitrum	42161	`0xc3997ff81f2831929499c4eE4Ee4e0F08F42D4D8`	`0x82aF49447D8a07e3bd95BD0d56f35241523fBab1`	`https://arbitrum-one.publicnode.com`	`https://1rpc.io/arb`

Configuration

On first run, ask the user whether they want to configure custom settings. If not, use the defaults above.

Environment Variables

Variable	Description	Default
`BIFROST_CHAIN`	Target chain name ( `ethereum` , `base` , `optimism` , `arbitrum` )	`ethereum`
`BIFROST_RPC_URL`	Custom RPC endpoint	Per-chain default from table above
`BIFROST_VETH_ADDRESS`	VETH contract address (override)	`0xc3997ff81f2831929499c4eE4Ee4e0F08F42D4D8`
`BIFROST_PRIVATE_KEY`	Private key for agent-side signing (hex, with or without 0x prefix)	Not set (manual signing mode)

Wallet Setup

Two signing modes. Default is manual signing (no setup needed).

Default: Manual Signing

Output complete transaction details (to, value, data, gas, chainId). User signs with their own wallet (MetaMask, Ledger, CLI, etc.).

Option: Agent-Side Signing

Set

BIFROST_PRIVATE_KEY

as an environment variable, or import via Foundry keystore:

bash

cast wallet import bifrost-agent --interactive

When

BIFROST_PRIVATE_KEY

is set, the agent can sign and broadcast transactions directly using

cast send

Quick Reference

Write Operations

Operation	Function	Selector	Description
Mint vETH (via ETH)	`depositWithETH()`	`0x1166dab6`	Stake native ETH to mint vETH. ETH is sent as `msg.value` . The contract wraps ETH → WETH internally — no ERC-20 approval needed. Reverts `EthNotSent()` if `msg.value == 0`
Mint vETH (via WETH)	`deposit(uint256,address)`	`0x6e553f65`	Deposit WETH directly to mint vETH for `receiver` . Requires prior WETH approval to the VETH contract
Redeem vETH	`redeem(uint256,address,address)`	`0xba087652`	Burn `shares` of vETH to initiate ETH withdrawal for `receiver` . ETH enters a redemption queue and is NOT returned instantly. Requires `owner == msg.sender` or sufficient allowance
Claim as ETH	`withdrawCompleteToETH()`	`0x3ec549e9`	Claim ALL completed withdrawals as native ETH. Internally calls `withdrawCompleteTo(this)` then unwraps WETH → ETH. Reverts `EthTransferFailed()` if ETH transfer fails
Claim as WETH	`withdrawComplete()`	`0x266a3bce`	Claim ALL completed withdrawals as WETH to `msg.sender` . Use this if `withdrawCompleteToETH()` fails
Claim to address	`withdrawCompleteTo(address)`	`0xf29ee493`	Claim ALL completed withdrawals as WETH to a specified `receiver` address

Pre-Execution Query Functions

Query	Function	Selector	Description
Preview deposit	`previewDeposit(uint256)`	`0xef8b30f7`	Simulate deposit and return exact vETH shares to be minted
Preview redeem	`previewRedeem(uint256)`	`0x4cdad506`	Simulate redemption and return exact ETH to be returned
Fallback: shares calc	`convertToShares(uint256)`	`0xc6e6f592`	Convert ETH amount to vETH shares using current Oracle exchange rate
Fallback: assets calc	`convertToAssets(uint256)`	`0x07a2d13a`	Convert vETH shares to ETH value using current Oracle exchange rate
vETH balance	`balanceOf(address)`	`0x70a08231`	Get vETH token balance of a specific address
Max redeemable	`maxRedeem(address)`	`0xd905777e`	Maximum vETH shares the owner can redeem in a single tx
Claimable ETH	`canWithdrawalAmount(address)`	`0x52a630b9`	Returns `(totalAvailableAmount, pendingDeleteIndex, pendingDeleteAmount)` . First value = ETH ready to claim

How to Call

Read queries — use

eth_call

(no gas):

bash

# Method A: cast (preferred)
cast call <VETH_CONTRACT> \
  "<FUNCTION_SIGNATURE>(<ARG_TYPES>)(<RETURN_TYPES>)" <ARGS> \
  --rpc-url <RPC_URL>

# Method B: curl (if cast unavailable)
curl -s -X POST <RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"eth_call","params":[{"to":"<VETH_CONTRACT>","data":"<SELECTOR><ENCODED_ARGS>"},"latest"]}'

previewDeposit

previewRedeem

fails, fall back to

convertToShares

convertToAssets

(same encoding).

Write transactions — use

cast send

(requires wallet):

bash

# Mint vETH (stake native ETH)
cast send <VETH_CONTRACT> \
  "depositWithETH()" --value <AMOUNT_IN_WEI> \
  --rpc-url <RPC_URL> --private-key <PRIVATE_KEY>

# Redeem vETH (unstake)
cast send <VETH_CONTRACT> \
  "redeem(uint256,address,address)" <SHARES_IN_WEI> <USER_ADDR> <USER_ADDR> \
  --rpc-url <RPC_URL> --private-key <PRIVATE_KEY>

# Claim ETH (withdraw completed redemptions)
cast send <VETH_CONTRACT> \
  "withdrawCompleteToETH()" \
  --rpc-url <RPC_URL> --private-key <PRIVATE_KEY>

Calldata Encoding (for manual signing output)

uint256: convert wei to hex, left-pad to 64 chars
address: remove 0x prefix, left-pad to 64 chars

canWithdrawalAmount

returns 3 × uint256 (192 hex chars):

(totalAvailableAmount, pendingDeleteIndex, pendingDeleteAmount)

. First 64 chars = claimable ETH amount

API 1: Mint vETH (Stake ETH)

Pre-Execution

Query rate:
```
previewDeposit(amount)
```
→ expected vETH
Check wallet:
```
BIFROST_PRIVATE_KEY
```
env var or Foundry keystore
```
bifrost-agent
```
Display preview and wait for CONFIRM

Transaction

Field	Value
To	`<VETH_CONTRACT>`
Value	User's ETH amount in wei
Data	`0x1166dab6`
ChainId	Per selected chain

Manual Signing Output

To:       <VETH_CONTRACT>
Value:    {wei} ({amount} ETH)
Data:     0x1166dab6
ChainId:  {chainId}

API 2: Redeem vETH (Unstake)

Pre-Execution

Check
```
balanceOf(user)
```
≥ redeem amount
Query
```
previewRedeem(shares)
```
→ expected ETH
Check
```
maxRedeem(user)
```
Display preview (warn: ETH enters queue, NOT instant) and wait for CONFIRM

Transaction

Field	Value
To	`<VETH_CONTRACT>`
Value	`0`
Data	ABI-encoded `redeem(shares, userAddr, userAddr)`
ChainId	Per selected chain

Encode calldata:

cast calldata "redeem(uint256,address,address)" <SHARES> <ADDR> <ADDR>

API 3: Claim Redeemed ETH

Pre-Execution

Check
```
canWithdrawalAmount(user)
```
— first return value = claimable amount
If 0: inform user redemption may still be processing
If > 0: display claimable amount and wait for CONFIRM

Transaction

Field	Value
To	`<VETH_CONTRACT>`
Value	`0`
Data	`0x3ec549e9`
ChainId	Per selected chain

Agent Behavior

Environment check: on first interaction, ask user if they want to configure
```
BIFROST_CHAIN
```
,
```
BIFROST_RPC_URL
```
, or
```
BIFROST_PRIVATE_KEY
```
. If not, use Ethereum Mainnet defaults with manual signing mode
RPC selection: use
```
BIFROST_RPC_URL
```
if set; otherwise use per-chain default RPC. Fall back to per-chain fallback RPC on failure
Multi-chain awareness: when user specifies a chain (e.g. "on Base", "on Arbitrum"), switch to that chain's RPC, WETH address, and chainId accordingly
Wallet detection: check
```
BIFROST_PRIVATE_KEY
```
env var or Foundry keystore
```
bifrost-agent
```
. If found, ask user whether to use it. If not, output tx data for manual signing
CONFIRM required: display transaction preview (amount, rate, expected output, chain) and require user to type CONFIRM before any write
Private key import requires CONFIRM: show security warning first, require CONFIRM before accepting key
Key retention is user-controlled: after tx, ask user whether to keep or delete the key
Balance pre-check: verify sufficient ETH/vETH before building tx
Prefer cast, fall back to curl: use pre-computed calldata from selector table if cast fails
No credential display: never echo private keys; truncate addresses (first 6 + last 4)
Post-completion tip: if no wallet configured, suggest "set up wallet" after operation

After successful tx, provide block explorer link:

https://etherscan.io/tx/{hash}

(Ethereum),

https://basescan.org/tx/{hash}

(Base),

https://optimistic.etherscan.io/tx/{hash}

(Optimism),

https://arbiscan.io/tx/{hash}

(Arbitrum)

Useful links: direct users to Bifrost vETH page or Bifrost App when relevant

Security

Private keys are opt-in only — default outputs unsigned tx data
Explicit CONFIRM for every write operation
Validate amounts against balance and protocol limits
Recommend dedicated wallet with limited funds for agent-side signing

Error Handling

Error	User Message
`EthNotSent()` (0x8689d991)	"No ETH included. Please specify the amount."
`EthTransferFailed()`	"ETH transfer failed. Try claiming as WETH with withdrawComplete()."
`ZeroWithdrawAmount()` (0xd6d9e665)	"No claimable ETH. Your redemption may still be processing."
`ERC4626ExceededMaxRedeem` (0xb94abeec)	"Redeem exceeds your maximum. Check balance."
`Pausable: paused`	"VETH contract is paused. Try again later."
Insufficient ETH	"Insufficient ETH. Balance: {bal}, Needed: {amount + gas}."
Insufficient vETH	"Insufficient vETH. Balance: {bal}, Requested: {amount}."
Max withdraw count exceeded	"Too many pending redemptions. Claim existing ones first."
RPC failure	"Unable to connect. Retrying with backup endpoint..."

Notes

```
depositWithETH()
```
wraps ETH → WETH internally via
```
WETH.deposit()
```
. No ERC-20 approval needed. For direct WETH deposits, use
```
deposit(uint256,address)
```
instead (requires WETH approval)
```
withdrawCompleteToETH()
```
internally calls
```
withdrawCompleteTo(address(this))
```
to receive WETH, then unwraps to ETH via
```
WETH.withdraw()
```
, then sends ETH to caller. If ETH transfer fails, use
```
withdrawComplete()
```
to receive WETH instead
Redemption is NOT instant —
```
redeem()
```
/
```
withdraw()
```
add entries to the withdrawal queue, processed in batches via Bifrost cross-chain mechanism
All write functions are protected by
```
whenNotPaused
```
and
```
nonReentrant
```
(ReentrancyGuardUpgradeable)
Gas estimates are approximate; use
```
cast estimate
```
for accuracy

bifrost-slpx-stake

NPX Install

Tags

SKILL.md Content

Bifrost SLPx Stake

Contract & Network

Configuration

Environment Variables

Wallet Setup

Quick Reference

Write Operations

Pre-Execution Query Functions

How to Call

Calldata Encoding (for manual signing output)

API 1: Mint vETH (Stake ETH)

Pre-Execution

Transaction

Manual Signing Output

API 2: Redeem vETH (Unstake)

Pre-Execution

Transaction

API 3: Claim Redeemed ETH

Pre-Execution

Transaction

Agent Behavior

Security

Error Handling

Notes