Sablier Vesting Skill

You are an AI agent that creates and manages token vesting streams on EVM-compatible blockchains using the Sablier Lockup v3.0 protocol. Sablier is a token streaming protocol where the creator locks up ERC-20 tokens in a smart contract and the recipient's allocation increases every second until the stream ends.

When To Use This Skill

Use this skill when the user asks you to:

• Create a token vesting stream (linear, dynamic, or tranched)
• Lock tokens in a vesting contract
• Set up employee vesting, investor vesting, or airdrop distribution
• Stream tokens to a recipient over time
• Cancel, withdraw from, or manage an existing Sablier stream

Security: Private Key and Secret Handling

These rules are mandatory. Follow them in every interaction.

Agent Behavioral Constraints

1. NEVER ask the user to paste a private key into the chat. If the user volunteers a raw private key in a message, warn them immediately that it may be logged and recommend they rotate it.
2. NEVER embed a raw private key in any command you execute. Always use an environment variable reference ($PRIVATE_KEY, $ETH_PRIVATE_KEY) or a secure signing method instead.
3. NEVER log, echo, or print a private key or mnemonic to stdout, a file, or any other output.
4. Always recommend the safest available signing method, in this order of preference:
   • Hardware wallet: --ledger or --trezor flags (most secure, no key exposure)
   • Foundry keystore (cast wallet import): --account <name> (encrypted on disk, password-prompted at sign time)
   • Environment variable: --private-key $ETH_PRIVATE_KEY (key stays in the shell environment, never appears in command text)
   • Raw --private-key 0x...: Discourage this. Only acceptable for throwaway testnets where the key holds no real value.

Setting Up Secure Signing

Option 1 -- Hardware wallet (recommended for mainnet):

No setup required. Just add --ledger or --trezor to any cast send / forge script command.

Option 2 -- Foundry encrypted keystore (recommended default):

# Import a key once (you'll be prompted for the private key and an encryption password)
cast wallet import my-deployer --interactive

# Then use it in any command
cast send ... --account my-deployer

The key is stored encrypted at ~/.foundry/keystores/my-deployer. You only type your password at sign time; the private key is never exposed in shell history or process arguments.

Option 3 -- Environment variable (acceptable):

# Export in your shell session (not in a file that gets committed)
export ETH_PRIVATE_KEY=0x...

# Reference the variable (the key value never appears in the command itself)
cast send ... --private-key $ETH_PRIVATE_KEY

RPC URL Handling

RPC URLs may contain API keys. Follow the same principles:

# Set once in your shell
export ETH_RPC_URL=https://eth-mainnet.g.alchemy.com/v2/<YOUR_KEY>

# cast and forge automatically read ETH_RPC_URL, so --rpc-url can be omitted
cast send <ADDRESS> "approve(address,uint256)" ...

Alternatively, configure the RPC in foundry.toml under [rpc_endpoints].

Core Concepts

Stream Types

Sablier Lockup v3.0 uses a single unified SablierLockup contract per chain. There are three stream models:

Stream Shapes

• Linear: Constant payment rate (identity function). Good for salaries and simple vesting.
• Cliff Unlock: No tokens available before the cliff; linear streaming after. Great for employee vesting (e.g. 1-year cliff + 3 years linear).
• Initial Unlock: Immediate release of some tokens + linear vesting for the rest. Good for signing bonuses.
• Exponential: Recipient gets increasingly more tokens over time. Good for airdrops to incentivize long-term holding.
• Unlock in Steps: Traditional periodic unlocks (weekly/monthly/yearly). Good for investor vesting.
• Unlock Monthly: Tokens unlock on the same day every month. Good for salaries and ESOPs.
• Backweighted: Little vests early, large chunks towards the end (e.g. 10%/20%/30%/40% over 4 years).
• Timelock: All tokens locked until a specific date, then fully released.

Deployment Addresses (Lockup v3.0)

All chains use the same contract pattern. Key mainnet deployments:

For testnets, see: https://docs.sablier.com/guides/lockup/deployments

Step-by-Step: Creating a Vesting Stream with cast

The preferred method is using Foundry's cast CLI tool which the agent has access to.

Prerequisites

1. The sender must have the ERC-20 tokens in their wallet.
2. The sender must approve the SablierLockup contract to spend the tokens.
3. You need: RPC URL, a signing method (keystore, hardware wallet, or env var), token address, recipient address.
4. Ask the user which signing method they prefer before constructing commands. Default to --account <KEYSTORE_NAME> if they have one set up, or --ledger for mainnet. See the Security section above.

Step 1: Approve the Token

cast send <TOKEN_ADDRESS> \
  "approve(address,uint256)" \
  <SABLIER_LOCKUP_ADDRESS> <AMOUNT_IN_WEI> \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Step 2: Create the Stream

Option A: Linear Stream (createWithDurationsLL)

This creates a linear vesting stream. The CreateWithDurations struct is ABI-encoded as a tuple.

Parameters for createWithDurationsLL:

function createWithDurationsLL(
    Lockup.CreateWithDurations calldata params,
    LockupLinear.UnlockAmounts calldata unlockAmounts,
    LockupLinear.Durations calldata durations
) external returns (uint256 streamId);

Where:

• Lockup.CreateWithDurations = (address sender, address recipient, uint128 depositAmount, address token, bool cancelable, bool transferable, string shape)
• LockupLinear.UnlockAmounts = (uint128 start, uint128 cliff)
• LockupLinear.Durations = (uint40 cliff, uint40 total)

Example: 1-year linear vesting of 10,000 tokens with no cliff:

# Calculate values
# 10000 tokens with 18 decimals = 10000000000000000000000
# 52 weeks in seconds = 31449600

cast send <SABLIER_LOCKUP_ADDRESS> \
  "createWithDurationsLL((address,address,uint128,address,bool,bool,string),(uint128,uint128),(uint40,uint40))" \
  "(<SENDER>,<RECIPIENT>,10000000000000000000000,<TOKEN>,true,true,)" \
  "(0,0)" \
  "(0,31449600)" \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Example: 4-year vesting with 1-year cliff:

# cliff = 365 days = 31536000 seconds
# total = 4 years = 126144000 seconds

cast send <SABLIER_LOCKUP_ADDRESS> \
  "createWithDurationsLL((address,address,uint128,address,bool,bool,string),(uint128,uint128),(uint40,uint40))" \
  "(<SENDER>,<RECIPIENT>,<AMOUNT_WEI>,<TOKEN>,true,true,)" \
  "(0,0)" \
  "(31536000,126144000)" \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Example: With initial unlock of 1000 tokens and cliff unlock of 2000 tokens (out of 10000 total):

cast send <SABLIER_LOCKUP_ADDRESS> \
  "createWithDurationsLL((address,address,uint128,address,bool,bool,string),(uint128,uint128),(uint40,uint40))" \
  "(<SENDER>,<RECIPIENT>,10000000000000000000000,<TOKEN>,true,true,)" \
  "(1000000000000000000000,2000000000000000000000)" \
  "(31536000,126144000)" \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Option B: Tranched Stream (createWithDurationsLT)

For periodic unlocks (monthly, quarterly, etc.).

function createWithDurationsLT(
    Lockup.CreateWithDurations calldata params,
    LockupTranched.TrancheWithDuration[] calldata tranches
) external returns (uint256 streamId);

Where TrancheWithDuration = (uint128 amount, uint40 duration)

Example: 4 quarterly unlocks of 2500 tokens each:

# Each quarter ≈ 13 weeks = 7862400 seconds

cast send <SABLIER_LOCKUP_ADDRESS> \
  "createWithDurationsLT((address,address,uint128,address,bool,bool,string),(uint128,uint40)[])" \
  "(<SENDER>,<RECIPIENT>,10000000000000000000000,<TOKEN>,true,true,)" \
  "[(2500000000000000000000,7862400),(2500000000000000000000,7862400),(2500000000000000000000,7862400),(2500000000000000000000,7862400)]" \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Option C: Dynamic Stream (createWithTimestampsLD)

For exponential curves and custom distribution.

function createWithTimestampsLD(
    Lockup.CreateWithTimestamps calldata params,
    LockupDynamic.Segment[] calldata segments
) external returns (uint256 streamId);

Where:

• Lockup.CreateWithTimestamps = (address sender, address recipient, uint128 depositAmount, address token, bool cancelable, bool transferable, (uint40,uint40) timestamps, string shape)
• Lockup.Timestamps = (uint40 start, uint40 end)
• LockupDynamic.Segment = (uint128 amount, UD2x18 exponent, uint40 timestamp)

Example: Exponential stream (2 segments):

# Get current timestamp
CURRENT_TS=$(cast block latest --rpc-url <RPC_URL> -f timestamp)
START_TS=$((CURRENT_TS + 100))
MID_TS=$((CURRENT_TS + 2419200))   # +4 weeks
END_TS=$((CURRENT_TS + 31449600))  # +52 weeks

cast send <SABLIER_LOCKUP_ADDRESS> \
  "createWithTimestampsLD((address,address,uint128,address,bool,bool,(uint40,uint40),string),(uint128,uint64,uint40)[])" \
  "(<SENDER>,<RECIPIENT>,<DEPOSIT_AMOUNT>,<TOKEN>,true,true,($START_TS,$END_TS),)" \
  "[(<AMOUNT_0>,1000000000000000000,$MID_TS),(<AMOUNT_1>,3140000000000000000,$END_TS)]" \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Note: The exponent in segments uses UD2x18 format (18 decimals). 1e18 = linear, 2e18 = quadratic, 3.14e18 = steeper curve.

Managing Existing Streams

Check Stream Status

cast call <SABLIER_LOCKUP_ADDRESS> "statusOf(uint256)(uint8)" <STREAM_ID> --rpc-url <RPC_URL>

Status values: 0=PENDING, 1=STREAMING, 2=SETTLED, 3=CANCELED, 4=DEPLETED

Check Withdrawable Amount

cast call <SABLIER_LOCKUP_ADDRESS> "withdrawableAmountOf(uint256)(uint128)" <STREAM_ID> --rpc-url <RPC_URL>

Withdraw from Stream (recipient)

# First, calculate the minimum fee
FEE=$(cast call <SABLIER_LOCKUP_ADDRESS> "calculateMinFeeWei(uint256)(uint256)" <STREAM_ID> --rpc-url <RPC_URL>)

cast send <SABLIER_LOCKUP_ADDRESS> \
  "withdrawMax(uint256,address)" \
  <STREAM_ID> <RECIPIENT_ADDRESS> \
  --value $FEE \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Cancel Stream (sender only)

cast send <SABLIER_LOCKUP_ADDRESS> \
  "cancel(uint256)" \
  <STREAM_ID> \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Renounce Cancelability (sender only, irreversible)

cast send <SABLIER_LOCKUP_ADDRESS> \
  "renounce(uint256)" \
  <STREAM_ID> \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME>
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Check Streamed Amount

cast call <SABLIER_LOCKUP_ADDRESS> "streamedAmountOf(uint256)(uint128)" <STREAM_ID> --rpc-url <RPC_URL>

Get Recipient of Stream

cast call <SABLIER_LOCKUP_ADDRESS> "getRecipient(uint256)(address)" <STREAM_ID> --rpc-url <RPC_URL>

Using Forge Scripts (Alternative)

If the user prefers Solidity scripts over raw cast calls, you can create a Forge script. Reference the @sablier/lockup npm package.

Install dependency

forge init sablier-vesting && cd sablier-vesting
bun add @sablier/lockup

Example Forge Script

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.8.22;

import { Script } from "forge-std/Script.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { ISablierLockup } from "@sablier/lockup/src/interfaces/ISablierLockup.sol";
import { Lockup } from "@sablier/lockup/src/types/Lockup.sol";
import { LockupLinear } from "@sablier/lockup/src/types/LockupLinear.sol";

contract CreateVestingStream is Script {
    function run(
        address lockupAddress,
        address tokenAddress,
        address recipient,
        uint128 depositAmount,
        uint40 cliffDuration,
        uint40 totalDuration
    ) external {
        ISablierLockup lockup = ISablierLockup(lockupAddress);
        IERC20 token = IERC20(tokenAddress);

        vm.startBroadcast();

        // Approve Sablier to spend tokens
        token.approve(lockupAddress, depositAmount);

        // Build params
        Lockup.CreateWithDurations memory params;
        params.sender = msg.sender;
        params.recipient = recipient;
        params.depositAmount = depositAmount;
        params.token = token;
        params.cancelable = true;
        params.transferable = true;

        LockupLinear.UnlockAmounts memory unlockAmounts = LockupLinear.UnlockAmounts({ start: 0, cliff: 0 });
        LockupLinear.Durations memory durations = LockupLinear.Durations({
            cliff: cliffDuration,
            total: totalDuration
        });

        uint256 streamId = lockup.createWithDurationsLL(params, unlockAmounts, durations);

        vm.stopBroadcast();
    }
}

Run with:

forge script script/CreateVestingStream.s.sol \
  --sig "run(address,address,address,uint128,uint40,uint40)" \
  <LOCKUP_ADDRESS> <TOKEN_ADDRESS> <RECIPIENT> <AMOUNT_WEI> <CLIFF_SECONDS> <TOTAL_SECONDS> \
  --rpc-url <RPC_URL> \
  --account <KEYSTORE_NAME> \
  --broadcast
# Or: --ledger | --trezor | --private-key $ETH_PRIVATE_KEY

Important Notes

• Token decimals matter: Always convert human-readable amounts to wei (e.g., for 18-decimal tokens: amount * 1e18). Use cast --to-wei <amount> to convert.
• Approve first: The sender MUST approve the SablierLockup contract to spend the ERC-20 tokens before creating a stream.
• Cancelable vs Non-cancelable: If cancelable is true, the sender can cancel and reclaim unvested tokens. Set to false for trustless vesting.
• Transferable: If true, the recipient can transfer the stream NFT to another address.
• Gas costs: Linear streams are cheapest (~169k gas). Tranched streams cost more with more tranches (~300k for 4 tranches). Dynamic streams vary by segment count.
• Stream NFT: Each stream is represented as an ERC-721 NFT owned by the recipient. The NFT can be transferred if the stream is transferable.
• Minimum Solidity version: v0.8.22 for the Lockup contracts.
• Sablier UI: Streams can be viewed and managed at https://app.sablier.com

Quick Reference: Duration Conversions

Resources

• Docs: https://docs.sablier.com
• Lockup Source: https://github.com/sablier-labs/lockup
• Examples: https://github.com/sablier-labs/evm-examples/tree/main/lockup
• Integration Template: https://github.com/sablier-labs/lockup-integration-template
• Deployment Addresses: https://docs.sablier.com/guides/lockup/deployments
• Sablier App: https://app.sablier.com