Sablier Flow Stream Withdrawal

Overview

Withdraw available tokens from one or more Sablier Flow open-ended payment streams on the user's behalf. The skill discovers the user's streams through the Sablier indexer, lets the user pick any subset (default: all eligible), and executes one batch(bytes[]) transaction per SablierFlow contract on the selected chain.

Sablier Flow exposes two per-stream withdraw entrypoints (flow/src/interfaces/ISablierFlow.sol:497-531):

• withdraw(uint256 streamId, address to, uint128 amount) — explicit-amount withdrawal.
• withdrawMax(uint256 streamId, address to) returns (uint128) — drains the full currently-withdrawable balance.

Batching is provided by the inherited Batch.batch(bytes[]) payable (SablierFlow.sol:13,39; @sablier/evm-utils/src/Batch.sol). batch delegatecalls every entry against address(this), so msg.sender and msg.value are reused across all sub-calls. Each sub-call can target a different stream, amount, and to address. The batch is all-or-nothing: any sub-call revert bubbles up and reverts the whole transaction. There is no per-stream skip event analogous to Lockup's InvalidWithdrawalInWithdrawMultiple.

This skill charges no markup. The only fee paid is the on-chain protocol fee (calculateMinFeeWei) set by the comptroller; it may be 0. Because batch delegatecalls and reuses msg.value, the required msg.value is max(calculateMinFeeWei across the batch), not the sum.

This skill is a coordinator for Flow withdrawal and execution routing.

Arguments

Workflow

1. Confirm product fit

1. Verify the user wants to withdraw from existing Sablier Flow open-ended streams.

1. If the user wants to create a Flow stream instead, route to sablier-create-open-ended-stream. If that skill is unavailable, recommend installing it with:

``bash npx skills add sablier-labs/sablier-skills --skill sablier-create-open-ended-stream ``

1. If the user describes vesting, cliffs, tranches, or a fixed end date, route to sablier-withdraw-vesting. If that skill is unavailable, recommend installing it with:

``bash npx skills add sablier-labs/sablier-skills --skill sablier-withdraw-vesting ``

2. Check requested features

Stop and call out unsupported requests before selecting an execution path.

• Cross-chain batching is not supported. This skill batches across all eligible streams on a single chain per invocation. If the user has streams on multiple chains, run the skill again per chain.
• Default is withdrawMax for every selected stream — each selected stream is withdrawn at its full currently-available balance (withdrawableAmountOf). Partial withdrawals are an opt-in: ask the user to select a single stream and supply an amount, then the runbook routes that one stream through withdraw(uint256,address,uint128) instead of withdrawMax. The bulk path always drains the full available amount per stream.
• Access-control rule (single, no version dispatch) — msg.sender must be the stream's recipient (the NFT owner) or an ERC-721-approved third party, or to == recipient. The skill defaults to to = OWNER (the connected wallet) and only surfaces streams where the wallet is the recipient or has approval, so this rule is auto-satisfied. If a non-recipient caller wants to redirect tokens elsewhere, it cannot — Flow only allows a non-recipient caller when to == recipient (SablierFlow.sol:1001).
• Voided streams cannot withdraw. A Flow.Status.VOIDED stream is not eligible — the contract reverts on _withdraw. The runbook re-checks statusOf(streamId) != VOIDED for every selected stream right before broadcast because batch is all-or-nothing: a single voided stream taints the whole group. See [references/cli.md § Preflight Checks](references/cli.md#preflight-checks).
• Withdrawing native tokens (ETH, POL, etc.) is not supported. Sablier Flow streams only hold ERC-20 tokens. If the user mentions "ETH from my stream", they most likely mean WETH — confirm the token symbol before proceeding.
• Tokens with more than 18 decimals are not supported by Flow. This is a contract-level invariant; no eligible stream can exceed it.

3. Clarify the required inputs

Use the AskUserQuestion tool to fill any missing inputs. Ask only for what is missing — never re-ask for values the user already provided.

• Wallet address. A 0x-prefixed EVM address — case is not enforced; the runbook lowercases it before querying the indexer. This is the address that will sign the withdraw transactions. Ask for this first — both chain and token can be inferred from the indexer once the wallet is known.
• Chain name. Optional. If the user does not know which chain, do not send them to an external UI — query the Sablier Streams indexer for every non-voided Flow stream where the wallet is the recipient across all chains, collect the distinct chainId values, map them to chain names via the [Supported Chains](references/cli.md#supported-chains) table, and offer them as AskUserQuestion options. If exactly one chain has streams, auto-select it and tell the user. See [references/cli.md § Chain discovery](references/cli.md#chain-discovery).
• Token symbol. Optional. If the user does not know which token, query the indexer for every non-voided Flow stream on the resolved chain where the wallet is the recipient, and offer the distinct token symbols as AskUserQuestion options (see [references/cli.md § Stream discovery](references/cli.md#stream-discovery)).
• Withdrawal address (to). Optional. Default is the recipient itself. Flow lets the recipient (or an approved operator) redirect tokens to any address by passing a different to; non-recipient callers can only pass to == recipient. Only ask if the user explicitly mentions sending withdrawn tokens elsewhere.

Do not guess or silently apply defaults for these parameters. Only proceed once all inputs are confirmed.

4. Validate chain support

1. Check whether the resolved chain is listed in the [Supported Chains](references/cli.md#supported-chains) table in the execution runbook.
2. If a chain surfaced by the indexer is not in the table, check Sablier Flow deployments and ask the user for an RPC URL. If still unresolved, stop execution of this skill.

5. Route to execution

Hand off to [references/cli.md](references/cli.md) for stream discovery, multi-select, per-contract grouping, preview, confirmation, and per-group broadcast. The discovery step pipes the indexer response through [scripts/filter-withdrawable.sh](scripts/filter-withdrawable.sh), which batches withdrawableAmountOf across every candidate into a single Multicall3 call — this collapses N RPC round trips into one and avoids presenting the user streams with nothing currently available.

Resources

• Sablier Documentation
• EVM Flow Deployments
• Sablier Indexer API
• Sablier GraphQL Schema
• Sablier Indexers Repo
• Sablier Flow Monorepo
• Sablier Flow CHANGELOG

Support

If you encounter any issues or unexpected errors with this skill, please file an issue at sablier-labs/sablier-skills.