# Coin Control

Pick the outputs you spend — consolidation, fee strategy and separation, decided rather than
defaulted.

On a UTXO chain a balance is a collection of discrete unspent outputs, and which ones a transfer
consumes decides what it costs and what it commingles. The UTXO transfer flow lets an operator
select those inputs deliberately instead of deferring to automatic coin selection — inside the
same MPC signing and the same approval rules as every other transfer.

## Why automatic selection is not enough

Bitcoin fees scale with transaction size and every input adds size, so a transfer consuming fifty
small outputs costs far more than one consuming two.

- **Fees you can plan** — choosing the inputs is choosing the fee, and consolidating in a quiet
  fee window becomes a decision rather than an accident.
- **Dust that stops compounding** — deliberate consolidation combines many small outputs into
  fewer large ones, before the fragmentation tax is charged.
- **Separation held on-chain** — operational float kept apart from reserves, and earmarked outputs
  spent on purpose, rather than tracked only in a spreadsheet.

## Output-level construction, inside the governance

Operators work at the unspent-output level: selecting which outputs to spend, consolidating
fragmented balances, and constructing the transaction deliberately.

- Select the inputs, or consolidate many outputs into fewer.
- Signed by the same MPC committee — no single party, Vaultody included, can move funds alone.
- The same approval chains and role-based policies as any other transfer.
- Available from the dashboard and via the API.

## Specification

- **Asset model** — UTXO-based assets: Bitcoin and other UTXO chains, Litecoin among them.
- **Input selection** — choose the unspent outputs a transfer consumes, instead of deferring to
  automatic coin selection.
- **Consolidation** — combine many small outputs into fewer large ones, in a fee window you choose.
- **Evidence** — the transfer carries the usual per-state audit record, so which outputs funded it
  is on the record.
- **Account-based chains** — not applicable: an account-based address holds a single balance, so
  there are no outputs to select.

## FAQ

**Which assets have coin control?**
UTXO-based assets — Bitcoin and other UTXO chains, Litecoin among them. Account-based chains debit
a single balance, so there is nothing to select.

**Does selecting inputs step around our approval rules?**
No. A UTXO transfer is signed by the same MPC committee and clears the same approval chains and
role-based policies as any other transfer.

## Related

- [Mass Payouts](/features/mass-payouts)
- [Policy Engine](/features/policy-engine)
- [Audit Trail](/features/audit-trail)
- [Dashboard + API](/features/dashboard-and-api)