Fee reserve

A covenant-tracked balance that pays network fees exactly, so agents don't need a separate wallet for gas.

A fee reserve is a portion of a vault's on-chain balance that the covenant tracks separately from the vault's principal (protected value) and uses exclusively to pay Kaspa network fees for the vault's own transactions. It exists so an agent can spend without needing a second, separately funded wallet just to cover transaction fees.

#How it is bounded

The covenant computes the actual network fee for a transaction from the transaction's own real inputs and outputs — it is not told the fee by the application and does not trust a claimed figure. Consumption of the fee reserve is bounded to the smaller of a configured per-transaction fee cap and the transaction's actual fee. This means the fee reserve can only ever become network fee: it can never be redirected as a payment to some other recipient, and it can never be drawn down as if it were spendable principal.

#Why this matters for autonomous agents

Without a covenant-tracked fee reserve, an autonomous agent (a bot or AI agent acting without a human present) would need a separately funded, separately managed wallet just to keep paying gas — a second thing that can run dry, be forgotten, or need topping up. A covenant-controlled fee reserve removes that operational burden: the vault itself funds its own transaction fees, under the same consensus-enforced accounting as everything else the covenant does.

#Topping up the reserve

The owner can top up a vault's fee reserve (separately from topping up its principal) at any time, through an owner-signed covenant operation, the same way they would top up the vault's balance.

#Per-agent fee caps

In covenant versions with multiple independent agents, each agent can have its own maximum fee-reserve consumption per transaction, so one agent's transaction fees are bounded independently of another's.

See also: Vault, Spending authority.