Aggregators let a buyer sweep multiple listings from several marketplaces in one transaction. The convenience rests on a contract that performs the individual trades on the buyer's behalf.
Listings live on separate contracts
Each marketplace maintains its own contracts, order formats and fee arrangements. A listing on one venue is not visible to the settlement logic of another.
Buying across three marketplaces normally means three separate transactions, three confirmations and three network fees. In a fast-moving collection, the delay between them is meaningful.
An aggregator solves this by acting as an intermediary that holds instructions for all three and executes them within a single call. The venues themselves need no awareness of it.
Off-chain orders make batching possible
Most marketplaces store listings as signed messages held off-chain rather than as on-chain records. A seller signs a statement of the terms, and that signature is stored by the platform.
Anyone holding a valid signed order can submit it for settlement. This is what allows an aggregator to collect orders from multiple sources and present them together.
The seller has not authorized the aggregator specifically. They authorized a set of terms, and the aggregator supplies a counterparty who accepts those terms.
Partial failure has to be handled deliberately
Between the moment an aggregator reads a listing and the moment the transaction confirms, an asset may be sold to someone else or withdrawn. Some orders in a batch will fail.
If the contract reverted the whole transaction on any single failure, large sweeps would rarely complete. Aggregators therefore allow individual purchases to fail while the rest proceed.
Unspent funds are returned within the same transaction. The buyer receives whatever remained available and pays only for those items.
Fee handling gets complicated
Each marketplace applies its own commission and its own treatment of creator royalties, and those policies differ. A batch spanning several venues carries several fee regimes at once.
The aggregator must compute the correct payment for each order and forward it to the right recipient. Errors here surface as failed transactions rather than as silent losses.
Displayed totals therefore include components the buyer never chose. Reading the breakdown before confirming is the only way to know what is being paid to whom.
Approvals concentrate risk
Using an aggregator requires granting its contract permission to move tokens and spend funds on your behalf. That permission persists until it is revoked.
A flaw in widely used routing code would therefore affect many wallets simultaneously, which is why these contracts attract heavy scrutiny and repeated auditing.
The practical consequence for users is that stale approvals accumulate quietly. Reviewing and clearing them periodically limits how much a future failure could reach.