Use canonical asset identifiers
A ticker alone is not enough. Identify network, contract or issuer context, decimals, and lifecycle. Preserve base units and the original transaction identifier. Display conversions happen at the edge.
Pool API Architecture
Asset & Token Pool API
System boundaries for digital asset pools: canonical asset identifiers, wallets, accounts, double-entry ledgers, reservations, settlement, and custody controls.
What this pool coordinates
One policy boundary for shared capacity
Asset pools coordinate balances and operations across stablecoins, network tokens, tokenized assets, and internal settlement units. The architecture must distinguish an internal account balance from onchain ownership, a wallet address from a customer account, and a submitted transaction from final settlement. Those boundaries are the product, not implementation trivia.
Architecture priorities
Build the contract before the marketplace
Separate ledger and custody
The ledger attributes value to accounts. Wallet infrastructure controls or observes onchain assets. An omnibus wallet, segregated address, and self-custody integration have different risks and obligations. The API should state the model clearly.
Reserve before withdrawal
Validate authorization, destination, policy, and available balance, then create an atomic reservation. Approval, signing, submission, confirmation, and reconciliation are distinct states. Idempotency prevents a retry from creating a second transfer.
Reconcile continuously
Compare internal entries, wallet balances, provider statements, and chain observations. Differences become review cases, not silent balance edits. Late events, provider fees, reorganizations, unsupported assets, and decimal mistakes all need explicit handling.
Reference modules
The control-plane pieces
Use these modules as separate services or bounded components. Their contracts matter more than how many repositories contain them.
Reference module
Asset Registry
Network, contract, decimals, status, and operation policy.
Reference module
Double Entry
Balanced accounts, immutable entries, and compensating corrections.
Reference module
Wallet Boundary
Narrow signing services, scoped keys, and approval policy.
Reference module
Settlement
Observed, confirmed, available, submitted, finalized, and failed states.
Reference module
Webhooks
Signature verification, deduplication, ordering tolerance, and replay.
Reference module
Reconciliation
Ledger, wallet, provider, and network comparisons.
Conceptual request
A concrete API shape
This example is an architecture pattern, not a live PoolAPI.com endpoint. It shows explicit identifiers, units, limits, and idempotency rather than hidden defaults.
POST /withdrawal-requests
{
"asset_id": "usdc:network-example:contract-id",
"account_id": "acct_treasury",
"amount_base_units": "25000000",
"destination_id": "dest_approved_01",
"idempotency_key": "wd_01J..."
}Frequently asked questions
Common design decisions
Is an API balance proof of onchain custody?
No. The API should disclose how the internal account maps to wallets and who controls the keys.
Can all stablecoins share one asset code?
No. Preserve issuer, network, contract, decimals, and operational policy for each asset.
Why use double-entry accounting?
It makes every movement balanced and explainable, including fees, pending settlement, and corrections.
Does this site provide financial advice?
No. PoolAPI.com provides technical architecture guidance and is not financial, legal, tax, or investment advice.
Field notes
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