Cancel all open orders
Cancels every open order for the authenticated wallet, optionally scoped to a single market. Operates on a snapshot of the orders open at request receipt — orders placed concurrently while the cancel runs are not guaranteed to be included; stop quoting before relying on a clean book. Rate limited at 1 req/sec per wallet — intended for operational wind-down, not per-order cleanup. No KYC / deposit-tier gating — cancellation is always permitted. Breaking change (2026-06): the response is now { cancelled: string[], notCancelled: {} } (previously { cancelled: number }). Read cancelled.length for the count; per-order failures that were previously dropped from the count now appear in notCancelled with a reason.
Authorizations
Partner / integrator key — format ps_live_<keyId>_<secret>. Issued by PredictStreet ops via the admin panel; never self-service. Never ship to a browser. multi_wallet partners must additionally send X-User-Wallet: 0x<40-hex> on every authenticated request to declare the acting wallet. See the API keys guide for scope taxonomy, partner kinds, rate limits, and rotation procedure.
Headers
Required for multi_wallet partners on every authenticated request; ignored for single_wallet. Declares the acting end-user wallet for this request — drives KYC checks, balances/positions/orders attribution, rate-limit buckets, and audit. Lower-cased server-side. Missing on a multi_wallet key → 401 api_key_user_wallet_required; malformed → 401 api_key_user_wallet_invalid. The on-chain CTFExchange/Vault contracts still verify EIP-712 signer ↔ vault binding, so loosening API-layer attribution is safe by construction.
^0x[a-fA-F0-9]{40}$"0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb3"
Body
Response
Ids of the orders that transitioned to CANCELLED. Breaking change (2026-06): this field was previously a count (number); it is now the array of cancelled order ids. Use cancelled.length for the count.
Map of orderId → reason for every snapshot order that was not cancelled. Same reason vocabulary as POST /api/orders/cancel-batch (not_found, already_terminal, lock_invariant, unknown). These per-order failures were previously dropped silently from the count.
Echoes the request scope when set.