> ## Documentation Index > Fetch the complete documentation index at: https://docs.0xmonaco.com/llms.txt > Use this file to discover all available pages before exploring further. # Initiate withdrawal > Initiate a withdrawal. Master accounts with the withdraw permission only. Routes through the matching engine to debit the balance and allocate a `withdrawal_index`, then returns it plus the target vault address. The `calldata` field is empty: `executeWithdrawal` requires the merkle proof, which only exists after the withdrawal's root is confirmed on-chain. Poll GetWithdrawal to obtain the calldata once it is ready. ## OpenAPI ````yaml /proto-openapi/api/openapi.yaml post /api/v1/withdrawals openapi: 3.0.3 info: title: Monaco Protocol API description: REST API for the Monaco Protocol hybrid CLOB exchange. version: 1.0.0 servers: - url: https://staging.apimonaco.xyz description: Staging server (Testnet) security: [] tags: - name: AccountsService - name: ApplicationsService - name: AuthService - name: BuildercodeRewardsService - name: CopyTradingService - name: DelegatedAgentsService - name: FaucetService - name: FeesService - name: HealthService - name: ManagedMarketsService description: |- Wallet-authenticated maker assignments. The signed session must match both configured maker user and application. Owner IDs are process fences, never auth. Only wallet sessions are supported; delegated-agent sessions receive 403. - name: MarginAccountsService description: |- Current public isolated-margin semantics: - a user has one parent margin account per application scope - opening orders create or reuse isolated position buckets under that parent - parent account creation is handled internally by margin workflows - name: MarketService - name: OrderbookService - name: OrdersService - name: PositionsService description: |- Current public isolated-margin semantics: - positions link to a parent margin account and, when applicable, a bucket id - opening orders create or reuse isolated position buckets under the parent - users can open another isolated position by reusing the parent account with a different market bucket - name: PulseService - name: SweeperService - name: TraderCodeService - name: TradesService - name: WhitelistService - name: WithdrawalsService paths: /api/v1/withdrawals: post: tags: - WithdrawalsService - Withdrawals summary: Initiate withdrawal description: |- Initiate a withdrawal. Master accounts with the withdraw permission only. Routes through the matching engine to debit the balance and allocate a `withdrawal_index`, then returns it plus the target vault address. The `calldata` field is empty: `executeWithdrawal` requires the merkle proof, which only exists after the withdrawal's root is confirmed on-chain. Poll GetWithdrawal to obtain the calldata once it is ready. operationId: initiate_withdrawal requestBody: content: application/json: schema: $ref: '#/components/schemas/InitiateWithdrawalRequest' required: true responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/Withdrawal' '400': description: Invalid request (bad amount, address, or asset) '401': description: Authentication required '403': description: Caller lacks the withdraw permission '404': description: Asset not found '429': description: >- Movement rate limit exceeded — withdrawals and collateral transfers share a per-user budget; retry after the interval in details.retryAfter '500': description: Internal server error '503': description: Matching engine unavailable security: - monacoSignature: [] - monacoHttpSignature: [] components: schemas: InitiateWithdrawalRequest: type: object properties: assetId: example: 123e4567-e89b-12d3-a456-426614174000 type: string description: UUID of the asset to withdraw format: uuid nullable: true amount: example: '1000000000000000000' type: string description: >- Raw token amount in the smallest unit (e.g. wei) as a stringified positive integer nullable: true destination: example: '0x742d35cc6634c0532925a3b8d4060f31e2c3d8b5' type: string description: >- On-chain address that will receive the withdrawal (EVM, 42 chars including 0x) nullable: true source: example: spot type: string description: >- Source ledger to withdraw from: "spot" (default) debits spot balance; "margin" directly debits withdrawable collateral from the parent margin account nullable: true Withdrawal: type: object properties: withdrawalIndex: example: '42' type: string description: >- Allocated withdrawal index — matches executeWithdrawal.index on-chain nullable: true vaultAddress: example: '0x5fbdb2315678afecb367f032d93f642f64180aa3' type: string description: >- 0x-prefixed lowercase address of the vault contract the calldata is submitted to nullable: true calldata: type: string description: >- 0x-prefixed ABI-encoded executeWithdrawal(...) calldata; submit as tx.data to the vault. Empty on InitiateWithdrawal (the merkle proof is not available until the withdrawal root is confirmed on-chain) — fetch it from GetWithdrawal once ready nullable: true securitySchemes: monacoSignature: type: apiKey description: >- Ed25519 session-key request signing. Every authenticated request carries three headers: `X-Monaco-PublicKey` (64-char lowercase-hex session public key), `X-Monaco-Timestamp` (Unix milliseconds, within 30s of server time), and `X-Monaco-Signature` (hex ed25519 signature). The signature is over `METHOD\npath?query\ntimestamp_ms\nSHA256_hex(body)`, where the body hash is the SHA-256 of the empty byte string when there is no body. Obtain the session keypair from `POST /api/v1/auth/challenge` followed by `POST /api/v1/auth/verify`. name: X-Monaco-Signature in: header monacoHttpSignature: type: apiKey description: >- RFC 9421 Ed25519 session-key request signatures. Send Signature-Input, Signature, and Content-Digest together; never combine them with X-Monaco-* credentials. The monaco signature covers @method, @path, @query, and content-digest in that order, with created (Unix seconds within 30s of server time), keyid (registered lowercase-hex session public key), and alg=ed25519 parameters. Content-Digest uses RFC 9530 sha-256 over the exact body bytes, including the empty body. Query coverage retains ordering and percent encoding. Timestamp freshness does not reject repeated identical requests; use endpoint idempotency where supported. Existing legacy signing remains supported during server-first migration; SDK RFC 9421 signing is opt-in. See https://docs.0xmonaco.com/reference/http-message-signatures for the complete profile and trust model. name: Signature in: header ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.