> ## Documentation Index > Fetch the complete documentation index at: https://docs.lerian.studio/llms.txt > Use this file to discover all available pages before exploring further. # Compose and send a curated STR message > Catalog-gated, maker-checker-routed, per-type curated message-compose surface. The chosen capabilityId must be in the compose allowlist (STR0004/STR0005/STR0006/STR0007/STR0008/STR0053), resolve in the catalog, and be PUBLICLY_SUBMITTABLE; otherwise the request is rejected SPB-0003 (HTTP 400). The message is built through the shared compose pipeline and inherits the alçada emission gate: an amount above its band parks in PENDING_APPROVAL (visible in GET /v1/str/emission-approvals, emissionApprovalId set) and dispatches on quorum; below band it is SUBMITTED. Idempotent — replaying the same X-Idempotency key returns the same emission. The declared amount is forwarded verbatim; no position is summed. ## OpenAPI ````yaml en/openapi/v3-current/spb.yaml post /v1/str/messages/compose openapi: 3.1.0 info: contact: email: contact@lerian.studio name: Lerian Studio url: https://lerian.studio description: >- OpenAPI 3.1 surface for Lerian SPB, the direct integration between the institution and the Brazilian Payment System (SPB) over the National Financial System Network (RSFN). It covers the Reserve Transfer System (STR): message registry and capability catalog, operation lifecycle (bank transfers, IBS repasses, liquidity transfers, returns and cancellations), reserve-account and schedule queries, alçada governance, reconciliation, and event delivery. license: name: Lerian Studio General License title: Lerian SPB API version: 1.0.0 servers: - url: https://spb.sandbox.lerian.net security: [] tags: - description: Immutable audit-record trails for STR operations and lifecycle events. name: Audit - description: >- STR capability catalog describing supported message types and their constraints. name: Capabilities - description: >- ICP-Brasil certificate inventory with hot-reloadable rotation and activation. name: Certificates - description: >- Maker-checker approval queue for emissions parked above their alçada band: list pending, sign (approve), and deny. name: EmissionApprovals - description: Webhook event-delivery records with retry control for failed dispatches. name: EventDeliveries - description: Operation event catalog enumerating the emitted domain event types. name: Events - description: >- Inbound GEN-family notice log (GEN0001 connectivity echo, GEN0004 transmission error, GEN0005 administrative notice). name: GenNotices - description: >- SPB alçada governance: the value-band table and per-message-type signature requirements, hot-reloaded at runtime. name: Governance - description: >- Read raw STR message status: list messages and read a single message by NUOp. name: Messages - description: Aggregated operational summaries and metrics across STR operations. name: OperationalIntelligence - description: >- STR operation lifecycle for bank transfers and IBS repasses, including returns and cancellations. name: Operations - description: >- Service readiness state covering startup self-probes and dependency health. name: Readiness - description: Reconciliation cases and the actions that resolve operation discrepancies. name: Reconciliation - description: >- STR reports suite: synchronous, date-ranged aggregate reports (financial movement, rejected transactions, volumetria) over Lerian SPB's own transmission record. name: Reports - description: >- STR0013 reserve-account balance and STR0014 statement (extrato, message-mode) queries and their async results. name: ReserveQueries - description: >- GEN0019 participant responsável roster: full-replacement updates announced to BACEN. name: Responsibles - description: STR operating-window schedule governing when operations may be sent. name: Schedule - description: >- STR0001 single-party schedule queries (consulta de horários do STR) and their async STR0001R1 grid results. name: ScheduleQueries - description: Runtime SPB configuration settings for the STR integration. name: Settings - description: Webhook endpoint registration and management for event delivery. name: Webhooks - description: >- Flow (mandatory order): certificate → readiness → connectivity-test → submit. Activate a certificate, confirm the rail reports ready, pass a connectivity test, then submit an operation. Each step is its own resource; a submit must not be attempted before readiness passes. name: onboarding - description: >- Flow (mandatory order): parent operation SETTLED → return/cancel. A return or cancellation is a sub-resource of a settled parent operation; the {operationId}/{endToEndID} path segment enforces the parent structurally. name: lifecycle paths: /v1/str/messages/compose: post: tags: - Messages summary: Compose and send a curated STR message description: >- Catalog-gated, maker-checker-routed, per-type curated message-compose surface. The chosen capabilityId must be in the compose allowlist (STR0004/STR0005/STR0006/STR0007/STR0008/STR0053), resolve in the catalog, and be PUBLICLY_SUBMITTABLE; otherwise the request is rejected SPB-0003 (HTTP 400). The message is built through the shared compose pipeline and inherits the alçada emission gate: an amount above its band parks in PENDING_APPROVAL (visible in GET /v1/str/emission-approvals, emissionApprovalId set) and dispatches on quorum; below band it is SUBMITTED. Idempotent — replaying the same X-Idempotency key returns the same emission. The declared amount is forwarded verbatim; no position is summed. operationId: composeStrMessage parameters: - description: >- Bearer JWT token (the maker subject is derived from it for the alçada gate). in: header name: Authorization schema: description: >- Bearer JWT token (the maker subject is derived from it for the alçada gate). type: string - description: Idempotency key (canonical; legacy alias X-Idempotency-Key). in: header name: X-Idempotency schema: description: Idempotency key (canonical; legacy alias X-Idempotency-Key). type: string - description: Idempotency key (legacy alias). in: header name: X-Idempotency-Key schema: description: Idempotency key (legacy alias). type: string - description: Idempotency key TTL in seconds. in: header name: X-TTL schema: description: Idempotency key TTL in seconds. type: string requestBody: content: application/json: schema: $ref: '#/components/schemas/ComposeMessageRequest' responses: '202': content: application/json: schema: $ref: '#/components/schemas/ComposeMessageResponse' description: Accepted default: content: application/problem+json: schema: $ref: '#/components/schemas/Detail' description: Error security: - BearerAuth: [] components: schemas: ComposeMessageRequest: additionalProperties: false properties: amount: description: >- Transfer amount as a decimal string in BRL, minor-unit precision (two decimal places). Forwarded VERBATIM into the submit DTO and the alçada gate — Lerian SPB performs NO arithmetic on it. examples: - '150000.00' pattern: ^[0-9]+(\.[0-9]+)?$ type: string capabilityId: description: >- STR capability code to compose. Must resolve in the catalog, be PUBLICLY_SUBMITTABLE, and be in the compose allowlist (STR0004/STR0005/STR0006/STR0007/STR0008/STR0053). examples: - STR0008 type: string description: description: >- Optional free-text description; mandatory when purposeCode or finlddCli is 99999 (RSTR0034). Serialized into the STR Hist element. examples: - Wire transfer for invoice 2026-Q2-A47 type: string finlddCli: description: >- Optional client-level purpose code (5 digits) carried on STR0004/STR0008. When 99999 the description is required (RSTR0034). examples: - '00001' pattern: ^[0-9]{5}$ type: string metadata: additionalProperties: {} description: >- Opaque client-side metadata forwarded verbatim to the submit DTO (NOT sent to BACEN). Do not include sensitive fields. type: object purposeCode: description: >- BACEN STR purpose code (finalidade), exactly 5 digits. When 99999 (Outros) a description is mandatory (RSTR0034). examples: - '00001' pattern: ^[0-9]{5}$ type: string recipient: $ref: '#/components/schemas/ComposeParticipantAccount' description: Crediting (creditor) participant account receiving the transfer. sender: $ref: '#/components/schemas/ComposeParticipantAccount' description: Debiting (debtor) participant account originating the transfer. required: - capabilityId - sender - recipient - amount - purposeCode type: object ComposeMessageResponse: additionalProperties: false properties: controlNumber: description: >- 14-digit STR control number identifying the message on the SPB network. examples: - '20260621000001' type: string correlationId: description: >- Request-scoped correlation identifier echoing X-Request-ID, for pivoting from response to trace. examples: - req-7a3f9c2e type: string emissionApprovalId: description: >- Set ONLY when the emission parked: the maker-checker queue id (equal to messageId). Poll GET /v1/str/emission-approvals to track it. Empty when SUBMITTED immediately. examples: - 6f2c8a1e-... type: string messageId: description: >- Internal outbound-message id assigned at persistence time; the key for the approval queue when parked. examples: - 6f2c8a1e-... type: string nuOp: description: >- 23-digit STR operation number stamped on the composed message (protocol correlation). examples: - '12345678202606210000001' type: string requiredSignatures: description: >- N-of-M distinct-actor quorum the parked emission must collect (the alçada band requirement). Omitted/0 when SUBMITTED immediately. examples: - 2 format: int64 type: integer status: description: >- Emission status: SUBMITTED (dispatched / liquidatable) or PENDING_APPROVAL (parked awaiting maker-checker quorum). examples: - PENDING_APPROVAL type: string required: - messageId - status - nuOp - controlNumber - correlationId type: object Detail: additionalProperties: false properties: code: description: >- Stable, machine-readable domain error code scoped to the emitting service (format: -NNNN). examples: - ERR-0001 type: string detail: description: >- A human-readable explanation specific to this occurrence of the problem. examples: - Property foo is required but is missing. type: string errors: description: Optional list of individual error details items: $ref: '#/components/schemas/ErrorDetail' type: - array - 'null' instance: description: >- A URI reference that identifies the specific occurrence of the problem. examples: - https://example.com/error-log/abc123 format: uri type: string status: description: HTTP status code examples: - 400 format: int64 type: integer title: description: >- A short, human-readable summary of the problem type. This value should not change between occurrences of the error. examples: - Bad Request type: string type: default: about:blank description: A URI reference to human-readable documentation for the error. examples: - https://example.com/errors/example format: uri type: string type: object ComposeParticipantAccount: additionalProperties: false properties: account: description: Optional traditional bank account number. examples: - '123456' type: string accountType: description: >- Optional account type: CC (checking/conta corrente) or PP (payment account/conta de pagamento). examples: - CC type: string branch: description: Optional bank branch (agência) number. examples: - '0001' type: string document: description: >- Holder document (CPF/CNPJ, digits only). Carried on the client codes STR0007/STR0008. examples: - '12345678901' type: string ispb: description: Participant ISPB, the 8-digit BACEN institution identifier. examples: - '12345678' maxLength: 8 minLength: 8 pattern: ^[0-9]{8}$ type: string name: description: Holder name. Carried on the client codes STR0007/STR0008. examples: - João da Silva type: string paymentAccount: description: >- Optional payment account identifier (conta de pagamento). Required when accountType is PP. examples: - '00000000123456' type: string required: - ispb type: object ErrorDetail: additionalProperties: false properties: location: description: >- Where the error occurred, e.g. 'body.items[3].tags' or 'path.thing-id' type: string message: description: Error message text type: string value: description: The value at the given location type: object securitySchemes: BearerAuth: bearerFormat: JWT description: JWT bearer token issued by the identity provider. scheme: bearer type: http ````