> ## 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. # Relay a cross-core TED return > The body crosses byte-verbatim to {address}/v1/cross-core/ted/returns at the owner's TED address, with the Courier's credential there, Content-Type, Chave-Idempotencia when sent, and X-Courier-Origin-Engine, the caller's engine id read from its credential. One attempt, inside 15 s; the payer resends the identical bytes while the outcome is unknown. ## OpenAPI ````yaml /en/openapi/v3-current/jd-courier.yaml post /v1/cross-core/ted/returns openapi: 3.1.0 info: contact: email: support@lerian.studio name: Lerian Studio Support description: >- The JD Courier API. Operators use it to manage the engines, the ownership map, the rails and their delivery modes, the retained messages, the SPB send journal and reconciliation. Engines use it to resolve and claim ownership, declare their Pix Automático payment legs, and relay a payment between two cores of the same institution to the core that owns the payee account. license: name: Lerian Studio General License title: JD Courier API version: v1.0.0 servers: [] security: - BearerAuth: [] tags: - description: >- The engine registry: the cores that consume the JD channel through the Courier, each with its participant set name: Engines - description: 'The ownership map: which engine owns each key. Every change is audited.' name: ownership - description: >- The rails: what each declares about itself, its activation and state per tenant, and its delivery modes name: channels - description: >- The engines' side of the ownership map: resolution for the on-us gate, authoritative and never advisory, the claim of the accounts, charger documents and Pix Automático recurrences the engine holds, and the declaration of a payment leg it holds. name: ownership-query - description: >- A same-bank Pix or TED between two cores: the Courier asks the map who owns the payee account, forwards the body byte for byte to that engine's address for the rail, and relays its answer. It stores, retries and posts nothing; bodies are not modelled. name: cross-core - description: >- The durable message store: redelivery on demand, without asking the vendor again name: ledger - description: >- Count reconciliation per rail: E(m) = C(m) + T(m) + R(m), the sequence gaps it saw, and the sends whose return leg never arrived name: assurance - description: >- The SPB send journal: every send, written before it leaves, and the sends whose outcome is unknown. A by-hand close records an operator's finding and never resends. name: send-journal - description: >- Per-(tenant, channel) state an operator acts on: lifting a durable channel halt name: channel-leases - description: >- Messages the Courier holds because no engine could receive them. A routing or delivery retention leaves by itself once its cause lifts, or when an operator asks for its routing decision to be run again. name: retained paths: /v1/cross-core/ted/returns: post: tags: - cross-core summary: Relay a cross-core TED return description: >- The body crosses byte-verbatim to {address}/v1/cross-core/ted/returns at the owner's TED address, with the Courier's credential there, Content-Type, Chave-Idempotencia when sent, and X-Courier-Origin-Engine, the caller's engine id read from its credential. One attempt, inside 15 s; the payer resends the identical bytes while the outcome is unknown. operationId: crossCoreTedReturns parameters: - description: >- The engine id the payer's own map lookup returned for the payee account. in: header name: X-Courier-Expected-Owner required: true schema: type: string - description: The payee's idempotency key, forwarded as sent. in: header name: Chave-Idempotencia schema: type: string requestBody: content: application/json: schema: type: object required: true responses: '400': description: >- JDC-0001, not-sent: the body is not a UTF-8 JSON object, or X-Courier-Expected-Owner is missing. '401': description: >- JDC-0401, no marker: the credential is not an enabled engine's granted cross-core:send. Nothing was sent. '409': description: >- Not-sent. JDC-0118: no engine owns the payee account. JDC-0119: the owner is not X-Courier-Expected-Owner; it moved, and after an earlier unknown attempt the payer parks the item. JDC-0121: the owner is the caller itself. '422': description: >- JDC-0104, not-sent: the payee account cannot be read from the body: its account, and its branch unless it is a payment account. '503': description: >- Not-sent. JDC-9001: the map or the registry is not readable. JDC-0120: the owner is disabled, declares no address for the rail, could not be reached, redirected or refused the Courier's credential. JDC-0902: the licence is revoked. A call whose request reached the payee and whose answer did not come back within 15 s gets no status at all: its connection is closed. default: description: >- The payee engine's answer, status, Content-Type and body as it wrote them, with no X-Send-Outcome: it reached the engine the map names. A payee that redirects or refuses the Courier's credential never took the call, and is the Courier's 503 JDC-0120 instead. security: - engineCredentials: - cross-core:send components: securitySchemes: BearerAuth: bearerFormat: JWT description: JWT bearer token issued by the identity provider. scheme: bearer type: http engineCredentials: description: >- An Access Manager application token whose subject is bound to exactly one engine; an engine may hold several, one per calling product. It reaches only the operations its scopes name; the operator surface refuses it. flows: clientCredentials: scopes: cross-core:send: Send a same-bank payment to the core that owns the payee account ownership:read: Read the ownership map ownership:write: >- Claim accounts, charger documents or a Pix Automático recurrence, or declare a Pix Automático payment leg, for the calling engine alone tokenUrl: https://access-manager.example.com/v1/login/oauth/access_token type: oauth2 ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.