> ## 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. # Create a subscription > Creates a delivery subscription for the authenticated tenant. The tenant is taken from the validated JWT claims only — a `tenant_id` in the body is ignored. A `webhook` subscription is born `active` and mints a signing secret that is returned exactly once in this response (see `signingSecret`). A queue subscription (`sqs`, `rabbitmq`, `eventbridge`) is born `pending_verification` and mints no secret; it stays undeliverable until an outbound credential is supplied and probed via `PUT /v1/subscriptions/{id}/credential`. Inline `sink_config` or `credential` at create is rejected — queue credentials arrive only on the credential PUT. ## OpenAPI ````yaml en/openapi/v3-current/streaming-hub.yaml post /v1/subscriptions openapi: 3.1.0 info: title: Lerian Streaming Hub API version: v1.0.0 contact: email: contact@lerian.studio name: Lerian Studio url: https://lerian.studio license: name: Lerian Studio General License description: >- The Streaming Hub control-plane API. Streaming Hub is Lerian's managed event-delivery edge: it consumes CloudEvents from the platform's internal streaming backbone and fans them out to a tenant's own external destinations — webhooks, Amazon SQS, RabbitMQ, Amazon EventBridge, or a pull inbox. This API lets a tenant browse the manifest-fed event catalog, create and manage delivery subscriptions, verify and rotate their credentials, read delivery health, and pull entitled events. Errors use a flat `{"error":""}` envelope (a low-cardinality, machine-readable token — never RFC 9457 problem+json). Mutating operations require an `X-Idempotency` header for at-most-once semantics; a replayed request returns the original response byte-for-byte with `X-Idempotency-Replayed: true`. The catalog and the pull events surface are tenant-scoped through the bearer JWT; the operational probe endpoints (`/healthz`, `/readyz`, `/version`, `/runtime`, `/metrics`) are unauthenticated. Streaming Hub is closed source under the Lerian Studio General License. servers: - url: https://streaming-hub.sandbox.lerian.net security: - BearerAuth: [] tags: - name: Catalog description: Browse the manifest-fed catalog of event types available for subscription. - name: Subscriptions description: >- Create, read, update, and delete delivery subscriptions, and drive the destination verification lifecycle (ping, verify, credential, delegated grant, secret rotation, health). - name: Event Delivery description: >- Pull entitled events for a pull-sink subscription (cursor-as-acknowledgment read). - name: Admin description: Cross-tenant operator forensics. Requires an operator authorization scope. - name: Operational description: Unauthenticated liveness, readiness, build, runtime, and metrics probes. paths: /v1/subscriptions: post: tags: - Subscriptions summary: Create a subscription description: >- Creates a delivery subscription for the authenticated tenant. The tenant is taken from the validated JWT claims only — a `tenant_id` in the body is ignored. A `webhook` subscription is born `active` and mints a signing secret that is returned exactly once in this response (see `signingSecret`). A queue subscription (`sqs`, `rabbitmq`, `eventbridge`) is born `pending_verification` and mints no secret; it stays undeliverable until an outbound credential is supplied and probed via `PUT /v1/subscriptions/{id}/credential`. Inline `sink_config` or `credential` at create is rejected — queue credentials arrive only on the credential PUT. operationId: createSubscription parameters: - $ref: '#/components/parameters/IdempotencyKey' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateSubscriptionRequest' responses: '201': description: >- The subscription was created. `signingSecret` is present only for a `webhook` sink and is shown exactly once — save it on receipt, it cannot be retrieved later, only rotated. headers: X-Idempotency-Replayed: $ref: '#/components/headers/IdempotencyReplayed' content: application/json: schema: $ref: '#/components/schemas/CreateSubscriptionResponse' '400': $ref: '#/components/responses/BadRequestOrMissingIdempotency' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '409': $ref: '#/components/responses/IdempotencyConflict' '422': description: >- The request is caller-correctable. `error` is one of `validation_error` (bad `sink_kind`, invalid endpoint / schema / event_types), `inline_sink_config_forbidden` (an inline `sink_config` / `credential` was sent), or `endpoint_blocked` (the webhook endpoint resolved to a blocked, private, or metadata address). content: application/json: schema: $ref: '#/components/schemas/Error' '500': $ref: '#/components/responses/InternalError' security: - BearerAuth: [] components: parameters: IdempotencyKey: name: X-Idempotency in: header required: true description: >- A client-chosen unique key that makes this mutation at-most-once. A mutation sent without it is rejected before any write with `400 missing_idempotency_key`. Reusing the same key with an identical request replays the original response byte-for-byte (with `X-Idempotency-Replayed: true`); reusing it with a different request body returns `409 idempotency_conflict`. To re-drive a corrected request, mint a new key. schema: type: string schemas: CreateSubscriptionRequest: type: object description: >- The create body. It carries no `tenant_id` (the tenant is resolved from the JWT). Inline `sink_config` / `credential` fields are rejected with `422 inline_sink_config_forbidden` — queue credentials arrive only via the credential PUT. properties: name: type: string description: >- A human label for the subscription. Required and non-blank (whitespace-only is rejected). examples: - orders-webhook sink_kind: $ref: '#/components/schemas/SinkKind' endpoint: type: string description: >- The destination address, interpreted per sink kind. For `webhook`, an `https://` URL with no embedded userinfo. For `pull`, omit it — the server synthesizes a `pull://` value. For `sqs`, the `https://` queue URL. For `rabbitmq`, an `"/"` string (exchange required, routing key optional). For `eventbridge`, the event-bus name / detail-type addressing string. The broker host or AWS region for queue kinds lives in the encrypted credential, not here. examples: - https://hooks.example.com/lerian event_types: type: array description: >- The event types to deliver. Validated softly against the catalog — an unknown type warns but never blocks onboarding. items: type: string examples: - - transaction.created schema_major: type: integer description: >- Optional schema-major pin. When set, delivery follows the versioned topic for that major; when omitted, the subscription follows the base topic. examples: - 1 plan_tier: type: string description: The plan tier for the subscription. examples: - standard required: - name - sink_kind CreateSubscriptionResponse: type: object additionalProperties: false description: >- The create response. `signingSecret` is present only for a `webhook` sink and is shown exactly once; it is stored only as ciphertext and is never returned by any read path. properties: subscription: $ref: '#/components/schemas/Subscription' signingSecret: type: string description: >- The one-time webhook signing secret (write-only). Minted server-side, returned exactly once here, and never retrievable later — only rotated. Absent for non-webhook sinks. examples: - whsec_9f8c2b1e4a7d6055c3e2f10987ab4c21 required: - subscription Error: type: object additionalProperties: false description: >- The flat error envelope used across the `/v1` and `/admin` surfaces. It carries a single low-cardinality, machine-readable token and never leaks secret material or internal detail. (A `403` from the authorization decision point is the one exception — its body is plain text.) properties: error: type: string description: The machine-readable error token. examples: - not_found required: - error SinkKind: type: string description: >- The delivery destination kind. `webhook` posts signed HTTPS requests; `pull` exposes an inbox read over `GET /v1/events`; `sqs`, `rabbitmq`, and `eventbridge` fan out to the named queue or bus. enum: - webhook - pull - sqs - rabbitmq - eventbridge Subscription: type: object additionalProperties: false description: >- The non-secret projection of a subscription. It never carries the signing secret or any credential material. properties: id: type: string format: uuid description: The unique identifier of the subscription (UUIDv7). examples: - 0192f1a0-0000-7000-8000-00000000c001 name: type: string description: The human label supplied at create. examples: - orders-webhook sink_kind: $ref: '#/components/schemas/SinkKind' endpoint: type: string description: The destination address (per sink kind). examples: - https://hooks.example.com/ingest event_types: type: array description: >- The event types the subscription delivers. Omitted when none are pinned. items: type: string examples: - - account.created - account.updated schema_major: type: integer description: >- The pinned schema major, when set. Omitted when the subscription follows the base topic. examples: - 2 signature_version: type: integer description: The webhook signature scheme version. examples: - 1 plan_tier: type: string description: The subscription's plan tier. examples: - standard enabled: type: boolean description: >- The operator on/off flag. Independent of `verification_state`; both must hold for delivery. examples: - true verification_state: $ref: '#/components/schemas/VerificationState' created_at: type: string format: date-time description: Creation timestamp (UTC, RFC 3339). examples: - '2026-01-15T12:00:00Z' updated_at: type: string format: date-time description: Last-update timestamp (UTC, RFC 3339). examples: - '2026-01-15T12:00:00Z' required: - id - name - sink_kind - endpoint - signature_version - plan_tier - enabled - verification_state - created_at - updated_at VerificationState: type: string description: >- The subscription's position in the destination verification state machine. Only an `active` subscription is deliverable. A `webhook` sub is born `active`; a queue sub is born `pending_verification` and reaches `active` on a successful credential probe. `degraded` and `disabled` signal an impaired or auto-disabled destination that a successful `verify` returns to `active`. enum: - pending_verification - active - degraded - disabled headers: IdempotencyReplayed: description: >- Present and set to `true` when this response is a replay of a previously committed request carrying the same `X-Idempotency` key (the handler did not run again). schema: type: string enum: - 'true' responses: BadRequestOrMissingIdempotency: description: >- The request body is malformed (`bad_request`) or the required `X-Idempotency` header is missing (`missing_idempotency_key`, rejected before any write). content: application/json: schema: $ref: '#/components/schemas/Error' Unauthorized: description: >- Authentication failed, or there is no trusted tenant context. `error` is `unauthorized` (uniform body — no reason is leaked). content: application/json: schema: $ref: '#/components/schemas/Error' Forbidden: description: >- The authorization decision point denied the request. The body is plain text (not the JSON error envelope). content: text/plain: schema: type: string IdempotencyConflict: description: >- An in-flight duplicate, or the same `X-Idempotency` key was reused with a different request fingerprint — `error` is `idempotency_conflict`. content: application/json: schema: $ref: '#/components/schemas/Error' InternalError: description: >- An infrastructure fault. `error` is `internal_error` (sanitized; detail is logged, never returned). content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- A bearer JWT issued by plugin-auth (lib-auth). The tenant identity is resolved from the validated token claims; the `/v1` surface never reads a tenant from the body, path, or query. Machine callers obtain a token via the plugin-auth client-credentials flow. The `/admin` surface authorizes against an operator scope and carries no tenant context. ````