> ## Documentation Index > Fetch the complete documentation index at: https://docs.osvi.ai/llms.txt > Use this file to discover all available pages before exploring further. # Send Message (Async) > Accepts an inbound customer message and answers immediately without waiting for the agent's reply. Every reply — and the turn's completion — is delivered to the agent's [delivery URL](/api-reference/endpoint/chat/delivery_webhook) instead of riding back on this response. Requires the agent to have a delivery URL configured; use this endpoint when your integration can't hold a request open for the length of a turn (e.g. a webhook-based gateway with its own timeout). Otherwise, [Send Message](/api-reference/endpoint/chat/send_message) is simpler. Takes the same parameters as [Send Message](/api-reference/endpoint/chat/send_message), including `idempotency_key`, interactive-message fields, and `supported_interactions`. ## OpenAPI ````yaml POST /v1/chat/inbound/async openapi: 3.1.0 info: title: OSVI AI API description: REST API for the OSVI AI voice and chat platform license: name: MIT version: 1.0.0 servers: - url: https://api.osvi.ai security: - ApiToken: [] paths: /v1/chat/inbound/async: post: summary: Send a chat message (async) description: >- Accepts an inbound customer message and answers immediately without waiting for the agent's reply. Every reply — and the turn's completion — is delivered to the agent's [delivery URL](/api-reference/endpoint/chat/delivery_webhook) instead of riding back on this response. Requires the agent to have a delivery URL configured; use this endpoint when your integration can't hold a request open for the length of a turn (e.g. a webhook-based gateway with its own timeout). Otherwise, [Send Message](/api-reference/endpoint/chat/send_message) is simpler. Takes the same parameters as [Send Message](/api-reference/endpoint/chat/send_message), including `idempotency_key`, interactive-message fields, and `supported_interactions`. requestBody: required: true content: application/json: schema: type: object required: - agent_uuid - customer_id properties: agent_uuid: type: string description: Unique identifier of the agent handling the conversation. example: agent_IsZ3Q6Sf_60Eh26XQMGbz-R_og customer_id: type: string description: >- Your identifier for the customer sending the message. Used to resolve the active session when `session_id` is omitted. example: '+15551112222' content: type: string description: >- The customer's message text. Required unless `type` is `interaction_response`. example: Hi, I need help. session_id: type: string description: >- Optional session UUID to route the message to. If omitted, the engine resolves the active/new session for the customer + agent. example: 4718a326-417b-4dda-90d0-21fd65a11cb8 idempotency_key: type: string description: >- Your identifier for this exact turn. Strongly recommended on this endpoint: since the reply arrives later on the delivery webhook, this is what lets you correlate it back to the request that triggered it (it's echoed on every delivered envelope). A retry with the same key returns the original `202` instead of accepting the turn twice. Can also be sent as an `Idempotency-Key` header instead of a body field. example: wh-2f8a1c-attempt-1 input_fields: type: object additionalProperties: true description: >- Arbitrary key-value object made available to the agent at runtime. Only applied when this request creates a new session. example: first_name: Alex state_fields: type: object additionalProperties: true description: >- Initial values for the agent's configured state fields. Only applied when this request creates a new session. example: {} context: type: array items: type: string description: >- Free-text context entries for a newly created session. Only the most recent 5 non-empty strings are retained. Only applied when this request creates a new session. example: - Customer called in about a refund yesterday. type: type: string enum: - message - interaction_response default: message description: >- `message` for a normal text message (default). `interaction_response` to answer an interactive message the agent sent — see [Interactive messages](/api-reference/endpoint/chat/interactive_messages). example: message interaction_id: type: string format: uuid description: Required when `type` is `interaction_response`. example: b6a3e6c2-2d61-4a4b-9c9a-5a2d9f6a2b10 option_id: type: string description: >- Shorthand answer for a simple option tap. Send this or `response`, not both. example: opt_confirm response: type: object description: >- Structured answer to a pending interactive message. Send this or `option_id`, never both. See [Interactive messages](/api-reference/endpoint/chat/interactive_messages). properties: kind: type: string enum: - selection - text - date - date_range example: selection value: description: >- A string for `selection`/`text`/`date`. An object `{start_date, end_date}` for `date_range`. example: opt_confirm supported_interactions: type: array description: >- Declares which interactive message types your client can render. See [Interactive messages](/api-reference/endpoint/chat/interactive_messages). items: type: object properties: tool_type: type: string enum: - ui_buttons - ui_carousel - ui_date_picker example: ui_buttons schema_version: type: integer example: 2 responses: '202': description: >- Turn accepted. The reply (and every other reply this turn produces) is delivered to the [chat delivery webhook](/api-reference/endpoint/chat/delivery_webhook), not in this response. content: application/json: schema: type: object properties: success: type: boolean example: true accepted: type: boolean example: true data: type: object properties: state: type: string enum: - accepted example: accepted turn_id: type: string description: >- Identifies this turn. Matches `turn_id` on every envelope the delivery webhook sends for it. example: turn_9f3d2a1b session_id: type: string example: 4718a326-417b-4dda-90d0-21fd65a11cb8 idempotency_key: type: string nullable: true description: >- Echoes the key you sent, or a server-generated one if you didn't send one. example: wh-2f8a1c-attempt-1 '400': description: >- A required parameter is missing — `agent_uuid`/`customer_id` always, `content` unless `type` is `interaction_response`, or `interaction_id`/(`option_id` or `response`) when it is. content: application/json: schema: $ref: '#/components/schemas/ChatV1Error' '401': description: Invalid or missing API token content: application/json: schema: $ref: '#/components/schemas/ChatV1Error' '404': description: >- The agent does not exist or is not associated with the authenticated account (`agent_not_found`). content: application/json: schema: $ref: '#/components/schemas/ChatV1Error' '409': description: >- An idempotency conflict: `idempotency_key_reused` (the same key was already used with different content), or `idempotency_key_mode_conflict` / `idempotency_key_rail_conflict` (the key was already accepted on the synchronous endpoint or over the WebSocket). content: application/json: schema: $ref: '#/components/schemas/ChatV1TurnError' '422': description: >- The agent is archived (`agent_archived`), not active (`agent_inactive`), or has **no delivery URL configured** (`delivery_url_required`) — this endpoint refuses every turn for an agent that has nowhere to deliver the reply. Also returned when a `response` on an `interaction_response` fails validation (a `selection` not among the message's options/items, or a value the message doesn't allow). content: application/json: schema: $ref: '#/components/schemas/ChatV1TurnError' '502': description: >- The chat engine could not be reached, or returned an error other than the ones listed above — including an overloaded engine, which surfaces here rather than as a `503`. content: application/json: schema: $ref: '#/components/schemas/ChatV1EngineError' components: schemas: ChatV1Error: type: object properties: success: type: boolean example: false error: type: string description: Machine-readable error code or message. example: agent_not_found ChatV1TurnError: type: object description: >- A turn-level conflict or refusal from the chat engine, passed through with the status code the engine gave it. properties: success: type: boolean example: false error: type: string description: Machine-readable error code. example: idempotency_key_reused data: type: object nullable: true description: Extra context when available — typically `turn_id` and `session_id`. example: state: error turn_id: turn_9f3d2a1b session_id: 4718a326-417b-4dda-90d0-21fd65a11cb8 ChatV1EngineError: type: object description: >- Returned when the upstream chat engine rejects or fails a proxied request. properties: success: type: boolean example: false error: type: string example: Python engine returned 422 for POST /v1/chat/session/{id}/support upstream_body: type: object nullable: true description: Parsed error body returned by the chat engine, when available. example: state: rejected reason: tell_not_allowed_during_takeover securitySchemes: ApiToken: type: apiKey in: header name: API-Token description: >- 16-character API token associated with your OSVI account. Find it in your dashboard under Settings → API. ````