> ## Documentation Index > Fetch the complete documentation index at: https://openai-hd4n6.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Create message > Create a message. ## OpenAPI ````yaml api-definition.yaml post /threads/{thread_id}/messages openapi: 3.0.0 info: title: OpenAI API description: >- The OpenAI REST API. Please see https://platform.openai.com/docs/api-reference for more details. version: 2.3.0 termsOfService: https://openai.com/policies/terms-of-use contact: name: OpenAI Support url: https://help.openai.com/ license: name: MIT url: https://github.com/openai/openai-openapi/blob/master/LICENSE servers: - url: https://api.openai.com/v1 security: - ApiKeyAuth: [] tags: - name: Assistants description: Build Assistants that can call models and use tools. - name: Audio description: Turn audio into text or text into audio. - name: Chat description: >- Given a list of messages comprising a conversation, the model will return a response. - name: Completions description: >- Given a prompt, the model will return one or more predicted completions, and can also return the probabilities of alternative tokens at each position. - name: Embeddings description: >- Get a vector representation of a given input that can be easily consumed by machine learning models and algorithms. - name: Evals description: Manage and run evals in the OpenAI platform. - name: Fine-tuning description: Manage fine-tuning jobs to tailor a model to your specific training data. - name: Batch description: Create large batches of API requests to run asynchronously. - name: Files description: >- Files are used to upload documents that can be used with features like Assistants and Fine-tuning. - name: Uploads description: Use Uploads to upload large files in multiple parts. - name: Images description: Given a prompt and/or an input image, the model will generate a new image. - name: Models description: List and describe the various models available in the API. - name: Moderations description: >- Given text and/or image inputs, classifies if those inputs are potentially harmful. - name: Audit Logs description: List user actions and configuration changes within this organization. paths: /threads/{thread_id}/messages: post: tags: - Assistants summary: Create message description: Create a message. operationId: createMessage parameters: - in: path name: thread_id required: true schema: type: string description: >- The ID of the [thread](/docs/api-reference/threads) to create a message for. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateMessageRequest' responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/MessageObject' components: schemas: CreateMessageRequest: type: object additionalProperties: false required: - role - content properties: role: type: string enum: - user - assistant description: > The role of the entity that is creating the message. Allowed values include: - `user`: Indicates the message is sent by an actual user and should be used in most cases to represent user-generated messages. - `assistant`: Indicates the message is generated by the assistant. Use this value to insert messages from the assistant into the conversation. content: oneOf: - type: string description: The text contents of the message. title: Text content - type: array description: >- An array of content parts with a defined type, each can be of type `text` or images can be passed with `image_url` or `image_file`. Image types are only supported on [Vision-compatible models](/docs/models). title: Array of content parts items: oneOf: - $ref: '#/components/schemas/MessageContentImageFileObject' - $ref: '#/components/schemas/MessageContentImageUrlObject' - $ref: '#/components/schemas/MessageRequestContentTextObject' x-oaiExpandable: true minItems: 1 x-oaiExpandable: true attachments: type: array items: type: object properties: file_id: type: string description: The ID of the file to attach to the message. tools: description: The tools to add this file to. type: array items: oneOf: - $ref: '#/components/schemas/AssistantToolsCode' - $ref: '#/components/schemas/AssistantToolsFileSearchTypeOnly' x-oaiExpandable: true description: >- A list of files attached to the message, and the tools they should be added to. required: - file_id - tools nullable: true metadata: $ref: '#/components/schemas/Metadata' MessageObject: type: object title: The message object description: Represents a message within a [thread](/docs/api-reference/threads). properties: id: description: The identifier, which can be referenced in API endpoints. type: string object: description: The object type, which is always `thread.message`. type: string enum: - thread.message x-stainless-const: true created_at: description: The Unix timestamp (in seconds) for when the message was created. type: integer thread_id: description: >- The [thread](/docs/api-reference/threads) ID that this message belongs to. type: string status: description: >- The status of the message, which can be either `in_progress`, `incomplete`, or `completed`. type: string enum: - in_progress - incomplete - completed incomplete_details: description: >- On an incomplete message, details about why the message is incomplete. type: object properties: reason: type: string description: The reason the message is incomplete. enum: - content_filter - max_tokens - run_cancelled - run_expired - run_failed nullable: true required: - reason completed_at: description: The Unix timestamp (in seconds) for when the message was completed. type: integer nullable: true incomplete_at: description: >- The Unix timestamp (in seconds) for when the message was marked as incomplete. type: integer nullable: true role: description: The entity that produced the message. One of `user` or `assistant`. type: string enum: - user - assistant content: description: The content of the message in array of text and/or images. type: array items: oneOf: - $ref: '#/components/schemas/MessageContentImageFileObject' - $ref: '#/components/schemas/MessageContentImageUrlObject' - $ref: '#/components/schemas/MessageContentTextObject' - $ref: '#/components/schemas/MessageContentRefusalObject' x-oaiExpandable: true assistant_id: description: >- If applicable, the ID of the [assistant](/docs/api-reference/assistants) that authored this message. type: string nullable: true run_id: description: >- The ID of the [run](/docs/api-reference/runs) associated with the creation of this message. Value is `null` when messages are created manually using the create message or create thread endpoints. type: string nullable: true attachments: type: array items: type: object properties: file_id: type: string description: The ID of the file to attach to the message. tools: description: The tools to add this file to. type: array items: oneOf: - $ref: '#/components/schemas/AssistantToolsCode' - $ref: '#/components/schemas/AssistantToolsFileSearchTypeOnly' x-oaiExpandable: true description: >- A list of files attached to the message, and the tools they were added to. nullable: true metadata: $ref: '#/components/schemas/Metadata' required: - id - object - created_at - thread_id - status - incomplete_details - completed_at - incomplete_at - role - content - assistant_id - run_id - attachments - metadata x-oaiMeta: name: The message object beta: true example: | { "id": "msg_abc123", "object": "thread.message", "created_at": 1698983503, "thread_id": "thread_abc123", "role": "assistant", "content": [ { "type": "text", "text": { "value": "Hi! How can I help you today?", "annotations": [] } } ], "assistant_id": "asst_abc123", "run_id": "run_abc123", "attachments": [], "metadata": {} } MessageContentImageFileObject: title: Image file type: object description: >- References an image [File](/docs/api-reference/files) in the content of a message. properties: type: description: Always `image_file`. type: string enum: - image_file x-stainless-const: true image_file: type: object properties: file_id: description: >- The [File](/docs/api-reference/files) ID of the image in the message content. Set `purpose="vision"` when uploading the File if you need to later display the file content. type: string detail: type: string description: >- Specifies the detail level of the image if specified by the user. `low` uses fewer tokens, you can opt in to high resolution using `high`. enum: - auto - low - high default: auto required: - file_id required: - type - image_file MessageContentImageUrlObject: title: Image URL type: object description: References an image URL in the content of a message. properties: type: type: string enum: - image_url description: The type of the content part. x-stainless-const: true image_url: type: object properties: url: type: string description: >- The external URL of the image, must be a supported image types: jpeg, jpg, png, gif, webp. format: uri detail: type: string description: >- Specifies the detail level of the image. `low` uses fewer tokens, you can opt in to high resolution using `high`. Default value is `auto` enum: - auto - low - high default: auto required: - url required: - type - image_url MessageRequestContentTextObject: title: Text type: object description: The text content that is part of a message. properties: type: description: Always `text`. type: string enum: - text x-stainless-const: true text: type: string description: Text content to be sent to the model required: - type - text AssistantToolsCode: type: object title: Code interpreter tool properties: type: type: string description: 'The type of tool being defined: `code_interpreter`' enum: - code_interpreter x-stainless-const: true required: - type AssistantToolsFileSearchTypeOnly: type: object title: FileSearch tool properties: type: type: string description: 'The type of tool being defined: `file_search`' enum: - file_search x-stainless-const: true required: - type Metadata: type: object description: > Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format, and querying for objects via API or the dashboard. Keys are strings with a maximum length of 64 characters. Values are strings with a maximum length of 512 characters. additionalProperties: type: string x-oaiTypeLabel: map nullable: true MessageContentTextObject: title: Text type: object description: The text content that is part of a message. properties: type: description: Always `text`. type: string enum: - text x-stainless-const: true text: type: object properties: value: description: The data that makes up the text. type: string annotations: type: array items: oneOf: - $ref: >- #/components/schemas/MessageContentTextAnnotationsFileCitationObject - $ref: >- #/components/schemas/MessageContentTextAnnotationsFilePathObject x-oaiExpandable: true required: - value - annotations required: - type - text MessageContentRefusalObject: title: Refusal type: object description: The refusal content generated by the assistant. properties: type: description: Always `refusal`. type: string enum: - refusal x-stainless-const: true refusal: type: string nullable: false required: - type - refusal MessageContentTextAnnotationsFileCitationObject: title: File citation type: object description: >- A citation within the message that points to a specific quote from a specific File associated with the assistant or the message. Generated when the assistant uses the "file_search" tool to search files. properties: type: description: Always `file_citation`. type: string enum: - file_citation x-stainless-const: true text: description: The text in the message content that needs to be replaced. type: string file_citation: type: object properties: file_id: description: The ID of the specific File the citation is from. type: string required: - file_id start_index: type: integer minimum: 0 end_index: type: integer minimum: 0 required: - type - text - file_citation - start_index - end_index MessageContentTextAnnotationsFilePathObject: title: File path type: object description: >- A URL for the file that's generated when the assistant used the `code_interpreter` tool to generate a file. properties: type: description: Always `file_path`. type: string enum: - file_path x-stainless-const: true text: description: The text in the message content that needs to be replaced. type: string file_path: type: object properties: file_id: description: The ID of the file that was generated. type: string required: - file_id start_index: type: integer minimum: 0 end_index: type: integer minimum: 0 required: - type - text - file_path - start_index - end_index securitySchemes: ApiKeyAuth: type: http scheme: bearer ````