> ## Documentation Index > Fetch the complete documentation index at: https://developers.datagrid.com/llms.txt > Use this file to discover all available pages before exploring further. # Create thread message > Posts as the authenticated API user, who must be a channel member. Eligible channel agents may respond and consume credits. ## OpenAPI ````yaml post /channels/{channel_id}/threads/{thread_id}/messages openapi: 3.0.3 info: version: 0.1.1 title: Datagrid API description: Datagrid API servers: - url: https://api.datagrid.com/v1 security: - BearerAuth: [] paths: /channels/{channel_id}/threads/{thread_id}/messages: parameters: - $ref: '#/components/parameters/channel_id' - $ref: '#/components/parameters/thread_id' post: tags: - Channels summary: Create thread message description: >- Posts as the authenticated API user, who must be a channel member. Eligible channel agents may respond and consume credits. operationId: Channels.createThreadMessage requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateChannelMessageRequest' responses: '201': description: Created message content: application/json: schema: $ref: '#/components/schemas/ChannelMessage' components: parameters: channel_id: name: channel_id in: path required: true schema: type: string thread_id: name: thread_id in: path required: true schema: type: string schemas: CreateChannelMessageRequest: type: object required: - content properties: content: type: string maxLength: 20000 file_ids: type: array items: type: string nullable: true ChannelMessage: type: object required: - object - id - channel_id - thread_id - role - agent_id - content - reply_count - reactions - created_at - credits - citations properties: object: type: string enum: - channel.message id: type: string channel_id: type: string thread_id: type: string nullable: true role: type: string enum: - user - agent agent_id: type: string content: type: array items: oneOf: - $ref: '#/components/schemas/MessageContentText' - $ref: '#/components/schemas/MessageContentJson' - $ref: '#/components/schemas/MessageContentVoice' - $ref: '#/components/schemas/MessageContentFile' discriminator: propertyName: type mapping: text: $ref: '#/components/schemas/MessageContentText' json: $ref: '#/components/schemas/MessageContentJson' voice: $ref: '#/components/schemas/MessageContentVoice' input_file: $ref: '#/components/schemas/MessageContentFile' reply_count: type: integer reactions: type: array description: Reactions grouped by emoji, ordered by first reaction time. items: $ref: '#/components/schemas/ChannelMessageReaction' created_at: type: string format: date-time credits: nullable: true allOf: - $ref: '#/components/schemas/OperationCredits' citations: $ref: '#/components/schemas/Citations' nullable: true MessageContentText: type: object description: Text content for a message. required: - type - text properties: type: type: string enum: - text x-stainless-const: true text: type: string description: The text content of the message. MessageContentJson: type: object description: JSON content for structured-output responses. required: - type - json properties: type: type: string enum: - json x-stainless-const: true json: description: The JSON value produced by the agent. MessageContentVoice: type: object description: Voice content for a message. required: - type - audio_clips - transcript - duration_ms properties: type: type: string enum: - voice x-stainless-const: true audio_clips: type: array description: Array of audio clips with timestamps for synchronized playback. items: $ref: '#/components/schemas/VoiceAudioClip' transcript: type: string description: User transcript of the voice message. agent_transcript: type: string description: Agent transcript of the voice message (for agent role messages). nullable: true duration_ms: type: number description: Total duration of the voice message in milliseconds. nullable: true timeline_events: type: array description: >- Per-turn transcript, citation, and tool-call status events in chronological order. Each entry includes a timestamp offset from the start of the voice session. Present only for voice sessions that recorded timeline data. items: $ref: '#/components/schemas/VoiceTimelineEvent' MessageContentFile: type: object description: >- File attachment content for a message. Represents a file that was uploaded as part of the user's message. required: - type - file_id properties: type: type: string enum: - input_file x-stainless-const: true file_id: type: string description: >- The ID of the attached file. Use this ID with the files API to download the file content. ChannelMessageReaction: type: object required: - reaction - users properties: reaction: type: string description: Emoji shortcode or unicode emoji. users: type: array items: $ref: '#/components/schemas/ChannelMessageReactionUser' OperationCredits: type: object required: - consumed properties: consumed: type: number description: The number of credits consumed by the operation. Citations: type: array description: >- Array of citations that provide sources for factual statements in the response. Each citation includes the referenced text and its sources. items: type: object required: - citation - sources properties: citation: type: string description: The text snippet from the response that is being cited. sources: type: array description: Array of sources that support this citation. items: $ref: '#/components/schemas/CitationSource' VoiceAudioClip: type: object description: A single audio clip from a voice message. required: - id - audio_uri - start_time_ms - duration_ms - participant properties: id: type: string description: >- Unique identifier for the audio clip file. Use this ID with the files API to download the audio content. audio_uri: type: string description: Datagrid file URI for the audio file (WAV format). start_time_ms: type: number description: >- Start time of this clip relative to the beginning of the voice message, in milliseconds. duration_ms: type: number description: Duration of this audio clip in milliseconds. participant: type: object description: Participant who spoke in this clip. required: - type - id properties: type: type: string enum: - user - agent id: type: string VoiceTimelineEvent: type: object description: >- A single event from a voice session timeline, representing a transcript turn, citation, or tool-call status update. required: - type - timestamp_ms properties: type: type: string enum: - transcript - citation - tool_call_status description: The type of timeline event. timestamp_ms: type: number description: >- Timestamp offset from the start of the voice session, in milliseconds. role: type: string enum: - user - agent description: The role of the participant for this event. text: type: string description: >- Plain text transcript for this turn. Present when type is 'transcript'. citations: $ref: '#/components/schemas/Citations' description: Citations for this event. Present when type is 'citation'. tool_name: type: string description: >- Name of the tool whose status changed. Present when type is 'tool_call_status'. status: type: string enum: - started - completed - failed description: >- Tool-call status for this event. Present when type is 'tool_call_status'. ChannelMessageReactionUser: type: object required: - user_id - created_at properties: user_id: type: string created_at: type: string format: date-time CitationSource: type: object required: - type - source_name - confirmations properties: type: type: string enum: - image - pdf_page - record - web_search - sql_query_result - action source_id: type: string description: >- Id of the source when Datagrid holds one (dataset id, or data-lake item id for file-backed `pdf_page`). Omitted for `pdf_page` sources with no Datagrid-backed file. source_name: type: string description: Name of the source. source_uri: type: string description: >- URI of the source. For file-backed sources this is the in-app target (signed Datagrid file URI when available); use `external_url` for the origin-system deep-link. For `pdf_page` sources with no Datagrid file, this is the origin-system deep-link and matches `external_url`; locate the page with `page_number`. external_url: type: string description: >- Origin-system deep-link for the source (e.g. an `app.procore.com` universal link), when one exists. Unlike `source_uri`, it is never overridden by the signed Datagrid file URI, so clients can offer an "open in source" action. confirmations: type: array description: An array of text snippets from the source that confirm the citation. items: type: string status: type: string description: >- record only. Primary status value for the record (e.g. "Open", "Pending Review"), surfaced separately from `fields` so clients can render a status chip. fields: type: array description: >- record only. Backend-normalized, render-ready structured fields promoted from the record row (due date, ball-in-court, assignee, revision, type, vendor, scope, …). Excludes `status`, which is surfaced on its own. items: type: object required: - label - value properties: label: type: string description: Human-readable field label (e.g. "Due Date"). value: type: string description: Human-readable field value (e.g. "2025-09-14"). item_type: type: string description: >- record / pdf_page only. Procore tool type of the underlying record (e.g. "rfi_headers", "submittal_logs"), read from the indexed Procore item type on the source row; present only for sources ingested from Procore. Lets clients render a reliable type label (RFI, Submittal, Observation, …) without parsing the deep-link URL. page_number: type: integer minimum: 1 description: >- pdf_page only. 1-based page number within the source document. Omitted when the page is unknown; never `0`. securitySchemes: BearerAuth: type: http scheme: bearer ````