> ## Documentation Index > Fetch the complete documentation index at: https://docs.guild.ai/llms.txt > Use this file to discover all available pages before exploring further. # Post a follow-up event to a session > Requires `sessions:write`. The message is authored by the key itself (`author.type: "api_key"`) -- a key may never author as anyone else. The `agent_id` field is accepted but ignored for a key, so a key cannot switch which agent answers mid-conversation; start a new session instead. A key converses only in the chat sessions it initiated -- posting into any other session (another key's chat, a person's chat, a trigger session) is `404`. ## OpenAPI ````yaml /api-reference/openapi.yaml post /sessions/{session_id}/events openapi: 3.0.3 info: title: Guild Public API version: 1.0.0 description: >- The Guild public API, served at https://api.guild.ai/v1 and authenticated with account API keys (HTTP Basic, key id as the username and the secret as the password). See https://docs.guild.ai/api-reference/introduction for scopes and behavior. A session-events websocket also exists at wss://api.guild.ai/v1/sessions/{session_id}/events/ws with the same Basic auth on the handshake; OpenAPI cannot describe websockets, so it is not listed in paths. servers: - url: https://api.guild.ai/v1 description: Production security: [] tags: - name: accounts - name: agents - name: sessions - name: skills - name: workspaces paths: /sessions/{session_id}/events: post: tags: - sessions summary: Post a follow-up event to a session description: >- Requires `sessions:write`. The message is authored by the key itself (`author.type: "api_key"`) -- a key may never author as anyone else. The `agent_id` field is accepted but ignored for a key, so a key cannot switch which agent answers mid-conversation; start a new session instead. A key converses only in the chat sessions it initiated -- posting into any other session (another key's chat, a person's chat, a trigger session) is `404`. operationId: create_session_event parameters: - name: session_id in: path required: true schema: type: string format: uuid requestBody: required: false content: application/json: schema: anyOf: - $ref: '#/components/schemas/CreateTextSessionEventInput' - $ref: '#/components/schemas/CreateJsonSessionEventInput' - $ref: '#/components/schemas/CreateMultimodalSessionEventInput' - $ref: '#/components/schemas/CreateMultipartSessionEventInput' responses: '200': description: Successful response content: application/json: schema: $ref: '#/components/schemas/Event' '400': description: Bad Request content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '403': description: Forbidden content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' security: - apiKey: [] components: schemas: CreateTextSessionEventInput: properties: agent_id: default: null title: Agent Id nullable: true type: string selected_skills: default: null title: Selected Skills nullable: true items: type: string type: array content: title: Content type: string mode: default: text title: Mode type: string enum: - text required: - content title: CreateTextSessionEventInput type: object CreateJsonSessionEventInput: properties: agent_id: default: null title: Agent Id nullable: true type: string selected_skills: default: null title: Selected Skills nullable: true items: type: string type: array content: additionalProperties: true title: Content type: object mode: title: Mode type: string enum: - json required: - content - mode title: CreateJsonSessionEventInput type: object CreateMultimodalSessionEventInput: properties: agent_id: default: null title: Agent Id nullable: true type: string selected_skills: default: null title: Selected Skills nullable: true items: type: string type: array content: items: $ref: '#/components/schemas/_MultimodalContentPart' minItems: 1 title: Content type: array mode: title: Mode type: string enum: - multimodal required: - content - mode title: CreateMultimodalSessionEventInput type: object CreateMultipartSessionEventInput: properties: agent_id: default: null title: Agent Id nullable: true type: string selected_skills: default: null title: Selected Skills nullable: true items: type: string type: array content: additionalProperties: true title: Content type: object mode: title: Mode type: string enum: - multipart required: - content - mode title: CreateMultipartSessionEventInput type: object Event: oneOf: - $ref: '#/components/schemas/EventContainerLog' - $ref: '#/components/schemas/EventAgentConsole' - $ref: '#/components/schemas/EventAgentInstallRequest' - $ref: '#/components/schemas/EventAgentNotificationError' - $ref: '#/components/schemas/EventAgentNotificationMessage' - $ref: '#/components/schemas/EventAgentNotificationProgress' - $ref: '#/components/schemas/EventCredentialsRequest' - $ref: '#/components/schemas/EventInterrupted' - $ref: '#/components/schemas/EventLlmDone' - $ref: '#/components/schemas/EventLlmStart' - $ref: '#/components/schemas/EventRuntimeDone' - $ref: '#/components/schemas/EventRuntimeError' - $ref: '#/components/schemas/EventRuntimeRunning' - $ref: '#/components/schemas/EventRuntimeStart' - $ref: '#/components/schemas/EventRuntimeWaiting' - $ref: '#/components/schemas/EventSecurity' - $ref: '#/components/schemas/EventSystemError' - $ref: '#/components/schemas/EventSystemMessage' - $ref: '#/components/schemas/EventTriggerMessage' - $ref: '#/components/schemas/EventUserMessage' ErrorResponse: type: object properties: error: type: string message: type: string _MultimodalContentPart: discriminator: mapping: file: $ref: '#/components/schemas/_AttachmentContentPart' image: $ref: '#/components/schemas/_AttachmentContentPart' text: $ref: '#/components/schemas/_TextContentPart' propertyName: type oneOf: - $ref: '#/components/schemas/_TextContentPart' - $ref: '#/components/schemas/_AttachmentContentPart' EventContainerLog: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time task_id: type: string format: uuid level: type: string enum: - INFO - ERROR nullable: true description: >- Severity of the line: INFO for ordinary output, ERROR for error-level output. Nullable for now; pre-existing rows have no level. message: type: string timestamp: type: string format: date-time description: When the line was produced in the container (not received) type: {} EventAgentConsole: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: string level: type: string enum: - DEBUG - INFO - WARN - ERROR task_id: type: string format: uuid type: {} EventAgentInstallRequest: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time requested_agent_id: type: string format: uuid description: The agent requested to be installed task_id: type: string format: uuid installed_agent_id: type: string format: uuid nullable: true description: The workspace agent created when this request was fulfilled processed_at: type: string format: date-time nullable: true description: If the request has been declined, this is when it happened. processed_by_id: type: string format: uuid nullable: true description: The user who declined or accepted this request, if applicable. agent: {} installed_agent: {} is_fulfilled: {} requested_agent: {} type: {} EventAgentNotificationError: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid data: {} type: {} EventAgentNotificationMessage: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid type: {} EventAgentNotificationProgress: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid type: {} EventCredentialsRequest: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time auth_config_id: type: string format: uuid description: The auth config this credentials should use task_id: type: string format: uuid is_fulfilled: type: boolean description: >- Indicates whether the request has been fulfilled. Skipped requests are also marked fulfilled (see skipped_at). If it is set to true, credentials is null, and skipped_at is null, it means the credentials has been deleted later. credentials_id: type: string format: uuid nullable: true description: The credentials created when this request was fulfilled skipped_at: type: string format: date-time nullable: true description: If the request was skipped, when it happened. skipped_by_id: type: string format: uuid nullable: true description: The user who skipped this request, if applicable. target_account_id: type: string format: uuid nullable: true description: >- The account the credentials should be installed in, if applicable. This is used by The Smith to request installs in other accounts. agent: {} integration: {} target_account: {} type: {} EventInterrupted: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time interrupted_at: type: string format: date-time description: Timestamp when the session was interrupted interrupted_by_id: type: string format: uuid description: User who interrupted the session task_id: type: string format: uuid interrupted_by: {} type: {} EventLlmDone: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time body: type: string headers: type: object llm_event_id: type: string format: uuid status_code: type: integer task_id: type: string format: uuid type: {} EventLlmStart: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time headers: type: object inference_provider_id: type: string format: uuid llm_provider: type: string enum: - ANTHROPIC - OPENAI - GEMINI - FAKE_LLM - META payload: type: object task_id: type: string format: uuid llm_model: type: string maxLength: 100 nullable: true model: {} provider: {} type: {} EventRuntimeDone: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid type: {} EventRuntimeError: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: string task_id: type: string format: uuid stack: type: string nullable: true type: {} EventRuntimeRunning: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time task_id: type: string format: uuid type: {} EventRuntimeStart: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid type: {} EventRuntimeWaiting: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time task_id: type: string format: uuid type: {} EventSecurity: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time decision: type: string enum: - ALLOW - DENY - ERROR description: Security decision outcome. message: type: string description: Human-readable security event summary. operation: type: string maxLength: 255 description: Integration operation or action evaluated. reason_code: type: string enum: - POLICY_DENIED - CREDENTIAL_UNAVAILABLE - PRIVILEGE_ESCALATION_DENIED - PLATFORM_ACCESS_DENIED - ACCESS_ALLOWED description: Stable machine code for why the decision occurred. task_id: type: string format: uuid acting_user_id: type: string format: uuid nullable: true description: Human acting on behalf of the task when the decision was recorded. capability: type: string maxLength: 32 nullable: true description: Capability evaluated for this decision (read, write, delete, admin). credentials_id: type: string format: uuid nullable: true description: Credentials involved in the security decision when applicable. details: type: object nullable: true description: Optional structured audit context beyond task/session links. acting_user: {} credentials: {} integration: {} task: {} type: {} EventSystemError: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time details: type: object description: An arbitrary JSON object that stores details about the error. message: type: string description: A user-visible message that describes the error that occurred. task_id: type: string format: uuid content: {} data: {} type: {} EventSystemMessage: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid data: {} type: {} EventTriggerMessage: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time content: type: object task_id: type: string format: uuid data: {} type: {} EventUserMessage: type: object properties: id: type: string format: uuid created_at: type: string format: date-time updated_at: type: string format: date-time author_id: type: string format: uuid description: >- Who sent this message: a user, or an account API key relaying a conversation on behalf of its account. content: type: array items: {} task_id: type: string format: uuid author: {} content_parts: {} type: {} _AttachmentContentPart: properties: type: enum: - image - file title: Type type: string attachment_id: format: uuid title: Attachment Id type: string required: - type - attachment_id title: _AttachmentContentPart type: object _TextContentPart: properties: type: title: Type type: string enum: - text text: title: Text type: string required: - type - text title: _TextContentPart type: object securitySchemes: apiKey: type: http scheme: basic description: 'Account API key: key id as the username, secret as the password.' ````