> ## Documentation Index > Fetch the complete documentation index at: https://yukta.infenia.com/llms.txt > Use this file to discover all available pages before exploring further. # Apply session configuration > Initializes a new session or updates an existing session's configuration at runtime, including its workflow definitions ## OpenAPI ````yaml /api/openapi.json post /api/sessions openapi: 3.1.0 info: title: Yukta REST API version: 0.0.1-SNAPSHOT description: >- Create sessions and workflows, start and steer executions, and read their status, logs and results. Pre-beta: paths and schemas may change before v0.1.0. servers: - url: http://localhost:8080 description: Local server (default address) security: - bearerAuth: [] - apiKeyAuth: [] tags: - name: Supervisors API description: Supervisors and control planes on the control bus - name: Workflow Versions API description: List the saved versions and roll back - name: Workflow API description: Endpoints for starting workflows and listing their executions - name: Execution API description: Stop, restart and observe workflow executions - name: Execution Search API description: Find runs across sessions - name: Control Bus & Observability API description: >- Endpoints for control bus operations, node management, and execution observability - name: Execution Control API description: Pause, resume, step and stop nodes - name: Session API description: Endpoints for session and workflow discovery, configuration management - name: Session API description: Validate a draft workflow without saving it - name: Workers API description: Workers connected to the control plane - name: Events API description: Live feed of execution events - name: Workflow Details API description: Workflow DAG graph with plugin metadata and per-workflow execution history - name: Execution Results API description: Follow the result of an execution - name: Execution Logs API description: Stream execution logs - name: Control audit API description: Control commands and who sent them - name: Plugin API description: Endpoints for discovering workflow plugins paths: /api/sessions: post: tags: - Session API summary: Apply session configuration description: >- Initializes a new session or updates an existing session's configuration at runtime, including its workflow definitions operationId: applyConfig requestBody: content: application/json: schema: $ref: '#/components/schemas/ConfigRequest' required: true responses: '200': description: OK content: '*/*': schema: $ref: '#/components/schemas/ApiResponseVoid' components: schemas: ConfigRequest: type: object description: >- Request object for session configuration, supporting both initialization and runtime updates properties: sessionId: type: string description: The unique session identifier used to track this context example: session-123 maxLength: 256 minLength: 0 pattern: ^(?!.*\.\.)[^/\\]*$ name: type: string description: A human-readable name for the session example: Production ETL v4 maxLength: 256 minLength: 0 description: type: string description: A human-readable description of the session example: Daily build and quality check maxLength: 256 minLength: 0 initiator: type: string description: The name of the initiator (user or system) example: AI Agent minLength: 1 tags: type: object additionalProperties: type: string description: Metadata tags for categorization and filtering example: environment: prod client: mobile-app projectPath: type: string description: The absolute root path of the project on the server's filesystem example: /home/user/workspace/project-alpha maxLength: 1024 minLength: 0 workflows: type: object additionalProperties: $ref: '#/components/schemas/WorkflowDefinitionRequest' description: A map of workflow definition requests keyed by workflow ID minProperties: 1 required: - description - initiator - name - projectPath - sessionId - workflows ApiResponseVoid: type: object description: >- Unified API response wrapper for both success and error responses. Success responses include data field; error responses include error, path, and errors fields. properties: timestamp: type: string format: date-time description: The time the response was generated status: type: integer format: int32 description: The HTTP status code example: 200 message: type: string description: A human-readable message example: Operation successful data: description: The response data error: type: string description: The HTTP status error name example: Bad Request path: type: string description: The request path example: /api/files errors: type: array description: The list of field validation errors items: $ref: '#/components/schemas/FieldError' WorkflowDefinitionRequest: type: object description: Definition of a reactive workflow DAG properties: workflowId: type: string description: Unique workflow identifier minLength: 1 description: type: string description: A human-readable description of the workflow example: Quality check maxLength: 256 minLength: 0 nodes: type: array description: Nodes in the workflow items: $ref: '#/components/schemas/NodeRequest' minItems: 1 edges: type: array description: Edges connecting the nodes items: $ref: '#/components/schemas/EdgeRequest' required: - description - edges - nodes - workflowId FieldError: type: object description: Field-specific validation error detail properties: field: type: string description: The name of the field that failed validation example: sessionId message: type: string description: The validation error message explaining the failure example: 'Session not found: ''unknown-session''' NodeRequest: type: object description: A single node in the workflow DAG properties: nodeId: type: string description: Unique ID for the node minLength: 1 type: type: string description: Plugin type minLength: 1 config: type: object additionalProperties: {} description: Plugin configuration required: - nodeId - type EdgeRequest: type: object description: A connection between two nodes properties: source: type: string description: Source node ID minLength: 1 target: type: string description: Target node ID minLength: 1 sourcePort: type: string description: Source port name (optional; omit to route all messages) required: - source - target securitySchemes: bearerAuth: type: http scheme: bearer description: >- API key sent as `Authorization: Bearer `. Needed only when the server has a key configured. apiKeyAuth: type: apiKey in: header name: X-API-Key description: The same API key sent as `X-API-Key`. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.