> ## Documentation Index > Fetch the complete documentation index at: https://flowdrop.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Get category definitions > Retrieve all available category definitions including display labels, icons, colors, and ordering. Categories determine how nodes are organized in the sidebar. Built-in categories are always available as defaults. This endpoint allows overriding built-in category metadata and defining custom categories. ## OpenAPI ````yaml /api-reference/openapi.yaml get /categories openapi: 3.0.3 info: title: FlowDrop™ API description: > FlowDrop is a visual workflow editor for AI applications and data processing pipelines. This API provides comprehensive endpoints for managing workflows, node types, pipeline execution, and port configuration. ## Features - **Workflow Management**: Complete CRUD operations for workflows with nodes and edges - **Node Type Discovery**: Browse and search available node processors with metadata - **Pipeline Execution**: Execute workflows with real-time status tracking and job management - **Port Configuration**: Dynamic port compatibility system with data type management - **Real-time Updates**: Track node execution status and pipeline progress - **Import/Export**: Import and export workflows in JSON format - **Validation**: Workflow validation before execution - **Agent Spec Integration**: Import/export Oracle Open Agent Spec flows and execute on compatible runtimes (WayFlow/PyAgentSpec) ## Architecture - **Frontend**: Svelte 5 + XYFlow for visual workflow editing - **Backend**: Drupal 10/11 with custom node processor plugins - **API**: RESTful JSON API with consistent response format - **Storage**: Drupal entity system with workflow versioning ## Authentication API endpoints require Drupal authentication. Use Bearer token or session-based authentication. ## Rate Limiting - Node Discovery: 100 requests/minute - Workflow Operations: 50 requests/minute - Pipeline Execution: 20 requests/minute ## Error Handling All errors return a consistent format with success flag, error message, and optional details. version: 1.0.0 contact: name: FlowDrop Support email: shibinkidd@gmail.com url: https://www.drupal.org/project/issues/flowdrop?categories=All servers: - url: http://localhost:5173/api/flowdrop description: Local development server (Svelte) - url: https://flowdrop.ddev.site/api/flowdrop description: Local Drupal server security: - BearerAuth: [] - SessionAuth: [] tags: - name: System description: System health and status endpoints - name: Node Types description: Node type discovery and metadata endpoints - name: Configuration description: System configuration endpoints including port configuration - name: Workflows description: Workflow CRUD operations - name: Pipeline description: Pipeline execution and monitoring - name: Playground description: Interactive workflow testing and chat interface - name: Interrupts description: | Human-in-the-Loop (HITL) interrupt endpoints for workflow interactions. Interrupts allow workflows to pause execution and request user input. - name: Validation description: Workflow validation - name: Import/Export description: Workflow import and export operations - name: Chat description: | LLM Chat Interface for natural language workflow building. Translates user intent into DSL commands via a backend LLM integration. - name: Agent Spec description: > Oracle Open Agent Spec integration endpoints. Provides bidirectional conversion between FlowDrop workflows and Agent Spec format, plus runtime execution on compatible runtimes (WayFlow, PyAgentSpec). @see https://github.com/oracle/agent-spec paths: /categories: get: tags: - Configuration summary: Get category definitions description: > Retrieve all available category definitions including display labels, icons, colors, and ordering. Categories determine how nodes are organized in the sidebar. Built-in categories are always available as defaults. This endpoint allows overriding built-in category metadata and defining custom categories. operationId: getCategories responses: '200': description: Categories retrieved successfully content: application/json: schema: $ref: '#/components/schemas/CategoriesResponse' example: success: true data: - name: triggers label: Triggers icon: mdi:lightning-bolt color: var(--fd-node-cyan) weight: 0 - name: inputs label: Inputs icon: mdi:arrow-down-circle color: var(--fd-node-emerald) weight: 1 - name: ml label: Machine Learning icon: mdi:brain color: var(--fd-node-purple) description: Custom ML processing nodes weight: 20 message: Categories loaded successfully '401': $ref: '#/components/responses/Unauthorized' '500': $ref: '#/components/responses/InternalServerError' components: schemas: CategoriesResponse: allOf: - $ref: '#/components/schemas/ApiResponse' - type: object properties: data: type: array items: $ref: '#/components/schemas/CategoryDefinition' ApiResponse: type: object properties: success: type: boolean description: Whether the request was successful data: description: Response data (type varies by endpoint) message: type: string description: Response message error: type: string description: Error message (if any) CategoryDefinition: type: object description: | Category definition with metadata for display and organization. Returned by the `/categories` endpoint. properties: name: type: string description: Machine name / unique identifier example: ml label: type: string description: Display label shown in UI example: Machine Learning icon: type: string description: Icon identifier (Iconify format) example: mdi:brain color: type: string description: Color token or CSS value example: var(--fd-node-purple) description: type: string description: Category description example: Machine learning and AI model nodes weight: type: number description: Sort weight for ordering (lower = earlier) example: 20 required: - name - label ErrorResponse: allOf: - $ref: '#/components/schemas/ApiResponse' - type: object properties: success: type: boolean example: false error: type: string description: Error message code: type: string description: Error code details: type: object description: Additional error details responses: Unauthorized: description: Unauthorized - authentication required content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: success: false error: Authentication required code: UNAUTHORIZED InternalServerError: description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: success: false error: Internal server error code: INTERNAL_ERROR securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: JWT description: JWT token for authentication SessionAuth: type: apiKey in: cookie name: SESS description: Drupal session cookie ````