From 05a31cf976918df85b108cf054e91b125139f9c4 Mon Sep 17 00:00:00 2001 From: Ran Date: Tue, 18 Nov 2025 13:40:47 +0200 Subject: [PATCH] chore: prepend product changelog for 2025-11-18 (Generalist Agent Revamp, MCP Client, Activity Log Enhancements) --- changelog/product-updates.mdx | 752 ++-------------------------------- 1 file changed, 37 insertions(+), 715 deletions(-) diff --git a/changelog/product-updates.mdx b/changelog/product-updates.mdx index 210f337..672c0d2 100644 --- a/changelog/product-updates.mdx +++ b/changelog/product-updates.mdx @@ -4,731 +4,53 @@ mode: 'wide' rss: true --- - -Today's update is relatively short due to the last update being 4 days ago. We're now moving to a weekly update every Sunday. + ## New Features: -- **OpenAI GPT-5.1 Model Support:** Added GPT-5.1 and additional GPT-5 family variants to the model catalog, with updated context and output token limits for each model. -- **Agent Description Field:** Introduced editable agent descriptions in the Workbench and auto-generation of agent descriptions. This will be populated in the Agents list in app.xpander.ai and chat.xpander.ai (or chat.your-company.com) -- **Improved robustness of Task scheduler:** Migrated platform services to async Redis clients and offloaded non-critical work to background tasks for improved throughput and reliability. +- **Generalist Agent Revamp:** Major overhaul of the generalist agent experience, including step-by-step reasoning API, task grouping in the WebUI, persistent agent memories, and improved orchestration for tool calls and sub-tasks. +- **MCP Client Integration:** The MCP client has been relocated into the Agents service, providing unified endpoints for listing and invoking MCP tools with robust HTTP/SSE transport detection, retries, and structured result parsing. +- **Session and Tool Duration Tracking:** Activity logs now display total session duration and per-tool execution times, improving observability and debugging. +- **Agent Description Field:** Agents now support editable descriptions, with auto-generation for missing values, enhancing discoverability and clarity in the UI. +- **OAuth2 CLI Login Flow:** Streamlined OAuth2 login for CLI users, with automatic API key selection and secure callback redirects. ## Improvements: -- **Environment Management:** Added option to configure default environment for agent deployments. -- **Agent Activity Logs UI:** Refined agent activity logs to group user turns, tool calls, and assistant answers for improved readability. -- **UI/UX Enhancements:** Improved chat background color handling, loader states for iframe chat initialization, and clarified terminology (e.g., "Executions" to "Tasks"). -- **Connector and API Key Management:** Added SQL functions for environment filtering, improved API key selection in OAuth2 flows, and refined connector versioning logic. +- **WebUI and Chainlit Enhancements:** + - Task grouping and parented tool/sub-task steps in the Chainlit UI. + - Improved streaming, error handling, and security headers for hosted assistants. + - Refined CSS to reduce visual clutter and improve accessibility. + - Loader states and progress indicators for iframe chat initialization and pending tasks. +- **Agent Activity Logs:** + - Grouped user turns, tool calls, and assistant answers for improved readability. + - Display of input/output LLM token metrics and per-turn durations. + - Robust parsing of tool call payloads and headers for clearer operation tooltips. +- **Environment and Deployment Management:** + - Unified environment handling with clear default logic and improved sorting. + - Enhanced SQL functions for filtering non-default environments with deployments. +- **Model Catalog Expansion:** + - Added GPT-5.1 and additional GPT-5 family variants to the model catalog, with updated context and output token limits. +- **Authentication and Security:** + - Hardened OIDC and WebUI authentication flows with safe redirect handling and improved session recovery. + - Support for passing redirect URLs and metadata through OIDC login and callback flows. ## Bug Fixes: -- **UI Consistency:** Resolved various UI bugs, including modal race conditions, built-in tool toggling, metrics tab rendering, and chat view background color. -- **OAuth2 CLI Flow:** Improved OAuth2 CLI login flow with API key selection, authorization UI, and safe redirect handling. +- **Async Platform Stabilization:** + - Resolved failures in agentic task runs by aligning the scheduler and job executor with async execution models. + - Fixed event-loop conflicts and improved error handling in scheduled jobs. +- **Agent Execution and Activity Export:** + - Fixed thread export in agent activity by ensuring unique message serialization and returning serializable session data. + - Addressed missing execution records during task updates by enabling upsert-on-missing logic. +- **Billing and Quota Calculation:** + - Corrected billing quota usage calculations by aligning with entitlement-based usage limits and sunsetting the MCP service in workflows. +- **UI Consistency and Minor Fixes:** + - Addressed various UI bugs, including modal race conditions, loader states, chat background color, and metrics tab rendering. + - Improved error propagation and PII error handling in activity threads. + - Fixed metrics aggregation and token metrics display in activity logs. + - Ensured robust handling of tool-call reporting, agent error flows, and tool result extraction in the UI. - -## New Features: - -- **OAuth 2.1 Authorization Server:** Introduced a full OAuth 2.1 server with Remote OAuth and Dynamic Client Registration for MCP and API endpoints, including JWT-based authentication and discovery endpoints. Check out the API reference here: https://docs.xpander.ai/api-reference -- **Workbench: Built-in Tools:** Added toggles to enable/disable built-in tools like email sending and sleep toold in the Workbench Tools tab. -- **Guardrails and Agno Settings:** Expanded agent guardrails configuration, including PII detection, prompt injection detection, and OpenAI moderation categories. -- **Agent Version Naming:** Added support for naming agent versions, with editable version names displayed throughout the UI. - - -## Improvements: - -- **Agent Activity Token Metrics:** Exposed input and output LLM token breakdowns in agent activity threads and sessions for improved monitoring and billing. -- **Connector Versioning and Upgrade Flow:** Improved connectors table with version selectors, upgrade confirmation dialogs, and better version management. -- **UI/UX Enhancements:** Refined metrics counting, improved modal and tab behaviors, clarified terminology (e.g., "Executions" to "Tasks"), and enhanced error handling and session management. - - -## Bug Fixes: - -- **Tool-Call Reporting and Error Flow:** Improved reliability of tool-call lifecycle reporting, error event emission, and UI rendering for tool-call steps. -- **Thread Activity Metrics:** Corrected token metrics display and layout in thread activity views, ensuring accurate input/output token counts. -- **UI Consistency:** Resolved various UI bugs, including modal race conditions, built-in tool toggling, and metrics tab rendering. -- **Connector and Agent Settings:** Fixed issues with connector version selection, upload modal behavior, and agent settings persistence. - - - - - -## New Features: - -- **MCP Connector Management:** Complete UI for creating, managing, and configuring MCP connectors with tool visualization and server selection. -- **Environment Configuration:** Enhanced environment settings with sorting, deletion, and configuration management capabilities. - -## Improvements: - -- **Tool Picker Panel:** Redesigned tool selection interface with improved usability and select-all functionality. -- **Connector Operations:** Streamlined connector creation and deletion workflows. - -## Bug Fixes: - -- **MCP Server Display:** Fixed MCP server table rendering and connector display issues. -- **Environment UI:** Resolved environment skeleton loading and configuration bugs. - - - - - -## New Features: - -- **On-Premise Streaming:** Real-time streaming support for on-premise deployments with improved performance. -- **Deployed Assets Management:** Comprehensive management interface for deployed assets and configurations. - -## Improvements: - -- **Environment Types:** Enhanced environment type enforcement and validation mechanisms. -- **Self-Hosted UI:** Improved self-hosted configuration panels and settings interface. - -## Bug Fixes: - -- **Streaming Text:** Fixed text streaming issues in on-premise environments. -- **Environment ID Handling:** Resolved environment ID tracking and validation bugs. - - - - - -## New Features: - -- **User Groups:** Enterprise-grade access control with user group creation and management. -- **Default Group Assignment:** Automatic group assignment for new users with customizable defaults. -- **Granular Permissions:** Fine-grained permission controls at the organizational level. - -## Improvements: - -- **Settings Refactor:** Separated user and admin settings for better organization. -- **Onboarding:** Added option to skip onboarding questionnaire for existing users. - -## Bug Fixes: - -- **Group Enforcement:** Fixed user group enforcement and edge function hooks. -- **Permission Validation:** Resolved permission validation edge cases. - - - - - -## New Features: - -- **Agent Teams:** Multi-agent coordination with coordinate mode for complex workflows. -- **Bot-to-Bot Communication:** Direct communication support between agents. -- **Sub-Agent Executions:** Hierarchical agent execution with enqueue mechanism. - -## Improvements: - -- **Team Mode UI:** Enhanced team mode interface with coordinate mode toggle. -- **Agent Hub:** Improved agent discovery and template selection. - -## Bug Fixes: - -- **Team Sessions:** Fixed session management for team-based workflows. -- **Agent Activity Tracking:** Resolved monitoring and tracking issues for team agents. - - - - - -## New Features: - -- **Agno 2.0 Integration:** Complete migration to Agno 2.0 framework for enhanced performance. -- **Team Mode Sessions:** Advanced session management from Agno for team workflows. - -## Improvements: - -- **Performance:** Significant performance improvements across agent execution. -- **Reliability:** Enhanced stability and error handling throughout the platform. - - - - - -## New Features: - -- **Connectors v2:** Redesigned connector architecture with improved management capabilities. -- **Connector Headers:** Support for custom headers and server_url configuration. -- **Enhanced Tool Picker:** Improved tool selection with better filtering and search. - -## Improvements: - -- **Connected Connector Page:** Redesigned connector details page with better usability. -- **Pending Connectors:** Disabled pending connectors to prevent configuration errors. - -## Bug Fixes: - -- **Connector Display:** Fixed connector description and display issues. -- **Tool Selection:** Resolved tool picker panel bugs and selection state issues. - - - - - -## New Features: - -- **OIDC Parent Accounts:** Support for OIDC parent account authentication. -- **Passwordless Login:** Simplified authentication with passwordless options. -- **SecretsManager Integration:** Enhanced security with AWS SecretsManager authentication. - -## Improvements: - -- **SSO Configuration:** Improved SSO setup and configuration UI. -- **OAuth2 Scopes:** Added readonly scopes for better access control. -- **Login UI:** Enhanced authentication interface with better error messaging. - -## Bug Fixes: - -- **User Provisioning:** Fixed user provisioning to assign member role instead of admin by default. -- **Login Flow:** Resolved login via URL enforcement and redirect issues. - - - - - -## New Features: - -- **Markdown to PDF:** Comprehensive markdown-to-PDF conversion with public static URLs. -- **Advanced PDF Styling:** Enhanced styling with improved line spacing, fonts, and table formatting. -- **DejaVu Sans Font:** Integrated DejaVu Sans font for better international character support. - -## Improvements: - -- **PDF Table Formatting:** Improved table rendering with proper headers and borders. -- **Link Handling:** Better link rendering and word-wrapping in generated PDFs. -- **wkhtmltopdf Optimization:** Fine-tuned PDF generation engine for better performance. - -## Bug Fixes: - -- **PDF Generation:** Fixed multiple PDF generation edge cases and formatting issues. -- **Character Encoding:** Resolved special character and encoding problems in PDFs. - - - - - -## New Features: - -- **Code Interpreter:** Integrated code interpreter for executing code within agents. -- **AI Function Generation:** AI-powered custom function generation with expected output prediction. -- **Enhanced Function Editor:** Improved function editing experience with better syntax highlighting. - -## Improvements: - -- **Generate with AI Button:** Quick access to AI-powered function generation. -- **Function Settings:** Enhanced function configuration options and settings panel. -- **Action Routes:** Improved action routing and editor functionality. - -## Bug Fixes: - -- **Function Editor:** Fixed editor state and saving issues. -- **Custom Actions:** Resolved custom action execution and configuration bugs. - - - - - -## New Features: - -- **GPT-5 Support:** Added support for GPT-5 models with temperature controls. -- **Nvidia LLM Provider:** Integration with Nvidia LLM services and Nvidia Nemo. -- **Custom LLM Keys:** BYOL (Bring Your Own License) support for custom model keys. - -## Improvements: - -- **LLM Key Management:** Enhanced UI for managing and configuring LLM provider keys. -- **Bedrock Provider:** Improved AWS Bedrock integration and error handling. -- **Model Selection:** Better model selection interface with provider-specific options. - -## Bug Fixes: - -- **Provider Configuration:** Fixed LLM provider configuration and key validation issues. -- **Model Loading:** Resolved model loader and initialization bugs. - - - - - -## New Features: - -- **New Pricing UI:** Redesigned pricing interface with transparent tier information. -- **Budget Caps:** Set budget limits to control resource usage and costs. -- **Builder Seats Management:** Manage team builder seats and permissions. -- **Tool Duration Tracking:** Track execution time and resource usage per tool. - -## Improvements: - -- **Resource Monitoring:** Enhanced container usage tracking and cleanup mechanisms. -- **Usage Metrics:** Total execution duration metrics and detailed analytics. -- **Contact Sales Integration:** Seamless integration with sales team for enterprise pricing. - -## Bug Fixes: - -- **Container Cleanup:** Fixed agent container cleanup for hanged assets. -- **Metrics Aggregation:** Resolved metrics collection and aggregation issues. - - - - - -## New Features: - -- **Enhanced Webhook Endpoints:** Webhook endpoints with agent_id in URL paths for better routing. -- **Static Webhook Triggers:** Static trigger endpoints with POST method support. -- **Webhook Tester Modal:** Agent Webhook Tester with file upload capabilities. - -## Improvements: - -- **Async Webhook Invocation:** Improved webhook handling using xpander-sdk for better performance. -- **Form Data Support:** Added application/x-www-form-urlencoded support for webhooks. -- **Webhook Output:** Enhanced structured output and response handling. - -## Bug Fixes: - -- **Webhook Configuration:** Fixed webhook modal layout and configuration issues. -- **Validation:** Resolved webhook validation and curl generation bugs. - - - - - -## New Features: - -- **Complete SDK Refactor:** Major SDK restructure with improved architecture, new agent columns, and enhanced performance. -- **Slack Bots Integration:** Comprehensive Slack bot functionality with auto-engage features, conversation starters, and app distributions. -- **End Client Authentication:** New authentication system with improved security and performance optimizations. -- **AWS Marketplace Integration:** Full integration with AWS Marketplace for seamless deployment and billing. -- **Custom Workers & Kubernetes:** Kubernetes cluster support for custom workers with advanced logging and monitoring capabilities. - -## Improvements: - -- **Agent Versioning System:** Complete agent versioning with draft handling and deployment management. -- **Webhook System Overhaul:** Organization-level API keys and enhanced webhook functionality. -- **Knowledge Base Enhancements:** Advanced CRUD operations, OCR support, and improved document processing. -- **Performance Optimizations:** Significant performance improvements across agent workers and API responses. - -## Bug Fixes: - -- **Memory Management:** Fixed memory leaks and improved garbage collection in long-running sessions. -- **Authentication Issues:** Resolved various authentication and authorization edge cases. -- **UI/UX Improvements:** Fixed multiple interface issues and improved user experience. - - - - - -## New Features: - -- **Neon Database Integration:** Multi-tenant database integration with secure vault storage per tenant. -- **LinkedIn API Updates:** Comprehensive LinkedIn API controller with expanded endpoint coverage. -- **Static File Upload System:** Public CDN upload functionality for static files and assets. -- **Image Generation Multi-turn:** Enhanced OpenAI image generation with multi-turn conversation support. - -## Improvements: - -- **Supabase Migration:** Migrated to async Supabase client for improved performance and reliability. -- **Chainlit Enhancements:** Better cookie handling, empty state fixes, and conversation starters. -- **Agent Builder UI:** Improved agent builder interface with better versioning and status management. - -## Bug Fixes: - -- **Form Submission:** Fixed form handling and submission issues across the platform. -- **Agent Status:** Resolved agent status synchronization and draft handling issues. - - - - - -## New Features: - -- **CSV File Support:** Added comprehensive CSV file processing and handling capabilities. -- **AWS Assume Role Support:** Enhanced AWS integration with assume role functionality for improved security. -- **Default API Keys:** Implemented default API key management system for streamlined setup. - -## Improvements: - -- **Slack Bot Performance:** Enhanced auto-engage functionality with rate limiting and improved context handling. -- **Agent Performance:** Optimized agent worker implementation for better resource utilization. -- **API Security:** Improved authentication parsing and AWS credentials handling. - -## Bug Fixes: - -- **Basic Authentication:** Fixed basic auth parsing issues. -- **AWS Credentials:** Resolved AWS credentials configuration problems. -- **Thread Management:** Fixed thread mapping and context issues in Slack integrations. - - - - - -## New Features: - -- **Mintlify Search Integration:** Added Mintlify search functionality for improved documentation access. -- **PR Title Validator:** Implemented automated PR title validation system. -- **Agent Import System:** Internal agent import capabilities for streamlined deployment. - -## Improvements: - -- **Agent List Performance:** Optimized agent list handling for organizations with 1000+ agents. -- **Error Handling:** Better error handling across various platform components. -- **Code Quality:** Enhanced code quality with improved testing and validation frameworks. - - - - - -## New Features: - -- **OpenTelemetry Integration:** Comprehensive observability and monitoring with OpenTelemetry. -- **Custom Deployment Versioning:** Support for deploying specific versions with custom configurations. -- **Preflight Testing:** Build preflight checks to ensure deployment reliability. - -## Improvements: - -- **Resource Allocation:** Optimized Kubernetes resource allocation and pod lifecycle management. -- **Build System:** Enhanced build system with better dependency management. -- **Deployment Pipeline:** Improved deployment pipeline with better error handling and rollback capabilities. - - - - - -## New Features: - -- **Enhanced Webhook System:** Improved multi-file upload support with better handling of large batch files for document processing agents. -- **Secure File Access:** Added presigned URLs for file access with 30-day validity period. - -## Improvements: - -- **Documentation Updates:** Enhanced documentation with clear examples for file processing workflows. -- **Performance Optimization:** Optimized large batch file handling for improved agent performance. - -Read more here: http://docs.xpander.ai/docs/05-human-interfaces/05-webhooks - - - - - -## New Features: - -- **Model Context Protocol (MCP) Support:** Added native support for MCP across all agentic interfaces. -- **Cross-Provider Compatibility:** Enhanced compatibility with standardized MCP implementations. - -## Improvements: - -- **Agent Performance:** Improved agent performance with optimized MCP message handling. - - - - - -Read more here: http://docs.xpander.ai/docs/05-human-interfaces/04-mcp - - - - - -## New Features: - -- **Extended LLM Provider Support:** Added support for latest model versions across multiple providers. - -## Improvements: - -- **Response Latency:** Improved response latency for high-volume agent deployments. - -## Bug Fixes: - -- **Memory Management:** Fixed memory management issues in long-running sessions. - - - - - -## New Features: - -- **Agent-to-Agent Communication:** Added support for direct communication between agents. -- **Cross-Provider Compatibility:** Updated message format compatibility across providers. - -## Improvements: - -- **Error Handling:** Enhanced error handling for network timeouts during tool execution. - -## Bug Fixes: - -- **UI Rendering:** Fixed rendering issues in the agent configuration panel. - - - - - -## New Features: - -- **Agent Template Gallery:** Released template gallery for faster development workflows. -- **Environment Variables:** Added configuration support for environment variables. - -## Improvements: - -- **Memory Efficiency:** Improved memory efficiency for large context windows. -- **Schema Validation:** Enhanced validation for custom tool schemas. - - - - - -## New Features: - -- **Claude Model Support:** Added support for latest Claude models. -- **Python SDK Examples:** Released new enterprise use case examples. - -## Improvements: - -- **Tool Execution:** Improved performance with parallel processing capabilities. - -## Bug Fixes: - -- **Tool Extraction:** Fixed issues with certain response formats. - - - - - -## New Features: - -- **Unit Testing Framework:** Added framework for agent behavior validation. -- **Performance Monitoring:** Released dashboard for agent performance tracking. - -## Improvements: - -- **Tool Coordination:** Enhanced execution coordination between multiple agents. -- **Documentation:** Improved guides for custom tool development. - - - - - -## New Features: - -- **Mixtral Model Support:** Added support for additional Mixtral models. -- **Structured Logging:** Implemented enhanced logging with structured output. - -## Improvements: - -- **Cross-Provider Compatibility:** Enhanced compatibility for tool formats. - -## Bug Fixes: - -- **Serialization:** Fixed issues with nested tool responses. - - - - - -## New Features: - -- **Debugging Tools:** Released comprehensive debugging tools for agent development. -- **File Attachment API:** Added support for file attachments via API. - -## Bug Fixes: - -- **Memory Initialization:** Fixed issues with provider switching scenarios. - - - - - -## New Features: - -- **Agent Metrics Dashboard:** Released comprehensive metrics and analytics dashboard. -- **Runtime Tool Registration:** Added capabilities for dynamic tool registration. - -## Improvements: - -- **Error Reporting:** Enhanced reporting with context preservation. -- **Message Handling:** Improved format handling for all providers. - - - - - -## New Features: - -- **OpenAI Model Support:** Added support for latest OpenAI models. -- **Python Decorators:** Released decorator-based tool registration system. - -## Improvements: - -- **Authentication:** Enhanced with automatic token refresh capabilities. - -## Bug Fixes: - -- **Tool Execution:** Fixed timeout handling issues. - - - - - -## New Features: - -- **Memory Management:** Enhanced system with retention controls and user-specific isolation. -- **Multi-User Support:** Improved state management for multi-user scenarios. - -## Improvements: - -- **Documentation:** Released guides for edge deployment scenarios. - - - - - -## New Features: - -- **Multimodal Capabilities:** Added support for multimodal agent interactions. -- **Document Processing:** Released comprehensive examples and templates. - -## Improvements: - -- **Security:** Enhanced handling of sensitive data. -- **Telemetry:** Improved agent execution monitoring and analytics. - - - - - -## New Features: - -- **Initial Release:** Official launch of xpander.ai platform. -- **LLM Integration:** Support for OpenAI, Claude, and Gemini LLM providers. -- **Memory Management:** Basic memory management and tool execution framework ([SDK Agent Reference](/API reference/agents/index)). -- **Authentication:** Simple authentication and user management system. - - - - - -## New Features: - -- **Ollama Support:** Added support for local model inference via Ollama. -- **Agent State Management:** Released beta version of comprehensive state management. - -## Improvements: - -- **Error Handling:** Improved handling for tool executions. -- **Documentation:** Enhanced with quick start guides ([docs/01-get-started/01-index.mdx](/user-guide/index)). - - - - - -## New Features: - -- **FriendliAI Integration:** Launched support for FriendliAI with Claude models. -- **Dynamic Tool Discovery:** Added mechanism for automatic tool discovery. - -## Improvements: - -- **Performance:** Enhanced performance for high-volume deployments. -- **Examples:** Released extended integration pattern examples. - - - - - -## New Features: - -- **Streaming Responses:** Added support for streaming from all providers. -- **Python Client:** Released new client with simplified API. - -## Improvements: - -- **Tool Compatibility:** Enhanced cross-provider tool format compatibility. -- **Memory Consistency:** Improved consistency across multi-turn conversations ([SDK Agent Reference](/API reference/agents/index)). - - - - - -## New Features: - -- **LangChain Integration:** Added comprehensive LangChain support. -- **Tool Format Conversion:** Released automatic conversion utilities. - -## Improvements: - -- **Memory Initialization:** Enhanced with custom instructions support. - - - - - -## New Features: - -- **NVIDIA NIM Support:** Added support for NVIDIA NIM models. -- **Persistent Storage:** Enhanced agent memory with storage options. - -## Improvements: - -- **Error Handling:** Improved handling for rate limiting and quotas. -- **Examples:** Released multi-step task execution examples. - - - - - -## New Features: - -- **Multi-Provider Switching:** Support for switching providers within same session. -- **Provider Adapter Pattern:** Released simplified integration pattern. - -## Improvements: - -- **Tool Execution:** Enhanced framework with parallel processing. -- **Documentation:** Improved with provider-specific best practices. - - - - - -## Improvements: - -- **Message Handling:** Enhanced format handling across providers. -- **Tool Extraction:** Improved reliability with explicit provider specification. -- **Documentation:** Released extended memory management guides. - - - - - -## New Features: - -- **Automatic Format Conversion:** Added message format conversion between providers. -- **Python SDK:** Released with expanded provider support. - -## Improvements: - -- **Error Reporting:** Enhanced with provider-specific details. -- **Schema Validation:** Improved tool schema validation for better compatibility. - - - - - -## New Features: - -- **Alpha Release:** Initial alpha version with basic OpenAI integration. -- **Tool Calling:** Support for simple tool calling and execution ([SDK Tools Reference](/API reference/tools/index)). -- **Memory Management:** Initial capabilities ([SDK Agent Reference](/API reference/agents/index)). -- **Documentation:** Basic documentation and examples ([docs/01-get-started](/user-guide)). - - - -> Note: Current SDK version is v1.47.10 as of this documentation update. +--- \ No newline at end of file