Best AI tools for Large Language Models (LLMs) in 2025

OpenAI's GPT-5.1 is an upgraded version of ChatGPT that introduces two new models - Instant and Thinking - with improved conversational abilities, adaptive reasoning, and customizable personality settings.

SearchGPT is an AI-powered search prototype by OpenAI that provides fast, conversational answers with clear sources using GPT models.

ContextGem is a free, open-source LLM framework that simplifies structured data and insights extraction from documents with minimal code through powerful built-in abstractions and automated features.

AI CLI is an open-source command-line interface tool that brings AI capabilities directly to your terminal, allowing you to interact with various AI models like OpenAI's GPT and Anthropic's Claude through simple commands.

UFO² is Microsoft's next-generation Desktop AgentOS that transforms natural-language requests into automatic, reliable, multi-application workflows on Windows, combining UI automation, native API integration, and multi-agent coordination.

VoltAgent is an open-source TypeScript framework that provides modular building blocks and built-in observability for creating and orchestrating AI agents, bridging the gap between no-code limitations and from-scratch complexity.

The Hierarchical Reasoning Model (HRM) is a brain-inspired AI architecture that achieves exceptional reasoning capabilities with only 27 million parameters, using two interdependent recurrent modules for abstract planning and detailed computations.

Kuzco is a powerful Swift package that enables local Large Language Model (LLM) inference directly in iOS and macOS apps, built on llama.cpp with zero network dependency for privacy-focused AI integration.

UTCP (Universal Tool Calling Protocol) is an open standard protocol that enables AI agents to directly call any native API endpoint across different communication protocols without requiring middleware or wrapper servers.

MulmoCast Vision is an AI-powered tool that automatically generates professional presentation slides through LLMs via Model Context Protocol (MCP), featuring 80+ business-oriented templates for various corporate needs.

An open-source Chrome extension that integrates AI models like Gemini, GPT, and Claude directly into your browser for tasks like chat assistance, screenshot analysis, and multi-model response comparison.

nanochat is an open-source, full-stack implementation of a ChatGPT-like language model that can be trained for just $100 in 4 hours on an 8XH100 GPU node, providing a clean, minimal, and hackable codebase with complete pipeline from tokenization to deployment.