The AI tools stack

AI21 Labs

Model platform and studio for AI21's Jamba hybrid SSM-Transformer models with long context and an API.

Allen Institute for AI (Ai2)

Free research demo to chat with Ai2's fully-open OLMo and Tülu models.

Baseten

Production inference platform for deploying open-source and custom AI models — optimized runtimes for LLMs, TTS, transcription, and image generation with cross-cloud high availability.

Cerebras Systems

Wafer-scale-engine inference service offering some of the fastest token throughput available, with a free demo chat.

Character Technologies

Chat platform where users create and converse with custom AI characters — historical figures, fictional personas, or invented experts.

OpenAI

The most widely-used AI chat assistant with image, voice, and a broad ecosystem of plugins and custom GPTs.

ChatPRD

AI assistant for product managers — turns rough ideas into structured PRDs, generates user stories, and critiques specs against PM best practices.

Anthropic

A general-purpose chat assistant known for nuanced reasoning, careful writing, and very long context handling.

Cohere

Enterprise chat assistant grounded in your own documents, with strong RAG, citations, and workplace privacy controls.

DeepSeek

Chinese open-weight model with strong reasoning and coding capabilities at very low cost.

Doximity

Free HIPAA-compliant AI for verified U.S. physicians — drafts clinical notes, prior auth letters, and patient communications inside Doximity's workflow.

Duolingo

Premium tier of Duolingo with AI-powered Roleplay (conversation practice) and Explain My Answer (grammar explanations from a virtual tutor).

Fireworks AI

Fast serverless inference platform with 200+ open models, day-0 support for new releases, fine-tuning and a playground.

Google

Google's multimodal assistant with native integration into Gmail, Docs, Sheets, and the rest of Workspace.

xAI

xAI's assistant with real-time access to X (Twitter) data, useful for tracking live discourse.

Groq

LPU-based inference platform delivering very low-latency token generation for open models, with a free chat playground (GroqCloud).

Harvey

Domain-trained AI built specifically for elite law firms — handles contract review, legal research, drafting, and transactional analysis with citations.

Hippocratic AI

Healthcare-specific LLM platform for patient-facing use cases — chronic care check-ins, post-discharge follow-ups, and triage — with HIPAA-grade safety.

Hugging Face

Free, open-source chat interface that lets you switch between top open-weight models (Llama, Mistral, Qwen, etc.) — no account required for casual use.

Sarvam AI

Chat app from Indian lab Sarvam AI built on its Sarvam 105B model, focused on Indian languages.

Khan Academy

Khan Academy's AI tutor that uses Socratic dialog to guide students through problems instead of handing them answers — covers math, science, humanities, and SAT prep.

Moonshot AI

Chinese chat assistant with extremely long context windows (up to 2M tokens) and a strong agent mode for browsing and tool use.

Mistral

European chat assistant from Mistral with strong multilingual support and a focus on data sovereignty.

Liner

AI answer engine specifically tuned for academic and trustworthy sources, with inline citations and a "Scholar" mode for paper-grounded research.

Proton

Privacy-first chat assistant from Proton where conversations stay encrypted and confidential.

Meta

Meta's consumer assistant powered by the open-weight Llama family, available standalone and integrated across WhatsApp, Instagram, Messenger, and Facebook.

Microsoft

Microsoft's chat assistant available across Windows, Edge, and Microsoft 365 — combines GPT models with deep integration into Word, Excel, Outlook, and Teams.

MiniMax

Chat assistant and model platform with long-context models (up to 1M tokens) and an agent product.

Nebius

Inference platform with a model playground and OpenAI-compatible API for testing and deploying open LLMs.

OpenRouter

Unified OpenAI-compatible API and chat UI that routes requests across 400+ models from 70+ providers with one bill.

Perplexity AI

A search-grounded answer engine that cites sources for every claim, useful when you need verifiable information.

Aleph Alpha

Enterprise chat assistant from German lab Aleph Alpha that answers over uploaded documents and generates deep-research reports.

Inflection AI

Conversational AI tuned for warmth and reflection rather than raw output — designed to help you think through decisions, journal, or just talk something out.

Quora

Single interface to chat with most leading models (Claude, GPT, Gemini, Llama, etc.) plus thousands of community-built bots — pay one subscription, switch freely.

Poolside

Foundation-model company behind the Laguna model family — Laguna M.1 (225B MoE, 23B active) and Laguna XS.2 (33B MoE, 3B active), open-weight models trained for agentic coding and available via OpenAI-compatible API.

Alibaba

Alibaba's open-weight Qwen models in chat form — multilingual, strong at coding and math, with both reasoning and standard modes.

Reka AI

Multimodal chat assistant that reasons over text, images and files in real time, with a separate research/playground app.

Speakeasy Labs

Voice-first AI language tutor — real-time spoken conversation with an AI that corrects pronunciation, suggests vocabulary, and adapts to your level.

Together Computer

Inference and fine-tuning platform serving 200+ open-weight models through an OpenAI-compatible API and a model playground.

Zhipu AI

Free chat assistant and agent powered by the GLM model family, with reasoning and tool-use features.