LLM Providers & APIs Guide: OpenAI, Claude & Gemini (Models, Endpoints, Usage)

2026-04-26 · Source: LLM on Medium · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Software Development & Engineering · Depth: Novice, quick

Summary

This guide serves as a practical mini-wiki for major Large Language Model (LLM) providers, including OpenAI, Anthropic (Claude), and Google (Gemini). It consolidates essential information on their models, API endpoints, and usage details, aiming to facilitate quick exploration and development on these platforms. OpenAI, a prominent provider, offers models like GPT-5.4 Mini, GPT-5.4 Nano, and GPT-4o Mini for basic text generation, alongside GPT Image 2 for image generation. The document points to OpenAI's official API documentation for more comprehensive model details. This resource is designed to streamline the process of understanding and implementing various LLM capabilities.

Key takeaway

For AI Engineers evaluating LLM platforms, this guide provides a consolidated overview of OpenAI, Anthropic, and Google's offerings. You should consult the listed models and API endpoints to quickly prototype applications or integrate specific generative capabilities into your projects, saving time on initial research.

Key insights

Major LLM providers offer diverse models and APIs for text and image generation.

Principles

• Consolidate API information for efficiency
• Prioritize practical application details

In practice

• Explore OpenAI's GPT-5.4 Mini for text
• Utilize GPT Image 2 for image tasks

Topics

• LLM Providers
• OpenAI API
• Anthropic Claude
• Google Gemini
• Generative AI Models

Best for: AI Engineer, Machine Learning Engineer, NLP Engineer

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Editorial summary, takeaway, and curation by AIssential. Original article published by LLM on Medium.