OpenAI GPT
model-providerOpenAI's GPT family (GPT-4o, GPT-4, o1, o3) defined the modern LLM landscape. GPT models pioneered function calling, the Assistants API, and many patterns that became industry standards.
The ecosystem around GPT is the largest in the industry — thousands of plugins, integrations, and tools work with OpenAI's API format. Most agent frameworks default to OpenAI-compatible APIs, making GPT the most broadly supported model family.
GPT-4o offers strong multimodal capabilities (text, vision, audio), while the o-series models provide enhanced reasoning. The Assistants API adds built-in code execution, file handling, and retrieval.
Key Features
- •Pioneered function calling pattern
- •Assistants API with built-in tools
- •Multimodal (text, vision, audio, image gen)
- •Fine-tuning and batch API
- •Largest third-party ecosystem
Pros
- +Broadest compatibility and ecosystem
- +Strong code generation
- +Mature function calling
- +Multiple model tiers for cost optimization
Cons
- −Shorter context than Claude (128K vs 200K)
- −Less literal instruction following
- −Ecosystem lock-in concerns