Claude Agent SDK vs OpenAI API
These two do quite different things, so neither is a direct alternative to the other.
Claude Agent SDK Anthropic
The agent loop behind Claude Code as a TypeScript and Python library, with tools, skills, MCP and subagents.
VisitOpenAI API OpenAI
GPT models for text, vision, images, audio and realtime voice, plus the Agents SDK.
VisitSide by side
| Property | Claude Agent SDK | OpenAI API |
|---|---|---|
| Type | Product | Product |
| Category | AI agents and automation | AI models and APIs |
| Made by | Anthropic | OpenAI |
| Pricing | Pay per use | Pay per use |
| Open source | No | No |
| API | Yes | Yes |
| Platforms | API | API |
| Startup | Yes | Yes |
Features
Only Claude Agent SDK
- agent framework
- mcp
- skills
- multi-agent
Both
None
Only OpenAI API
- llm api
- reasoning
- image generation
- voice
- embeddings
- agents