OpenAI Agents SDK vs Semantic Kernel: Agent Frameworks Comparison
Compare OpenAI Agents SDK and Semantic Kernel side by side. Both are tools in the Agent Frameworks category.
Updated March 10, 2026
The short answer
Choose OpenAI Agents SDK if completely free and open-source SDK.
Choose Semantic Kernel if free open-source.
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Quick Comparison
| Category | Agent Frameworks | Agent Frameworks |
| Pricing | — | Open Source |
| Best For | — | Enterprise .NET developers building AI applications on Microsoft infrastructure |
| Website | github.com | learn.microsoft.com |
| Key Features | — |
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| Use Cases | — |
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Pros & Cons: OpenAI Agents SDK vs Semantic Kernel
- +Completely free and open-source SDK
- +Lightweight architecture with minimal learning curve
- +Production-ready from launch with proven enterprise adoption
- +Handles 80 percent of use cases without complexity
- −API usage costs can escalate quickly with complex agent workflows
- −Less suitable for workflows requiring deep customization
- −Tightly coupled to OpenAI ecosystem
- −Simpler than LangGraph which may limit advanced use cases
- +Free open-source
- +Microsoft-backed
- +Multi-language
- −Learning curve
- −Microsoft focus
Pricing: OpenAI Agents SDK vs Semantic Kernel
- · Open-source framework
- · Four core primitives
- · Production-ready
- · Full documentation
- · Model-specific pricing
- · GPT-5.4 from USD 2.50/M tokens
- · Flexible scaling
- · No minimum commitment
- · Core features
- · Advanced features
- · Custom
When to Choose OpenAI Agents SDK vs Semantic Kernel
- Enterprise AI on Microsoft stack
- Copilot-style applications
- Integrating AI into .NET applications
How to Choose a Agent Frameworks Tool
Key criteria to evaluate when comparing Agent Frameworks solutions:
About OpenAI Agents SDK
The OpenAI Agents SDK is a production-ready framework launched in March 2025 as an evolution of OpenAI experimental Swarm project, which was widely adopted by the developer community. The SDK is completely free and open-source, though users pay for actual API usage when utilizing OpenAI hosted models. Built with a lightweight architecture featuring just four core primitives, the SDK makes it immediately accessible to developers familiar with OpenAI ecosystem. The framework requires only a few lines of code to get started and handles 80 percent of agent use cases with minimal overhead. Major companies like Coinbase used the Agents SDK to quickly prototype and deploy AgentKit for crypto wallet interactions. The SDK supports various real-world applications including customer support automation, multi-step research, content generation, code review, and sales prospecting. While the SDK itself is free, costs depend on token usage of the underlying models, with prices varying from USD 2.50 per million tokens for GPT-5.4 and higher. The OpenAI SDK is ideal for rapid development, while alternatives like LangGraph suit complex workflows requiring deep customization.
About Semantic Kernel
Microsoft Semantic Kernel is open-source SDK for building AI applications combining LLMs with programming. Multi-language support.
What is Agent Frameworks?
Developer frameworks and SDKs for building autonomous AI agents with tool use, planning, multi-step reasoning, and orchestration capabilities.
Browse all Agent Frameworkstools →Frequently Asked Questions
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