Prompt
What should I use if I need prompt templates and tool use?
Latest observation
Oct 9, 2026
OpenAI APIWeb search: off
If you need prompt templates + tool use, the best fit is usually LangChain.
Why LangChain?
- Prompt templates: easy to define, reuse, and parameterize prompts
- Tool use: built-in support for calling functions, APIs, retrievers, and agents
- Agent workflows: useful if the model needs to decide when to use tools
- Integrations: lots of support for vector DBs, LLM providers, and external systems
Good alternatives
- Semantic Kernel: strong if you want a more structured, enterprise-friendly approach, especially in .NET / Python
- LlamaIndex: great if your main need is RAG / data retrieval, with some tool use support
- OpenAI SDK directly: best if you want the simplest setup and only need basic templating/tool calling without a larger framework
Rule of thumb
- General-purpose agent + tool orchestration → LangChain
- RAG-heavy app → LlamaIndex
- Lightweight, custom solution → OpenAI SDK directly
- Microsoft ecosystem / structured orchestration → Semantic Kernel
If you want, I can recommend one based on your language stack:
- Python
- JavaScript/TypeScript
- .NET
- something else