Show HN: A modern C++20 AI SDK (GPT‑4o, Claude 3.5, tool‑calling)

1 cauchyk 0 6/29/2025, 12:52:42 PM

Hi all,

I’m hacking on new features for the ClickHouse native client and wanted the same “just call the model” ergonomics JavaScript and Python now enjoy. It didn’t exist for modern C++, so I wrote one.

ai‑sdk‑cpp (Apache‑2.0) gives you:

- Unified calls to OpenAI (GPT‑4o) and Anthropic (Claude 3.5) with a single C++20 API. - Streaming, multi‑turn chat, error handling—all std::optional/std::variant, no macros. - Tool calling (function‑calling) so the model can hit real APIs; sync or async, runs in parallel.

The tricky bit: C++ still lacks real reflection, so mapping plain functions → JSON schemas isn’t as automatic as, say, TypeScript decorators. I’d love fresh eyes on that part. Try the examples and tell me where it feels clunky. This is inspired by Vercel's AI SDK [1], and litellm [2].

Repo live here: https://github.com/ClickHouse/ai-sdk-cpp, feedback welcome!

[1] https://github.com/vercel/ai [2] https://github.com/BerriAI/litellm

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Show HN: A modern C++20 AI SDK (GPT‑4o, Claude 3.5, tool‑calling)

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