Short answerA custom replacement has five parts: a model API, retrieval over your files, tools for your Actions, a chat interface and protections like rate limits and secret keys. Official function-calling and SDK docs cover the coding details.
The parts
- Model API: OpenAI, Anthropic or another provider (costs).
- Retrieval: find relevant passages from your files (how it works).
- Tools: your former Actions as tool or function calls. OpenAI's function-calling guide covers JSON-schema function tools.
- Interface: a web chat. The Vercel AI SDK is one official TypeScript library with tool calling and chatbot UI hooks.
- Protections: keep keys on the server, rate-limit, cap length (checklist).
This is a developer project. If you want a scoped plan, request an audit; for a no-code route see no-code vs API.
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Sources
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