ConstraintThe product problem
Standalone chat/LLM API service (OpenAI, Anthropic, Gemini, Alibaba, Azure-OpenAI, open-source) with streaming, structured JSON output, tools, cost estimation, keyword volume, text-to-image and file upload. The engineering challenge is to turn that scope into a legible system with explicit inputs, dependable workflow boundaries, and an outcome that can be inspected and maintained.
SystemThe architecture decision
The reviewed implementation routes message / context through conversation & tool orchestration, crosses model, knowledge & business apis where required, and produces contextual response / action.
OutcomeThe operating result
Multi-Model LLM Gateway is included as documented engineering work. Its source structure, technology stack, and functional flow are presented here even though no verified public deployment is currently available.