LLM Generative AI Page Editor - PHP & JS

I'm currently building a project where a lightweight JavaScript SDK is embedded into client websites, allowing them to modify their pages through a side-panel interface. The next phase is to evolve this panel into a conversational AI experience.

The goal is to enable users to input natural language instructions such as “add an interactive slider at the top” or “change all headings to a dark blue serif font,” with the system intelligently interpreting the request, identifying the site’s existing design system, generating the necessary HTML/CSS/JS, and applying the changes to the DOM in real time.

The scope of supported actions includes:
- Creating new elements (e.g. interactive sliders, image galleries, single and multi-step forms)
- Modifying existing elements
- Removing elements
- Updating styles (colours, typography, layout)
- Editing content
- Injecting JavaScript behaviours and event handling
- Other types of modifications

A key requirement is that all generated output must align with the site’s existing design tokens to ensure visual consistency.

What I’m looking for:

- Backend (PHP 8)
- A server-side endpoint that brokers requests to an LLM (e.g. OpenAI, Claude)
- Clean, framework-free implementation in vanilla PHP
- Structured request/response handling for reliability and extensibility

Frontend (JavaScript SDK)
- Utilities to extract relevant design context (CSS variables, computed styles, key layout patterns)
- Efficient context packaging to minimise token usage
- Safe DOM injection of AI-generated output

Reliability & Safety
- Validation and fallback mechanisms to prevent malformed AI responses from breaking the page
- Graceful degradation when outputs are incomplete or invalid

Implementation
- Clear setup instructions so this can be easily integrated into any site already running the SDK
- An MVP flow: user prompt → model request → validated response → live DOM update

I already have a working version, but it lacks consistency, doesn’t properly leverage the existing design system, and has some stability issues. I’m looking to refine this into a more robust foundation and continue iterating on it long term.

I’m happy to share the current implementation and collaborate on improving the architecture, model strategy, and overall reliability.