Add use_llm support to marker_server for OpenWebUI integration

[bankjaneo]

Summary

Add use_llm support to marker_server API to enable OpenWebUI's "Use LLM" toggle for enhanced PDF processing with Large Language Models.

Changes

• Add use_llm: bool = False field to CommonParams model in marker/scripts/server.py
• Update /marker/upload endpoint to accept use_llm form parameter
• LLM service configuration (API keys, models) is read from environment variables set in docker-compose

How It Works

When OpenWebUI sends "use_llm": true in the request:

1. The server accepts and passes the use_llm flag through the conversion pipeline
2. ConfigParser.get_llm_service() checks if use_llm=True and returns the configured LLM service
3. The converter uses the LLM service for higher quality OCR processing

Supported LLM Providers

• Gemini (default)
• OpenAI
• Claude (Anthropic)
• Ollama (local)
• Vertex AI
• Azure OpenAI

Environment Configuration

Users configure LLM credentials in their docker-compose.yml:

environment:
  - USE_LLM=true
  - OPENAI_API_KEY=your_key_here
  - OPENAI_MODEL=gpt-4o-mini

Or with other providers:

• Gemini: GEMINI_API_KEY, GEMINI_MODEL_NAME
• Claude: CLAUDE_API_KEY, CLAUDE_MODEL_NAME
• Ollama: OLLAMA_BASE_URL, OLLAMA_MODEL

Testing

The feature can be tested:

1. Via OpenWebUI by toggling the "Use LLM" option (with credentials configured)
2. Via API: POST /marker/upload with use_llm=true form parameter
3. Via JSON: POST /marker with {"use_llm": true, ...}

🤖 Generated with Claude Code

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❌ @claude
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