Cut Claude API Costs 80% by Splitting Vision and Reasoning Tasks

The Problem That Forced the Question

I was building an ingestion pipeline for a personal knowledge system—drop in a PDF, get structured OKF-format concept articles out the other side. Anthropic's vision models are genuinely good at reading image-only PDFs (scanned docs, Medium exports printed to PDF), so I wired them into my OCR layer.

Then I looked at the cost estimate for my sample: a 26-page image-only PDF. Running everything through claude-opus-4-8 would cost $1.00–$1.30 for a single document. Scale that to a few dozen docs and suddenly my personal knowledge base has a real operational cost.

The fix was obvious once I thought about it—but I hadn't thought about it.

The Insight: OCR Is Transcription, Not Reasoning