I Spent 1 Billion Tokens Making a Real Chip with AI — and Found Its True Limits

I Spent 1 Billion Tokens Making a Real Chip with AI — and Found Its True Limits TL;DR: This is not "I prompted an AI to make a chip." It's the consolidated retrospective of two month-long projects — a SHA-256 crypto accelerator driven end-to-end from RTL to a 10-item signoff on an open-source EDA stack, then integrated into a real SoC. Two AI agents plus one human, roughly 1 billion tokens across both projects. The chip passed signoff. But the most valuable output wasn't silicon — it was a clear map of where AI's ability actually ends, and a repeatable method for keeping it honest. And right now, I need one small favor from you (at the end). What This Series Is (and Is Not) I've written two deep dives covering the mechanics of these projects: The core — how an LLM agent carried a SHA-256 core from RTL to GDSII, through 10 industrial signoff checks on Yosys / OpenROAD / Magic / Netgen / iverilog. The integration — how that same core was embedded