Stored locally in your browser only. Sent only to Anthropic's API. Get a key at console.anthropic.com
FAST uses Haiku 4.5 — cheapest, ~10-15s, ~$0.01-0.03 per report. DEEP uses Sonnet 4 — better reasoning, ~25-40s, ~$0.05-0.15 per report. Prompt caching enabled on both.