Credits
Reading the archive is always free. Credits are only needed for the AI chat function.
Every day, 50 free chat queries are available to all visitors — first come, first served. Credits unlock unlimited access beyond that daily limit.
Why is the chat charged?
Every chat query searches the multi-million-word knowledge base and generates a synthesised answer using a live AI model (Claude by Anthropic). Each query incurs a real API cost — we charge a small credit fee to cover those costs and keep the service running. Browsing, reading, and searching the archive will always be free. The daily free allowance is capped site-wide to control costs; credits remove that cap for serious researchers.
Query types
Model: Haiku
Fast factual answers. Ideal for dates, names, brief summaries.
Model: Sonnet
Analytical responses with full context. The default query type.
Model: Sonnet (extended)
Comprehensive synthesis across multiple documents and themes.
Credit Packs
Credits expire 6 months from purchase. All prices in USD.
Starter
Try it out
100 credits
- ~100 Quick queries
- ~33 Standard queries
- ~20 Deep queries
Buy multiple times to stack credits
Explorer
Most flexible
500 credits
- ~500 Quick queries
- ~167 Standard queries
- ~100 Deep queries
Buy multiple times to stack credits
Researcher
Most popular
1,500 credits
- ~1,500 Quick queries
- ~500 Standard queries
- ~300 Deep queries
Buy multiple times to stack credits
Scholar
Best value
5,000 credits
- ~5,000 Quick queries
- ~1,667 Standard queries
- ~1,000 Deep queries
Buy multiple times to stack credits
Credits expire 6 months from purchase · Non-refundable · FIFO consumption
Not ready to buy credits?
You can still use the 50 free daily queries, read every document in the archive for free, or watch the video series on YouTube — no credits, no account needed.