Understand what you're reading.

Select a sentence on any page or PDF. Focal explains it using the whole document, checks whether it's actually true, and tells you if the piece is worth your time at all.

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Attention Is All You Need — arxiv.org, PDF

We propose a new simple network architecture, the Transformer, based solely on attention mechanisms, dispensing with recurrence and convolutions entirely.

✦ Explain✓ Validate

Answered from this document

Earlier models read a sentence in order, one word at a time, so each step waited on the last. This one drops that: every word looks at every other word at once. That is what the paper calls multi-head self-attention in §3.2.

Grounded in §1 and §3.2 — not from the model's memory.

Three things it does

Explain it, check it, or skip it.

Each one answers a different question you have while reading. Nothing else is in the way.

Explain

Reads the whole page before it answers, so “this method” and “as shown above” resolve to the right thing. It answers from the document or says it can’t — it won’t fill the gap from memory.

You selected

…dispensing with recurrence entirely.

Answer cites §3.2 · 94 words

Validate

Fact-checks the claim you highlighted against the live web and lists its sources. Highlight a heading or half a sentence and it says so, instead of inventing a verdict for something that isn’t a claim.

Checked against 3 sources

The 3.57% figure is the ensemble error, not single-model.

2 sources cite the single-model number instead.

Worth reading?

A verdict before you commit twenty minutes — with the claims it found and the evidence behind each one. Deliberately not a score out of ten, because you can’t check a score.

Verdict

Worth reading

4 substantive claims · ~11 min · covers ground you haven’t read

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Where your reading goes

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Never involved: a Focal server, an account, analytics, or any page you didn't ask about.

Pricing

Free while it's this young.

The extension is free and you pay OpenAI for what you use. A hosted plan is coming for people who'd rather not manage a key.

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Hosted

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