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ā€¢2 min read

200K Context Window Is Insane

AIanthropictech

anthropic released claude 2.1 and the headline feature is ridiculous: 200,000 tokens of context.

to put that in perspective: that's about 500 pages of text. you can feed an entire book into the model.

why this matters

context window = how much the model can "remember" during a conversation.

gpt-4 has 8k or 32k depending on version. enough for a long essay.

200k means entire codebases. entire documents. entire conversations that span days.

the use cases multiply:

  • "summarize this research paper" ā†’ "summarize these 20 research papers and compare them"
  • "help me debug this function" ā†’ "understand my entire codebase and help me design a new feature"
  • "what was i asking about earlier?" ā†’ works because "earlier" might be hours ago

my experiments

i dumped my entire thesis draft (so far) into claude 2.1 and asked questions about it.

it worked. it understood the context. it remembered details from the introduction while answering about the methodology section.

this feels like a different kind of tool. less "helpful assistant" and more "temporary collaborator who has read everything you've written."

the technical implications

bigger context = more compute = more expensive. i'm curious how they're making this work efficiently.

there's a lot of research on efficient attention, and anthropic must be using something clever. the original attention mechanism scales quadratically with context length, which should make 200k tokens prohibitively slow.

whatever they're doing, it's impressive.

anthropic keeps impressing me

here's what i notice about anthropic's approach:

they're not just racing for benchmarks. they ship features that feel thoughtful:

  • longer context for complex tasks
  • focus on reducing hallucinations
  • emphasis on being honest about uncertainty

compare to openai, which seems more focused on raw capability and speed-to-market.

both approaches have merit. but anthropic's philosophy resonates with me more.

the bias disclosure

i should acknowledge: i'm becoming an anthropic fan. this might color my perception.

but also: i've used both extensively and claude just... works better for how i think? less confident BS, more honest hedging.

your mileage may vary.

fed my entire research notes folder into claude 2.1. asked for insights. it found connections i missed. slightly terrified by this.