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mh- • today at 7:22 PM • 1 reply • view on HN

This is interesting, because if I start a fresh session of Claude Code right now and run /context, I see the following:

   Opus 4.8 (1M context)
   claude-opus-4-8[1m]
   23k/1m tokens (2%) 

   Estimated usage by category
   System prompt: 3.9k tokens (0.4%)
   System tools: 13.9k tokens (1.4%)
   Custom agents: 235 tokens (0.0%)
   Memory files: 28 tokens (0.0%)
   Skills: 4.9k tokens (0.5%)
   Messages: 8 tokens (0.0%)
   Compact buffer: 3k tokens (0.3%)
   Free space: 974k (97.4%)
4k tokens is 15-20kB. I'd ask you to paste that into a gist, but it might have sensitive data in it, because I suspect what you're seeing is not just the system prompt.

Replies

mft_ • today at 7:53 PM

Apologies, you're right - I used imprecise terminology. The entire initial JSON structure that was sent from Claude Claude to the LLM at the start of a session was 162k. This included the system prompt together with a list of tools (some with very extensive explanations), MCP server details, etc.

I was simply supporting the article's data - their reported 33k tokens is probably roughly 150-165k.

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