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ctxprobe
confirmedPython · CPUInference & servingJuly 5, 2026
the question
How does retrieval accuracy degrade with context length and where the answer sits?
what came out
On a real 32k-window model, retrieval degrades past ~17k and shows a clean lost-in-the-middle U-shape -- compounding to 0.30 at 30k-middle versus 0.90 at the start. Length and burial stack.
method & receipts
- Result: confirmed
- Reproducible — one script re-runs the whole thing from scratch.
- Machine-readable claims — every reported number, in a checkable file.
- Tested — a correctness/benchmark suite ships alongside the code.
→ read the code and re-run it
github.com/v-code01/ctxprobe