Pitfall Notes

Real-world engineering pitfalls documented as they happened: symptom, root cause, and verified fix. Calendar math, time zones, CI/CD, LLM apps — every post is a hands-on postmortem from building and running this site, not theory.

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Fable 5 Has a 1M Context Window, So Why Does the Status Line Say 200k? Capture the Data Before You Swap the Tool

Claude Fable 5 officially ships with a 1M-token context window, yet the Claude Code status line kept showing 200k as the denominator. The first instinct — 'let's switch to a better statusline' — was wrong. This postmortem walks through the full debugging process: one line of tee to capture the statusline's stdin, hard evidence that the official field misreports 200000 for new models, and a model-table fix. Plus a general lesson: swapping tools never fixes a broken data source.

llmclaude-code+3

pitfallsAug 14, 20264 min

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