Capture the lesson so future-ATLAS does not pay the same debugging cost twice.

When to write an entry

Write one — without being asked — when either is true:

Boss had to step in. A bug or mistake ATLAS could not solve alone; Boss's guidance is what cracked it.
Aha moment after a long hunt. A debugging session that ran long and ended in a non-obvious realization.

Skip routine fixes. The bar is surprise: would this genuinely save someone — likely future-ATLAS — from a hard time? If the cause was obvious in hindsight to anyone, it is not worth an entry. Apply the same high-entropy filter as NOTES.md: record what is surprising, not what is expected.

Where

One file per lesson: docs/learning-from-mistakes/<kebab-case-slug>.md. The slug names the problem, so the folder is self-indexing — e.g. stale-closure-in-useeffect.md, timezone-off-by-one-on-date-parse.md.

Format

Keep it brief — important information only. Four short sections: