lesson-learned

1# Lesson Learned
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3Extract specific, grounded software engineering lessons from actual code changes. Not a lecture -- a mirror. Show the user what their code already demonstrates.
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5## Before You Begin
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7**Load the principles reference first.**
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91. Read `references/se-principles.md` to have the principle catalog available
102. Optionally read `references/anti-patterns.md` if you suspect the changes include areas for improvement
113. Determine the scope of analysis (see Phase 1)
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13**Do not proceed until you've loaded at least `se-principles.md`.**
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15## Phase 1: Determine Scope
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17Ask the user or infer from context what to analyze.
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19| Scope | Git Commands | When to Use |
20|-------|-------------|-------------|
21| Feature branch | `git log main..HEAD --oneline` + `git diff main...HEAD` | User is on a non-main branch (default) |
22| Last N commits | `git log --oneline -N` + `git diff HEAD~N..HEAD` | User specifies a range, or on main (default N=5) |
23| Specific commit | `git show <sha>` | User references a specific commit |
24| Working changes | `git diff` + `git diff --cached` | User says "what about these changes?" before committing |
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26**Default behavior:**
27- If on a feature branch: analyze branch commits vs main
28- If on main: analyze the last 5 commits
29- If the user provides a different scope, use that
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31## Phase 2: Gather Changes
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331. Run `git log` with the determined scope to get the commit list and messages
342. Run `git diff` for the full diff of the scope
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