Growth Log Skill

The problem: Most people write "fixed a bug in X" as a learning log. That's a diary entry, not a learning artifact. A real growth log extracts the pattern so you recognize it next time.

This skill teaches: How to write learning entries that compound across sessions. Works with any note-taking system — Markdown files, Notion, Obsidian, plain text. Templates are generic; adapt to your setup.

When to Activate

• After completing a complex task (multi-file, new feature, architecture change)
• After a failure, mistake, or "that was harder than expected" moment
• When you want to review what you've learned over a period

When NOT to activate: Trivial changes (typo fixes, single-line tweaks, config value changes with no debugging). The threshold: did this task involve debugging, redoing, rollback, or a non-obvious decision? If yes → write an entry. If no → skip.

The Three Rules

Rule 1: Failures > Achievements

A failure is nutritionally denser than a success. One bug that took 2 hours to find teaches more than 3 features that worked first try.

Bad: "Successfully implemented the login flow." Good (web dev): "Login flow: session token wasn't persisting because the cookie SameSite defaulted to Lax in Chrome 128+. Pattern: always explicitly set SameSite=None; Secure when cross-origin. Signal to recognize: auth breaks after browser upgrade or when crossing origin boundaries." Good (data pipeline): "CSV import failed silently on empty rows because pandas.read_csv(dropna=False) keeps zero-width rows that len() counts as valid. Pattern: always df.dropna(how='all', inplace=True) before row-count validation."

Rule 2: The Bole Principle (伯乐原则)

Before writing a new entry, ask: "Is this fundamentally the same as something I already recorded?"

Same root cause, different symptom → merge, don't duplicate. New root cause → new entry.

How to check: Search existing entries for keywords from your root cause before writing. If you find a match, add your new symptom as an additional example under the existing entry rather than creating a duplicate.

Example: "Forgot to update the output index after creating a file" and "Forgot to update skill ratings after a task" — same root cause (no automatic capture trigger). Merge into one entry about "post-task capture gaps."

Rule 3: Must Be Transferable

Every entry must answer: "Next time I face a similar situation, what do I do differently?"

If you can't write that sentence, you haven't extracted the pattern yet.

How to extract a pattern from a concrete event:

1. State what happened in one sentence
2. Ask "why?" iteratively until you reach root cause (usually 3-5 whys)
3. Generalize: "What class of problem is this?" (not "Chrome 128 bug" but "browser default change breaking existing behavior")
4. Formulate as: "Next time I see [signal], I will [action]."
5. Name the signal: what specific observable tells you this pattern is active?

Entry Template

Scope: One entry per distinct root cause. Typical length: 4-8 sentences. If it takes >2 minutes to write, you're narrating events. If <30 seconds, you haven't gone deep enough.

## [Title: the pattern, not the event]

### Context
- What was I trying to do?
- What went wrong / what worked surprisingly well?

### Root Cause / Core Insight
- The underlying mechanism, not just the symptom

### The Pattern (transferable)
- Next time [similar situation], I will [specific action].
- Signal to recognize: [what observable tells me this pattern is active?]

### Related
- [entry-name](../path/to/related-entry.md)

Entry Types

All four types use the template above. The type determines which sections carry the most weight:

Quality Checklist

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