Skill: brain-sync

Trigger: Call after every single file migration (Odoo) OR after any general Python/JS/Bash/Shell bug fix. Never batch multiple files into one sync.

Step 1 — Classify the fix FIRST

Before writing anywhere, assign ONE type:

Rule: Could this mistake happen in ANY Odoo module? → Framework type → global files Could this ONLY make sense reading THIS module's code? → [Module-Specific] → ledger only

Step 2 — Route by type

Framework types ([API-Change] / [Field-Change] / [XML-Change] / [Security-Change] / [Performance-Tip]):

→ Odoo-Mistakes.md          (one-line global rule)
→ Mistakes/[MODULE]_ledger.md   (compact project reference)
→ Notes/[TYPE]_Notes.md         (full intern explanation)
   API-Change     → API_Notes.md
   Field-Change   → Field_Notes.md
   XML-Change     → XML_Notes.md
   Security-Change → Security_Notes.md
   Performance-Tip → Performance_Notes.md

[Module-Specific]:

→ Mistakes/[MODULE]_ledger.md ONLY
   Do NOT write to Odoo-Mistakes.md or any Notes file

Step 3 — Write formats

Odoo-Mistakes.md (global rules — one entry per fix)

### [XML-Change] <tree> renamed to <list>
- **Avoid:** `<tree string="...">` in any view file
- **Always:** Use `<list string="...">` in Odoo 19
- **Why:** Odoo renamed the tag to match what it actually is
- **First seen in:** estate

[MODULE]_ledger.md (project handoff — next subagent reads this)

## [views/estate_property_views.xml] — Fix: <tree>→<list>
- **Type:** [XML-Change]
- **Before:** `<tree string="Properties">`
- **After:** `<list string="Properties">`
- **Impact on other files:** None
- **Notes ref:** [[XML_Notes#tree-renamed-list]]

[TYPE]_Notes.md (intern study guide — full explanation, always this format)

## 🔖 [XML-Change] — <tree> renamed to <list>
**First seen in:** estate | **Ledger ref:** [[estate_ledger#tree-list]]

### 🧠 WHY Odoo 19 changed this
[Explain the architectural/design reason. Write to someone in their first month
of Odoo. Not "it changed" — WHY the Odoo team decided to change it.]

### 📅 WHEN you will see this as an intern
[Real situations where they'll encounter this. Which modules, which workflows.]

### 🏗️ Real Scenario
[Actual before/after code from the file just migrated — not a generic example]

```python or xml
# ❌ Odoo 17
[old code]

# ✅ Odoo 19
[new code]

⚠️ Common Mistakes Interns Make

1. [Specific mistake with this change]
2. [Another specific mistake]
3. [Edge case they'd miss]

---

## Step 4 — Confirm after every sync

✅ brain-sync complete File: models/estate_property.py Type: [API-Change] Odoo-Mistakes.md: updated estate_ledger.md: updated API_Notes.md: new section "@api.ondelete replaces unlink()"

---

## General Coding Mistakes (non-Odoo)

If the fix is a **general Python / JavaScript / Bash / Shell** mistake (not Odoo-specific):

**Route to:** `<VAULT_ROOT>/Development/General-Mistakes.md`

**Format:**
```markdown
### [CATEGORY] — Short description
- **Avoid:** what not to do
- **Always:** what to do instead
- **Why:** the reason
- **First seen in:** [project name]

Categories: [Python], [JavaScript], [Bash], [Git], [SQL], [Claude-CLI], [General]

Confirm after sync:

✅ brain-sync complete
   Type: General / [CATEGORY]
   General-Mistakes.md: updated

What brain-sync NEVER does

• Never writes [Module-Specific] fixes to global Odoo-Mistakes.md
• Never batches multiple files into one sync call
• Never writes to any file inside the Git repo / module directory
• Never skips the Why/When/Then — even for "obvious" fixes