feat: V2.5 new skills P0 batch 1 (3 syntax skills)

New skills with full content:
- frappe-syntax-doctypes: 35+ fieldtypes, naming rules, child tables,
  tree, virtual, Custom Fields API, Property Setters
- frappe-syntax-reports: Query Report, Script Report, Number Cards,
  Dashboard Charts, Prepared Reports
- frappe-syntax-hooks-events: all doc_events in exact execution order,
  transaction behavior, extend_doctype_class [v16+]

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: FreekHeijting

skills/source/syntax/frappe-syntax-doctypes/SKILL.md

@@ -14,16 +14,278 @@ metadata:
 
 # DocType JSON Design
 
-> **STATUS**: Stub - content pending V2.5 development phase.
+DocTypes are the foundation of every Frappe application. A DocType defines both the **data model** (database schema) and the **view** (form layout). ALWAYS design DocTypes before writing any controller logic.
 
 ## Quick Reference
 
-_Content to be developed._
+### DocType JSON Top-Level Properties
 
-## Decision Tree
+| Property | Type | Purpose |
+|----------|------|---------|
+| `name` | str | DocType identifier (singular, e.g. "Sales Invoice") |
+| `module` | str | App module this DocType belongs to |
+| `is_submittable` | bool | Enables Draft -> Submitted -> Cancelled workflow |
+| `is_tree` | bool | Enables NestedSet hierarchy (lft/rgt columns) |
+| `is_virtual` | bool | No database table; data from custom backend |
+| `issingle` | bool | Single-instance settings document |
+| `istable` | bool | Child table DocType (embedded in parent) |
+| `is_calendar_and_gantt` | bool | Enables calendar/gantt views |
+| `track_changes` | bool | Stores version history on every save |
+| `track_seen` | bool | Tracks which users viewed the document |
+| `track_views` | bool | Counts total document views |
+| `allow_rename` | bool | Permits renaming after creation |
+| `allow_copy` | bool | Enables "Duplicate" action |
+| `allow_import` | bool | Enables Data Import for this DocType |
+| `naming_rule` | str | Naming method selector (see Naming section) |
+| `autoname` | str | Naming pattern string |
+| `title_field` | str | Field used as display title |
+| `search_fields` | str | Comma-separated fields for search results |
+| `show_title_field_in_link` | bool | Display title instead of name in Link fields |
+| `image_field` | str | Field containing image for avatar display |
+| `sort_field` | str | Default sort column |
+| `sort_order` | str | "ASC" or "DESC" |
+| `default_print_format` | str | Print Format name |
+| `max_attachments` | int | Attachment limit |
 
-_Content to be developed._
+### Common Fieldtypes (Quick Lookup)
+
+| Fieldtype | Stores | DB Column |
+|-----------|--------|-----------|
+| Data | Text up to 140 chars | VARCHAR(140) |
+| Link | Reference to another DocType | VARCHAR(140) |
+| Dynamic Link | Reference to any DocType | VARCHAR(140) |
+| Select | Single choice from options | VARCHAR(140) |
+| Table | Child table rows | Separate table |
+| Table MultiSelect | Multi-select link rows | Separate table |
+| Check | Boolean 0/1 | TINYINT |
+| Int | Whole number | INT |
+| Float | Decimal (9 places) | DECIMAL |
+| Currency | Money value (6 decimals) | DECIMAL |
+| Date | Calendar date | DATE |
+| Datetime | Date + time | DATETIME |
+| Text Editor | Rich text (HTML) | LONGTEXT |
+| Attach | File reference | VARCHAR(140) |
+| Small Text | Short multi-line text | TEXT |
+| Long Text | Unlimited text | LONGTEXT |
+
+> Full fieldtype reference with all 35+ types: [references/fieldtypes.md](references/fieldtypes.md)
+
+### Essential Field Properties
+
+| Property | Type | Purpose |
+|----------|------|---------|
+| `reqd` | bool | Field is mandatory |
+| `unique` | bool | Database UNIQUE constraint |
+| `search_index` | bool | Database INDEX for faster queries |
+| `in_list_view` | bool | Show in list view columns |
+| `in_standard_filter` | bool | Show as filter in list view |
+| `in_preview` | bool | Show in document preview |
+| `allow_on_submit` | bool | Editable after submission |
+| `read_only` | bool | Not editable by user |
+| `hidden` | bool | Not visible on form |
+| `depends_on` | str | Visibility condition (e.g. `eval:doc.status=="Active"`) |
+| `mandatory_depends_on` | str | Conditional mandatory |
+| `read_only_depends_on` | str | Conditional read-only |
+| `fetch_from` | str | Auto-populate from linked doc (e.g. `customer.customer_name`) |
+| `fetch_if_empty` | bool | Only fetch when field is empty |
+| `options` | str | Fieldtype-specific (DocType name, select options, etc.) |
+| `default` | str | Default value (supports `__user`, `Today`, etc.) |
+| `description` | str | Help text below field |
+| `collapsible` | bool | Section starts collapsed (Section Break only) |
+
+## Decision Tree: Which DocType Type?
+
+```
+Need to store data?
+├─ YES: Need multiple records?
+│  ├─ YES: Need submit/cancel workflow?
+│  │  ├─ YES → Standard DocType + is_submittable=1
+│  │  └─ NO: Need hierarchy/tree?
+│  │     ├─ YES → Tree DocType (is_tree=1)
+│  │     └─ NO: Embedded in parent?
+│  │        ├─ YES → Child DocType (istable=1)
+│  │        └─ NO → Standard DocType
+│  └─ NO: Single config/settings → Single DocType (issingle=1)
+└─ NO: Data from external source → Virtual DocType (is_virtual=1)
+```
+
+## Naming Rules
+
+ALWAYS set `naming_rule` on the DocType. The `autoname` field holds the pattern.
+
+| naming_rule Value | autoname Pattern | Example Output |
+|-------------------|------------------|----------------|
+| Set by User | _(empty)_ | User types name manually |
+| Autoincrement | _(empty)_ | `1`, `2`, `3` |
+| By Fieldname | `field:{fieldname}` | Value of that field |
+| By Naming Series | `naming_series:` | `INV-2024-00001` (from series field) |
+| Expression | `PRE-.#####` | `PRE-00001`, `PRE-00002` |
+| Expression (Old Style) | `{prefix}-{YYYY}-{#####}` | `INV-2024-00001` |
+| Random | `hash` | Random 10-char string |
+| UUID | _(empty)_ | `550e8400-e29b-...` |
+| By Script | _(custom)_ | Controller `autoname()` decides |
+
+> NEVER use Autoincrement in production -- gaps appear when records are deleted. Use Expression or Naming Series instead.
+
+> Full naming reference: [references/naming.md](references/naming.md)
+
+## Child Table Design
+
+A Child DocType is a DocType with `istable=1`. It ALWAYS belongs to a parent.
+
+**Parent side** -- add a field with:
+- `fieldtype`: `Table` (or `Table MultiSelect`)
+- `options`: Child DocType name
+
+**Child records automatically get**:
+- `parent` -- name of the parent document
+- `parenttype` -- DocType of the parent
+- `parentfield` -- fieldname of the Table field in parent
+- `idx` -- row order (1-based)
+
+```python
+# Adding child rows programmatically
+doc = frappe.get_doc("Sales Invoice", "INV-001")
+doc.append("items", {
+    "item_code": "ITEM-001",
+    "qty": 5,
+    "rate": 100.0
+})
+doc.save()
+```
+
+> NEVER create a Child DocType without `istable=1`. NEVER reference a non-child DocType in a Table field.
+
+### Table vs Table MultiSelect
+
+| Aspect | Table | Table MultiSelect |
+|--------|-------|-------------------|
+| UI | Full editable grid with "Add Row" | Tag-style picker, no "Add Row" |
+| Child DocType | Full child with many fields | Typically 1 Link field only |
+| Use case | Line items, detail rows | Multi-select references |
+
+## Single DocType (Settings Pattern)
+
+Set `issingle=1`. Data is stored in `tabSingles` as key-value pairs, NOT in a dedicated table.
+
+```python
+# Access Single DocType
+settings = frappe.get_single("My Settings")
+value = settings.some_field
+
+# Or directly
+value = frappe.db.get_single_value("My Settings", "some_field")
+```
+
+- NEVER expect a list view for Single DocTypes -- they have exactly one instance.
+- ALWAYS use for app-wide configuration (API keys, default values, feature toggles).
+
+## Tree DocType (NestedSet)
+
+Set `is_tree=1`. Frappe adds `lft`, `rgt`, `parent_{doctype_fieldname}`, `old_parent` columns automatically.
+
+- ALWAYS define a `parent_field` in the DocType JSON (e.g. `parent_account` for Chart of Accounts).
+- The NestedSet model uses `lft`/`rgt` integers for efficient subtree queries.
+- NEVER manually edit `lft`/`rgt` values. Use `frappe.utils.nestedset.rebuild_tree()` if corrupted.
+
+```python
+# Get all descendants
+descendants = frappe.get_all("Account",
+    filters={"lft": [">", node.lft], "rgt": ["<", node.rgt]})
+
+# Get ancestors (path to root)
+ancestors = frappe.get_all("Account",
+    filters={"lft": ["<", node.lft], "rgt": [">", node.rgt]},
+    order_by="lft asc")
+```
+
+## Virtual DocType
+
+Set `is_virtual=1`. No database table is created. ALWAYS implement these controller methods:
+
+```python
+class MyVirtualDoc(Document):
+    def db_insert(self, *args, **kwargs):
+        # Persist to your custom backend
+        pass
+
+    def load_from_db(self):
+        # Load document data from your source
+        pass
+
+    def db_update(self, *args, **kwargs):
+        # Update in your custom backend
+        pass
+
+    def delete(self):
+        # Remove from your custom backend
+        pass
+
+    @staticmethod
+    def get_list(args):
+        # Return list of documents
+        pass
+
+    @staticmethod
+    def get_count(args):
+        # Return total count
+        pass
+
+    @staticmethod
+    def get_stats(args):
+        # Return statistics
+        pass
+```
+
+> NEVER use `frappe.db.*` calls for Virtual DocType data -- they only work with the site database, not your custom backend.
+
+## Customization APIs
+
+### Custom Fields (Programmatic)
+
+```python
+from frappe.custom.doctype.custom_field.custom_field import create_custom_fields
+
+# Dict format: {DocType: [field_dicts]}
+create_custom_fields({
+    "Sales Invoice": [
+        dict(fieldname="custom_tracking", label="Tracking ID",
+             fieldtype="Data", insert_after="naming_series")
+    ],
+    "Purchase Order": [
+        dict(fieldname="custom_vendor_ref", label="Vendor Ref",
+             fieldtype="Data", insert_after="supplier")
+    ]
+}, update=True)
+```
+
+### Property Setter (Programmatic)
+
+```python
+from frappe.custom.doctype.property_setter.property_setter import make_property_setter
+
+# Change a field property on an existing DocType
+make_property_setter("Sales Invoice", "customer", "reqd", 1, "Check")
+make_property_setter("Sales Invoice", "posting_date", "default", "Today", "Text")
+```
+
+> Full customization reference: [references/customization.md](references/customization.md)
+
+## Critical Rules
+
+1. ALWAYS name DocTypes in **singular** form ("Sales Invoice", not "Sales Invoices").
+2. ALWAYS use the `tab` prefix mentally -- the DB table is `tabSales Invoice`.
+3. NEVER exceed 140 characters for Data/Link/Select field values.
+4. ALWAYS set `search_index=1` on fields used in frequent filters or `get_list` calls.
+5. ALWAYS set `in_standard_filter=1` on fields users frequently filter by.
+6. NEVER use `allow_on_submit=1` on child table fields that affect calculations without recalculating totals.
+7. ALWAYS set `fetch_if_empty=1` alongside `fetch_from` unless you want to overwrite user edits.
+8. NEVER define `depends_on` with raw Python -- use `eval:doc.fieldname == "value"` syntax.
 
 ## See Also
 
-_Cross-references to be added._
+- [references/fieldtypes.md](references/fieldtypes.md) -- Complete fieldtype reference
+- [references/naming.md](references/naming.md) -- All naming methods with examples
+- [references/examples.md](references/examples.md) -- Real DocType JSON examples
+- [references/anti-patterns.md](references/anti-patterns.md) -- Common schema design mistakes
+- [references/customization.md](references/customization.md) -- Custom Fields and Property Setter APIs