obsidian-bases

What this skill does

# Obsidian Bases Skill

This skill enables Claude Code to create and edit valid Obsidian Bases (`.base` files) including views, filters, formulas, and all related configurations.

## Overview

Obsidian Bases are YAML-based files that define dynamic views of notes in an Obsidian vault. A Base file can contain multiple views, global filters, formulas, property configurations, and custom summaries.

## File Format

Base files use the `.base` extension and contain valid YAML. They can also be embedded in Markdown code blocks.

## Complete Schema

```yaml
# Global filters apply to ALL views in the base
filters:
  # Can be a single filter string
  # OR a recursive filter object with and/or/not
  and: []
  or: []
  not: []

# Define formula properties that can be used across all views
formulas:
  formula_name: 'expression'

# Configure display names and settings for properties
properties:
  property_name:
    displayName: "Display Name"
  formula.formula_name:
    displayName: "Formula Display Name"
  file.ext:
    displayName: "Extension"

# Define custom summary formulas
summaries:
  custom_summary_name: 'values.mean().round(3)'

# Define one or more views
views:
  - type: table | cards | list | map
    name: "View Name"
    limit: 10                    # Optional: limit results
    groupBy:                     # Optional: group results
      property: property_name
      direction: ASC | DESC
    filters:                     # View-specific filters
      and: []
    order:                       # Properties to display in order
      - file.name
      - property_name
      - formula.formula_name
    summaries:                   # Map properties to summary formulas
      property_name: Average
```

## Filter Syntax

Filters narrow down results. They can be applied globally or per-view.

### Filter Structure

```yaml
# Single filter
filters: 'status == "done"'

# AND - all conditions must be true
filters:
  and:
    - 'status == "done"'
    - 'priority > 3'

# OR - any condition can be true
filters:
  or:
    - 'file.hasTag("book")'
    - 'file.hasTag("article")'

# NOT - exclude matching items
filters:
  not:
    - 'file.hasTag("archived")'

# Nested filters
filters:
  or:
    - file.hasTag("tag")
    - and:
        - file.hasTag("book")
        - file.hasLink("Textbook")
    - not:
        - file.hasTag("book")
        - file.inFolder("Required Reading")
```

### Filter Operators

| Operator | Description |
|----------|-------------|
| `==` | equals |
| `!=` | not equal |
| `>` | greater than |
| `<` | less than |
| `>=` | greater than or equal |
| `<=` | less than or equal |
| `&&` | logical and |
| `\|\|` | logical or |
| `!` | logical not |

## Properties

### Three Types of Properties

1. **Note properties** - From frontmatter: `note.author` or just `author`
2. **File properties** - File metadata: `file.name`, `file.mtime`, etc.
3. **Formula properties** - Computed values: `formula.my_formula`

### File Properties Reference

| Property | Type | Description |
|----------|------|-------------|
| `file.name` | String | File name |
| `file.basename` | String | File name without extension |
| `file.path` | String | Full path to file |
| `file.folder` | String | Parent folder path |
| `file.ext` | String | File extension |
| `file.size` | Number | File size in bytes |
| `file.ctime` | Date | Created time |
| `file.mtime` | Date | Modified time |
| `file.tags` | List | All tags in file |
| `file.links` | List | Internal links in file |
| `file.backlinks` | List | Files linking to this file |
| `file.embeds` | List | Embeds in the note |
| `file.properties` | Object | All frontmatter properties |

### The `this` Keyword

- In main content area: refers to the base file itself
- When embedded: refers to the embedding file
- In sidebar: refers to the active file in main content

## Formula Syntax

Formulas compute values from properties. Defined in the `formulas` section.

```yaml
formulas:
  # Simple arithmetic
  total: "price * quantity"
  
  # Conditional logic
  status_icon: 'if(done, "✅", "⏳")'
  
  # String formatting
  formatted_price: 'if(price, price.toFixed(2) + " dollars")'
  
  # Date formatting
  created: 'file.ctime.format("YYYY-MM-DD")'
  
  # Complex expressions
  days_old: '((now() - file.ctime) / 86400000).round(0)'
```

## Functions Reference

### Global Functions

| Function | Signature | Description |
|----------|-----------|-------------|
| `date()` | `date(string): date` | Parse string to date. Format: `YYYY-MM-DD HH:mm:ss` |
| `duration()` | `duration(string): duration` | Parse duration string |
| `now()` | `now(): date` | Current date and time |
| `today()` | `today(): date` | Current date (time = 00:00:00) |
| `if()` | `if(condition, trueResult, falseResult?)` | Conditional |
| `min()` | `min(n1, n2, ...): number` | Smallest number |
| `max()` | `max(n1, n2, ...): number` | Largest number |
| `number()` | `number(any): number` | Convert to number |
| `link()` | `link(path, display?): Link` | Create a link |
| `list()` | `list(element): List` | Wrap in list if not already |
| `file()` | `file(path): file` | Get file object |
| `image()` | `image(path): image` | Create image for rendering |
| `icon()` | `icon(name): icon` | Lucide icon by name |
| `html()` | `html(string): html` | Render as HTML |
| `escapeHTML()` | `escapeHTML(string): string` | Escape HTML characters |

### Any Type Functions

| Function | Signature | Description |
|----------|-----------|-------------|
| `isTruthy()` | `any.isTruthy(): boolean` | Coerce to boolean |
| `isType()` | `any.isType(type): boolean` | Check type |
| `toString()` | `any.toString(): string` | Convert to string |

### Date Functions & Fields

**Fields:** `date.year`, `date.month`, `date.day`, `date.hour`, `date.minute`, `date.second`, `date.millisecond`

| Function | Signature | Description |
|----------|-----------|-------------|
| `date()` | `date.date(): date` | Remove time portion |
| `format()` | `date.format(string): string` | Format with Moment.js pattern |
| `time()` | `date.time(): string` | Get time as string |
| `relative()` | `date.relative(): string` | Human-readable relative time |
| `isEmpty()` | `date.isEmpty(): boolean` | Always false for dates |

### Date Arithmetic

```yaml
# Duration units: y/year/years, M/month/months, d/day/days, 
#                 w/week/weeks, h/hour/hours, m/minute/minutes, s/second/seconds

# Add/subtract durations
"date + \"1M\""           # Add 1 month
"date - \"2h\""           # Subtract 2 hours
"now() + \"1 day\""       # Tomorrow
"today() + \"7d\""        # A week from today

# Subtract dates for millisecond difference
"now() - file.ctime"

# Complex duration arithmetic
"now() + (duration('1d') * 2)"
```

### String Functions

**Field:** `string.length`

| Function | Signature | Description |
|----------|-----------|-------------|
| `contains()` | `string.contains(value): boolean` | Check substring |
| `containsAll()` | `string.containsAll(...values): boolean` | All substrings present |
| `containsAny()` | `string.containsAny(...values): boolean` | Any substring present |
| `startsWith()` | `string.startsWith(query): boolean` | Starts with query |
| `endsWith()` | `string.endsWith(query): boolean` | Ends with query |
| `isEmpty()` | `string.isEmpty(): boolean` | Empty or not present |
| `lower()` | `string.lower(): string` | To lowercase |
| `title()` | `string.title(): string` | To Title Case |
| `trim()` | `string.trim(): string` | Remove whitespace |
| `replace()` | `string.replace(pattern, replacement): string` | Replace pattern |
| `repeat()` | `string.repeat(count): string` | Repeat string |
| `reverse()` | `string.reverse(): string` | Reverse string |
| `slice()` | `string.slice(start, end?): string` | Substring |
| `split()` | `string.split(separator, n?): list` | Split to list |

### Number Functions

| Function | Signature | Description |
|----------|-----------|-------------|
| `abs()` | `number.abs(): number` | Absolute value |
| `cei