# Obsidian Bases

> ALWAYS invoke when working with Obsidian Bases (.base files), database views, filters, formulas, or the Bases query language. Triggers: .base file, Bases view, filter formula, vault database.

- **Type:** Skill
- **Install:** `agentstack add skill-doctormozg-claude-pipelines-obsidian-bases`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [DoctorMozg](https://agentstack.voostack.com/s/doctormozg)
- **Installs:** 0
- **Category:** [Databases](https://agentstack.voostack.com/c/databases)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [DoctorMozg](https://github.com/DoctorMozg)
- **Source:** https://github.com/DoctorMozg/claude-pipelines/tree/master/plugins/mz-knowledge/skills/obsidian-bases

## Install

```sh
agentstack add skill-doctormozg-claude-pipelines-obsidian-bases
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Obsidian Bases

## Overview

Obsidian Bases is a native database/spreadsheet feature introduced in Obsidian 1.x. A `.base` file is a YAML document that defines filtered, formula-enriched, grouped views over vault notes. This skill provides authoritative Bases syntax — filters, formulas, property namespaces, view types, and summaries — so edits to `.base` files produce valid, working queries.

## When to Use

Invoke when the user mentions `.base` files, Bases views, filter formulas, vault-level databases, or asks to build a query that lists/groups/summarizes notes across the vault.

### When NOT to use

- Dataview queries (DQL, `TABLE`, `LIST`, `WHERE` syntax, or JavaScript views) — different query language, not Bases.
- Standard frontmatter edits on a single note — no Bases file involved.
- Obsidian plugin development or community plugin config — Bases is a core feature, not a plugin.

## Core Process

1. **Read vault CLAUDE.md** (if present) for custom property naming conventions before writing any formula. Property names in formulas must match the vault's frontmatter keys exactly.
1. **Determine filter criteria** — which notes the view should include. Translate the user's intent into `file.hasTag`, `file.inFolder`, frontmatter property comparisons, or compound `and`/`or`/`not` blocks.
1. **Define properties, formulas, and view type** — pick `table`, `cards`, `list`, or `map`; list the columns/fields; add formulas for any computed values.
1. **Watch for Duration pitfalls** — subtracting two dates returns a `Duration`, not a `Number`. Always chain `.days` / `.hours` / `.minutes` before feeding into numeric functions or display.

## Techniques

**File structure.** A `.base` file is valid YAML with these optional top-level keys: `filters`, `formulas`, `properties`, `summaries`, `views`.

**Filters.**

```yaml
filters: "file.hasTag('project')"

filters:
  and:
    - "file.hasTag('project')"
    - "file.inFolder('02 - Areas')"

filters:
  not: "file.hasTag('archived')"
```

Filter functions: `file.hasTag(tag)`, `file.hasLink(note)`, `file.inFolder(path)`, `.matches(regex)`. Logical operators inside strings: `&&`, `||`, `!`.

**Property namespaces.**

- Note frontmatter: `propertyName` (direct, unqualified).
- File metadata: `file.name`, `file.basename`, `file.path`, `file.folder`, `file.ext`, `file.size`, `file.ctime`, `file.mtime`, `file.tags`, `file.links`, `file.backlinks`, `file.embeds`, `file.properties`.
- Computed: `formula.formulaName`.
- `this` resolves to the current note in main content, the embed host inside an embed, and the sidebar target when viewed in the sidebar.

**Formulas.**

```yaml
formulas:
  age: "date.now() - file.ctime"
  daysSinceModified: "(date.now() - file.mtime).days"
```

Duration pitfall: `date.now() - file.mtime` returns a `Duration`. Access `.days`, `.hours`, `.minutes`, etc., before passing to numeric functions, rounding, or comparisons against numbers.

**Views.**

```yaml
views:
  - type: table
    name: "All Notes"
    properties: [file.name, status, file.mtime]
    sort: [{property: file.mtime, direction: desc}]
    groupBy: status
```

View types: `table`, `cards`, `list`, `map`.

**Summaries.**

```yaml
summaries:
  status:
    formula: count
```

Built-in summary formulas: `Average`, `Min`, `Max`, `Sum`, `Range`, `Median`, `Stddev`, `Earliest`, `Latest`, `Checked`, `Unchecked`, `Empty`, `Filled`, `Unique`, `Count`.

**Embedding.**

- `![[MyBase.base]]` embeds the full base.
- `![[MyBase.base#View Name]]` embeds a specific named view.

**YAML quoting.** When a formula string contains double quotes, wrap the string in single quotes:

```yaml
formulas:
  label: 'if(status == "done", "done", "open")'
```

Reference: grep `references/functions-reference.md` for formula function signatures by return type (Date, Duration, String, Number, Boolean, List, File). Do not load the full file — grep for the function name or category you need.

## Common Rationalizations

N/A — reference skill, not discipline.

## Red Flags

- Using `(date.now() - file.mtime)` directly as a number — must access `.days` / `.hours` / etc. Duration is not a Number.
- Using DQL keywords (`TABLE`, `FROM`, `WHERE`, `SORT`) — that is Dataview, not Bases. Bases uses YAML with filter functions.
- Wrapping a formula string in double quotes when the formula itself contains double quotes — YAML parse error. Use single quotes around the outer string.
- Using `tag:` (singular frontmatter-style) inside a filter expression instead of `file.hasTag()` — filter context needs the function call form.
- Referencing a frontmatter property with the `file.` prefix (e.g., `file.status`) — frontmatter properties are unqualified. `file.` is reserved for file metadata.

## Verification

To confirm the skill was applied correctly, output a sample `.base` snippet that lists all notes with tag `project`, sorted by `file.mtime` descending, showing name and status columns. The snippet should parse as valid YAML and use only the namespaces and functions documented above.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [DoctorMozg](https://github.com/DoctorMozg)
- **Source:** [DoctorMozg/claude-pipelines](https://github.com/DoctorMozg/claude-pipelines)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-doctormozg-claude-pipelines-obsidian-bases
- Seller: https://agentstack.voostack.com/s/doctormozg
- Browse the marketplace: https://agentstack.voostack.com/browse

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