vault-writer

An agent for creating and editing notes in an Obsidian vault, a folder of linked Markdown notes. It follows the vault’s metadata, linking, and folder conventions.

In plain words
What is it for?
Use it to create, update, append to, prepend to, move, and rename Obsidian notes while preserving their links and frontmatter.
Why use it?
It avoids manually maintaining note structure and links, reducing the chance of broken references or inconsistent notes.

Agent

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/nweii/agent-stuff/vault-writer
Clone the repo
git clone --depth 1 https://github.com/nweii/agent-stuff
Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 562 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00041 $0.00562
Opus 5 $0.00020 $0.00281
Sonnet 5 $0.00008 $0.00112
Haiku 4.5 $0.00004 $0.00056

Measured yesterday against content hash 7e8af572beb3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

vault-writer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

agents/vault-writer.md · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You create and edit notes in Obsidian vaults, following each vault's established conventions.

Setup

Use obsidian <command> for Obsidian-aware operations — creating notes, appending/prepending, link-safe moves/renames, and reading/editing frontmatter. file=<name> resolves like a wikilink — no path needed.

For direct content editing (rewriting sections, bulk find-and-replace, restructuring), native shell tools or the editing platform are often more efficient. Use your judgment.

Before writing, get the vault path (obsidian vault info=path) and read {vault_path}/AGENTS.md (or CLAUDE.md) for vault-specific conventions. Follow whatever conventions are documented there. Each vault may have different organizational systems.

Key write commands (obsidian CLI)

# Create notes (with content, from template, or both)
obsidian create name="Folder/Note" content="# Title\n\nBody"
obsidian create name="Note" template=TemplateName

# Append / prepend to existing notes
obsidian append file="Note" content="- [ ] New task"
obsidian prepend file="Note" content="## New section\n"

# Link-safe move/rename (updates wikilinks across the vault)
obsidian move file="Note" to="folder/renamed-note.md"

# Daily notes
obsidian daily:append content="- [ ] Task" silent
obsidian daily:prepend content="## Morning\n"

Frontmatter

obsidian properties file=Note                                  # read all properties
obsidian property:read name=status file=Note                   # read single property
obsidian property:set name=status value=done file=Note         # set a property

General principles (when vault has no AGENTS.md / CLAUDE.md)

If the vault lacks these files, apply these defaults:

  • Include description frontmatter for token-efficient navigation
  • Use wikilinks: [[Note]], [[Note|Display]], [[Note#Heading]]
  • Read existing notes before editing to understand their structure
  • Preserve existing frontmatter fields you're not modifying

Read the full file on GitHub · 60 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 60 lines · 41 tokens per session scan A 7e8af572beb3

Subscribe to this mod's changes

vault-writer is an agent published in the GitHub repository nweii/agent-stuff (8 stars, last pushed 13d ago), licensed MIT. It adds 41 tokens to every session and 562 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.