Obsidian Writer

Role

Knowledge-base writer for the shared atmosphere-vault Obsidian vault. Applies Atmosphere frontmatter standards and directory conventions so every note lands in the right place with the right metadata — consistent enough to be searched, linked, and understood later.

When to Use

Invoke for any of these document types, whether the user names the type or not:

• ADR — Architecture Decision Record (Architecture/ADRs/)
• Runbook — Operational procedure or on-call guide (Development/Runbooks/)
• Plan — Feature or project planning document (Claude Plans/)
• API doc — Endpoint reference, SDK documentation (APIs/)
• Guide / how-to — Developer setup, walkthrough, tutorial (Development/)
• Session output — Claude Code session artifact (Claude Outputs/)
• Methodology — Process, workflow, team practice (Methodology/)

Workflow

Step 1 — Identify doc type and target directory

Use the quick-reference table below. When ambiguous, ask the user which type fits best.

Step 2 — Search for existing notes

Before creating, check whether a relevant note already exists to avoid duplicates:

obsidian search query="<keywords from the topic>" limit=5

If a match is found, read it first (obsidian read file="<name>") and decide whether to update the existing note or create a new one.

Step 3 — Compose content

Read references/vault-structure.md for the complete frontmatter field table.

Start every note with YAML frontmatter, then a level-1 heading matching the filename:

---
date: YYYY-MM-DD
tags: [atmosphere, <type-tag>]
status: <value>        # only for ADR and Plan
service: <name>        # only for Runbook and API doc
severity: <P0–P3>      # only for Runbook
---

# Note Title

Use [[wikilinks]] to link related vault notes — never absolute file paths.

Step 4 — Write to the live vault

Obsidian must be running and the atmosphere-vault must be the focused vault.

# Create a new note
obsidian create name="<Note Title>" path="<Directory/Filename.md>"

# Append a section to an existing note
obsidian append file="<Note Title>" content="## New Section\n<content>"

Step 5 — Verify and link

After writing, read the note back to confirm content landed correctly:

obsidian read file="<Note Title>"

Then update any related notes with a [[wikilink]] to the new document.

Quick Reference

Frontmatter Standards

ADR — required: date, status, tags: [atmosphere, adr]

• Status values: proposed → accepted → deprecated / superseded
• Filename convention: ADR-NNN Short Title.md (zero-padded number)

Runbook — required: date, severity, service, tags: [atmosphere, runbook, sre]

• Severity values: P0 (critical), P1 (high), P2 (medium), P3 (low)

Plan — required: date, status, tags: [atmosphere, plan]

• Status values: draft, active, completed

API doc — required: date, service, tags: [atmosphere, api]

Session output — required: date, tags: [atmosphere, claude-output]

Guide / how-to — required: date, tags: [atmosphere, guide, <domain>]

• Replace <domain> with the relevant area (e.g., runtime, spring, quarkus)

Key obsidian-cli Patterns

# Search before creating to avoid duplicates
obsidian search query="WebSocket backpressure" limit=5

# Read an existing note before editing
obsidian read file="ADR-042 Adopt Virtual Threads"

# Create a new note (Obsidian must be open and vault focused)
obsidian create name="ADR-042 Adopt Virtual Threads" \
  path="Architecture/ADRs/ADR-042 Adopt Virtual Threads.md"

# Append a section to an existing note
obsidian append file="ADR-042 Adopt Virtual Threads" \
  content="## Update 2026-03-14\nApproved in team review."

Constraints

• Obsidian must be running and the atmosphere-vault must be the active vault before using obsidian create or obsidian append — the CLI communicates with the open app.
• The obsidian command MUST be the first-party app CLI (/Applications/Obsidian.app/Contents/MacOS/obsidian). It needs no API key. If obsidian errors with "An API key must be provided via OBSIDIAN_API_KEY", a stray global npm package (obsidian-cli, the unrelated ObsidianQA tool) is shadowing it on PATH — fix with npm uninstall -g obsidian-cli, do NOT fall back to claude_docs/. Verify resolution with command -v obsidian.
• Always search first to avoid duplicate notes on the same topic.
• Always use [[wikilinks]] for internal vault references, not relative or absolute paths.
• Frontmatter date must be ISO 8601 format (YYYY-MM-DD).
• ADR filenames must include the zero-padded number prefix so they sort chronologically.
• After writing Claude-generated content, commit explicitly rather than waiting for the obsidian-git auto-commit (auto-commit runs every 10 minutes, explicit commits are easier to attribute and revert).
• See references/vault-structure.md for the full directory map and field reference.