ObsidianRAG

Ask questions about your Obsidian notes with a local-first hybrid RAG index.

ObsidianRAG 4 uses SQLite FTS5 and embedded LanceDB as its only retrieval engine. The Obsidian plugin manages the backend, index lifecycle, chat, and source links. Generation supports Ollama, LM Studio, and OpenAI-compatible servers.

Highlights

• Incremental copy-on-write index revisions
• Hybrid lexical and vector retrieval
• Grounded answers with numeric source citations
• Explicit Build, Refresh, Full rebuild, and Prune controls
• Reader leases that protect in-flight queries during refreshes
• Safe regular-Markdown scanning without following links
• API 4 compatibility checks between plugin and backend
• No shell invocation when the plugin starts the backend

Install

Install the backend:

uv tool install obsidianrag==4.0.1

Install the plugin assets from the plugin-v4.0.1 GitHub release:

• main.js
• manifest.json
• styles.css

Place them in <vault>/.obsidian/plugins/vault-rag/, then enable Vault RAG in Obsidian.

First run

1. Start your generation provider and make the configured model available.
2. Open Vault RAG settings and confirm the backend executable, usually obsidianrag (obsidianrag.exe on Windows).
3. Start the backend.
4. Select Build index.
5. Open the chat view.

The backend never indexes automatically at startup.

CLI

# Start API 4
obsidianrag serve --vault /path/to/vault

# Build or incrementally refresh
obsidianrag index --vault /path/to/vault

# Rebuild after incompatible embedding or chunk settings
obsidianrag index --vault /path/to/vault --full-rebuild

# Inspect and clean revisions
obsidianrag status --vault /path/to/vault
obsidianrag prune --vault /path/to/vault

# Retrieve without generation
obsidianrag search "deployment rollback" --vault /path/to/vault
obsidianrag search "deployment rollback" --vault /path/to/vault --lexical-only

# Ask through the v4 hybrid pipeline
obsidianrag ask "How do I roll back a deployment?" --vault /path/to/vault

Providers

Provider	Flag	Default URL	API format
Ollama	--provider ollama	http://localhost:11434	Ollama
LM Studio	--provider lmstudio	http://localhost:1234/v1	Chat completions
Custom	--provider custom	configured by user	Ollama or chat completions

Examples:

obsidianrag serve --vault /path/to/vault --provider ollama --model gemma3

obsidianrag serve --vault /path/to/vault \
  --provider lmstudio --model local-model \
  --base-url http://localhost:1234/v1

API keys configured in the plugin are session-only and are passed through the backend process environment, not command arguments.

Index architecture

flowchart LR
    Plugin[Obsidian plugin] --> API[FastAPI v4]
    API --> Pipeline[Query pipeline]
    Pipeline --> FTS[SQLite FTS5]
    Pipeline --> Vector[LanceDB]
    Pipeline --> LLM[Configured generation provider]
    Vault[Markdown vault] --> Builder[Copy-on-write index builder]
    Builder --> FTS
    Builder --> Vector

Revisions live under:

.obsidianrag/v4/
├── active.json
├── build.lock
├── indexes/<revision>/
└── leases/<revision>/

A refresh scans regular Markdown files, hashes note content, reuses unchanged vectors in bounded batches, and embeds only changed notes. A candidate revision activates only after SQLite, FTS5, deterministic IDs, paths, vector dimensions, and finite vector values validate successfully.

Readers lease their current revision. A new revision may activate while old requests finish; inactive leased revisions cannot be pruned.

API 4

Endpoint	Purpose
GET /capabilities	Exact plugin/backend protocol contract
GET /health	Process liveness and query readiness
GET /models	Models exposed by the configured provider
POST /ask	Complete grounded answer
POST /ask/stream	SSE answer stream
GET /index/status	Missing/current/stale/rebuild-required state
POST /index/build	Incremental build or explicit full rebuild
POST /index/prune	Remove unleased inactive revisions

API 3 clients and backends are intentionally incompatible with 4.0.1.

Migration from 3.x

• Install backend and plugin 4.0.1 together.
• Existing .obsidianrag/v4 revisions are reused when compatible.
• Legacy .obsidianrag/db Chroma data is ignored and never deleted automatically.
• Replace compound backend commands such as uv run obsidianrag with an executable path or name.
• Build the v4 index explicitly if no compatible revision exists.
• Remove legacy index data manually only after validating 4.0.1.

Development

git clone https://github.com/Vasallo94/ObsidianRAG.git
cd ObsidianRAG

cd backend
uv sync --locked --dev
uv run pytest
uv run ruff check .
uv run mypy .

cd ../plugin
pnpm install --frozen-lockfile
pnpm test
pnpm run lint
pnpm run build

Tests use temporary fixture vaults. Integration tests requiring a real provider are excluded from normal CI.

Release

Backend and plugin share version 4.0.1 but publish independently:

1. Tag backend-v4.0.1 and verify PyPI.
2. Tag plugin-v4.0.1 and verify GitHub release assets.

License

MIT. See LICENSE.