Smart Connections is a free, open-source 📝Obsidian plugin that adds semantic search to a vault using an embedding model that runs entirely on the user's device.
Created by Brian Petro and first released in 2023, the plugin indexes a vault into vector embeddings locally, then surfaces notes by meaning rather than keyword match. It ships a built-in embedding model that requires no API key and no configuration, and can also be pointed at models served through Ollama. Two surfaces use the index: a Connections view that suggests related notes while writing, and a lookup that answers a natural-language question against the vault. Nothing leaves the machine unless the user deliberately configures a hosted model.
Key Facts
- Category: Obsidian community plugin for semantic search and note linking
- Created: 2023, by Brian Petro; free and open source
- Embeddings: On-device, zero setup, no API key; alternatives available via Ollama
- Indexing speed: Roughly 2.5 minutes for a 10,000-note vault on Apple Silicon
- Query latency: Under 100 milliseconds
- Agent access: Exposed to MCP clients through the third-party
smart-connections-mcpserver
How It Works
Local indexing. The plugin embeds note content on the device and maintains the index as the vault changes. Because the model ships with the plugin, a new user gets working semantic search without an account, a key, or a hosted service.
Connections view. While a note is open, the plugin surfaces semantically related notes and excerpts alongside it — a link-building aid that runs continuously rather than on demand.
Lookup. A natural-language query returns the passages that match by meaning, which is what finds a note whose wording the user has forgotten.
MCP bridge. A separate community project, smart-connections-mcp, exposes the existing index to MCP clients, giving an agent block-level semantic retrieval across one or more vaults without the vault contents being sent anywhere.
Why It Matters
Smart Connections is the reason "Obsidian has no semantic search" stopped being a true statement. The capability that once distinguished hosted knowledge platforms — retrieval by meaning rather than keyword — now installs in a click, runs offline, and costs nothing.
What it does not change is where that retrieval lives. The index sits on one device, tied to one vault, with no notion of who is allowed to see which note. Reaching it from a phone or a cloud agent means running the MCP bridge on a machine the user maintains, and an agent connected to it sees whatever the vault contains. The plugin closed a capability gap; the architectural gaps around permission and reach are untouched by it.
FAQ
Does Smart Connections send my notes to a cloud service?
No. The default embedding model runs on the device, and the index stays local. Hosted models are opt-in.
Does it need an API key?
No. It ships with a built-in local embedding model and works immediately after install.
How large a vault can it handle?
It indexes roughly 10,000 notes in about two and a half minutes on Apple Silicon and returns queries in under 100 milliseconds.
Can Claude use Smart Connections?
Yes, through the third-party smart-connections-mcp server, which exposes the plugin's index to MCP clients at block level.
Related
- 📝Obsidian — the application the plugin extends
- 📝Obsidian MCP — the server ecosystem the MCP bridge belongs to
- 📝MCP vs RAG — the retrieval-strategy distinction this plugin sits inside