Writing & notes
second-brain
Drop sources in a folder, get a cross-linked wiki
★ 710
April 2026
Not stated
Writing & notes
What we checked ourselves
Not copied from the project's own blurb. These are things we opened and verified, with the date.
- 9 Sept 2026We checked that the link to the project still resolves.
- 14 Aug 2026We read the licence text itself (null). No unusual restrictions were stated.
- 2 Sept 2026We read the project's own documentation and found no sign that development has stopped.
Where this sits among the 52 tools we list in Writing & notes
- Requires terminal commands38 that do not →
- Requires an API key27 that do not →
- Sends your input to the provider11 that do not →
Counted from our own checks: every tool we list is examined against the same criteria.
What it does
An implementation of the LLM Wiki pattern: raw articles, papers, notes and transcripts go into a folder, the model compiles them into structured pages with cross-references and a maintained index, and you read the result in Obsidian. The model is the librarian; you stay the curator. Everything you drop in reaches your provider, the bill scales with the pile, and compiled pages drift from what the source actually claimed — the originals stay for exactly that reason. No licence file was found.
Summary based on the project's own description. The Japanese page has a fuller beginner guide: setup difficulty, what to prepare, and a step-by-step start.
Screenshots & visuals
Before you start
- Setup difficultySome setup needed
- Command lineRequired
- API keyRequired
- Sends data onlineYes
Judged automatically from the project's own metadata. Always confirm on the official page.
second-brain FAQ
- Is second-brain free?
- second-brain itself is free, but it needs an API key for an external AI service. That service charges separately, though some have a free tier.
- Do I need to install anything or write code to use second-brain?
- It needs the command line. If you are not comfortable typing commands, expect to get stuck during setup.
- Does second-brain work on a phone?
- No. It needs a computer.
- Can I use second-brain commercially?
- We could not confirm this. The publisher does not state it clearly, so we have not verified whether what you make with it may be used commercially. Ask the publisher before relying on it.
How it compares
The conditions that decide whether you can actually use it, side by side.
| Tool | Command line | API key | Sends data out | Phone | Commercial use |
|---|---|---|---|---|---|
| second-brain (this page) | Required | Required | Yes | No | Not verified |
| Obsidian Copilot | Not needed | Required | Yes | No | Yes |
| obsidian-smart-connections | Not needed | Not needed | No | No | Not verified |
| obsidian-agent-client | Not needed | Required | Yes | No | Yes |
"Sends data out" means your input is uploaded to someone's server. Pick "No" when the material cannot leave your organisation.