Second Brain Ingest

Ingest a source

An ingest that only writes a summary page produces a vault that grows without getting smarter. The whole value is in the second half of the job: connecting the new material to what is already there. A page that lands unlinked is invisible within a week.

Core rule

Nothing is ingested until it is linked. Every run ends with the new pages connected to existing pages in both directions.

Workflow

1. Read the source completely before writing anything. Partial reads

produce pages built from the introduction, which is where sources are least specific.

1. Check what already exists. Search the wiki for the main entities and

concepts. Ingesting into an empty vault and ingesting into a vault of 300 pages are different jobs: in the second, most of your work is updating pages, not creating them.

1. Write the source page in wiki/sources/. Record claims as claims, with

the source attached.

1. Extract concepts and entities. One page per idea. If a concept page

exists, add what this source contributes and update updated:. If it contradicts what is there, record both positions rather than replacing.

1. Link in both directions. The source page links to every concept and

entity it touches; each of those links back. Add any missing target pages, or list them under Gaps in index.md.

1. Update index.md and append to log.md in the same run, because an

index that lags is how a vault starts drifting.

1. Report what changed.

Output format

End every run with this exact shape:

Ingested: 
New pages:  (list)
Updated pages:  (list)
Links added: 
Contradictions found: 
Gaps created: 

Calibration

Over-extraction is the common failure: ten thin concept pages from one article, each a restated paragraph. A source usually yields one to three concepts worth their own page. If a candidate concept cannot be explained without referring back to this one source, it belongs inside the source page instead.

Under-extraction shows up as source pages that contain three separate ideas and link to nothing. If a page needs section headings for unrelated topics, split it.

Example

Input: the user drops raw/karpathy-llm-wiki.md, a clipped gist, into a vault that already has pages for [[Obsidian]] and [[Claude Code]].

Output: one source page; a new concept page [[LLM wiki]] explaining the pattern in plain language; an entity page [[Andrej Karpathy]]; updates to [[Obsidian]] and [[Claude Code]] noting their role in the pattern; a link from the existing [[Personal knowledge management]] concept to the new one; index and log updated; report showing 3 new, 3 updated, 11 links.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: undefined-ui
• Source: undefined-ui/second-brain-os
• License: MIT
• Homepage: https://x.com/undefinedKi/status/2068306794116501544

Install and usage instructions live in the source repository linked above.